Huda Y. Zoghbi - US grants

Spinocerebellar ataxia is a progressive neurodegenerative disorder with autosomal dominant inheritance. The first symptoms may occur in the second or third decade where the patient may have already started a family. Presently there is no accurate method of presymptomatic or prenatal diagnosis of this severely disabliting disease. The biology and structure of the ataxia genes are totally unknown at this time. One form of spinocerebellar ataxia is known to be linked to the HLA genes on chromosome 6. We propose to use family studies in order to map the gene for the HLA-linked spinocerebellar ataxia with greater accuracy and to subsequently clone that gene. This project can be achieved through the use of the most recent advances in recombinant DNA technology. The specific aims are (1) to establish detailed linkage map on each side of the ataxia gene relying on the use of DNA restriction fragment length polymorphisms; (2) to narrow down the DNA region by analysis of crossovers; (3) to obtain an overlapping set of DNA clones which will bridge between the flanking markers by using gene walking techniques; and 4) to identify the spinocerebellar ataxia gene utilizing Southern transfer techniques, analysis of genomic clones and studies of RNA expression.

The overall goal of this project is to clone and characterize the gene for the HLA-linked form of autosomal dominant spinocerebellar ataxia (SCA1). SCA1 is a neurodegenerative disorder with onset of symptoms in the mid-adulthood. The disease is progressive and results in death 10-15 years after onset. Studies from our laboratory using multilocus linkage analysis and somatic cell lybridiazation techniques have mapped the SCA1 gene locus centromeric to the HLA loci. Detailed linkage and deletion mapping of the relevant region of chromosome 6p is in progress. The first phase in this proposal is to isolate additional DNA clones that are more closely linked to SCA using a genomic DNA library that will be prepared from a hybrid cell line retaining 6p as the only human chromosome. In addition a more enriched source for markers close to SCA1 will be generated by isolating hybrid clones retaining fragments of chromosome 6p. Once the SCA1 gene region is saturated with polymorphic DNA markers, chromosomal hopping and walking techniques as well as analysis of recombinants will be used to narrow the region to 1-2 million base pairs (mb). the second phase will involve physical mapping of the SCA1 region and the identification of transcribed sequences in that region. Pulsed field gel electrophoresis will be performed and cosmid clones within the 1-2 mb surrounding the SCA1 locus will be used to establish a set of overlapping contiguous DNA segments. DNA sequences employing a variety of approaches including the identification of HpaII tiny fragments (HTF) islands, examination for evolutionary sequence conservation, and Northern blotting analysis. Alternative strategies to clone the SCA1 gene will be pursued using cerebellar cDNA clones that map to the relevant region on chromosome 6p. The last phase of the proposal will be to prove whether a candidate sequence represents the SCA! genomic sequence or gene product. This will be achieved using a variety of novel and standard studies including comparative Southern blot analysis using DNA fractionated by conventional and pulsed field gel electrophoresis, Northern blotting analysis, ribonuclease cleavage studies and sequencing of the wild type and mutant SCA1 cDNAs. If the SCA1 gene is identified efforts will focus on characterizing the structure and biological function of the SCA1 gene to elucidate the mechanism of pathogenesis in this disease.

Aicardi and Goltz syndromes are both X-linked dominant disorders with lethality in males. We have collected cell lines from a number of patients with chromosomal rearrangements showing clinical features of Aicardi syndrome, Goltz syndrome, or both. These patents suffer from a combination of clinical features and developmental defects which include agenesis of the corpus callosum, seizures, developmental delay, retinal lesions, microphthalmia and skin defects. The phenotypes of these patients show significant overlap, suggesting that the same gene, or two or more contiguous genes, may be involved. The variability of the phenotype may be due to the effects of X-inactivation. In all these cases the chromosomal rearrangement results in a terminal deletion involving the Xp22.2-Xp22.3 region, strongly suggesting that the loci for Aicardi and Goltz syndromes map to this region. Therefore: these cell lines represent ideal tools to perform positional cloning of the genes which are mutated in Aicardi and Goltz syndromes. Somatic cell hybrids from these cell lines will be established in order to separate the abnormal X chromosome from the normal one. Precise mapping of the Aicardi and Goltz syndrome critical regions will be obtained by testing the hybrid cell lines with numerous existing and newly generated markers from Xp22.2Xp22.3. We will then perform overlap cloning using yeast artificial chromosome (YAC) clones obtained from several libraries, including a library specifically made from a hybrid retaining the human Xp2l-pter region. YAC subclones will be used for the identification of genes from the region. The expression pattern and sequence analysis of the genes will be examined in normal individuals and in patients affected by Aicardi and Goltz syndromes to determine their involvement in the pathogenesis of these diseases. Further studies will include the characterization of the structure and function of the disease genes and of their products.

Spinocerebellar ataxia type 1 (SCA1) is an autosomal dominant neurodegenerative disorder characterized by progressive ataxia, motor impairment, and bulbar dysfunction. Neuropathological findings include loss of cerebellar Purkinje cells, degeneration of spinocerebellar tracts, and neuronal loss in various cranial nerve nuclei. The disease causes death 10-20 years after onset of symptoms because of respiratory failure. We have identified the SCA1 gene and determined that the disease causing mutation is an expansion of a translated CAG repeat which encodes glutamine. We characterized the SCA1 gene product, ataxin-1, in both normal and disease states using transgenic mice and patient tissues. Through the study of animal models, we demonstrated that mutant ataxin-1 causes SCA1 by a gain function mechanism. We also show that mutant ataxin-1 localizes to a 2 mum nuclear structure in brain tissue from SCA1 patients and transgenic mice. Mutant ataxin-1 alters the distribution of the promyelocytic oncogenic domain in the nucleus and interacts with the cerebellar leucine rich acidic nuclear protein (LANP). Based on these data we propose that SCA1 pathogenesis involves the disruption of key nuclear functions and that the selective neuronal degeneration is mediated by the interaction of ataxin-1 with LANP. The overall goal of this proposal is to test these main hypotheses and to investigate the mechanism of pathogenesis in SCA1. To accomplish this goal we will use genetic, biochemical, and cell biological approaches. To begin with, we will characterize a new mouse model for SCA1 generated by inserting an expanded polyglutamine tract into the endogenous mouse Sca1 gene. This animal model will express mutant ataxin-1 in all the neurons typically affected in SCA1. We will generate and characterize mouse models that either lack or over-express LANP to elucidate the normal function of LANP and its role in SCA1 pathogenesis. We will also identify proteins that interact with LANP using the yeast two-hybrid system to identify the potential pathways and/or cellular functions affected by the interaction of mutant ataxin-1 with LANP. We will carry out detailed characterization of the nuclear structures formed by mutant ataxin-1 to gain insight into their role in the pathogenesis and to identify potential mechanisms by which they disrupt neuronal function. Lastly, we will identify new proteins that are down-stream effectors of the SCA1 mutation by carrying out subtractive cloning using transgenic SCA1 mice and wild-type litter- mates. These studies should enhance our understanding of the pathogenic mechanism in SCA1 and other neurodegenerative disorders caused by polyglutamine expansion.

This is a competing renewal of a multidisciplinary research program project for the study of the clinical, molecular genetic, physiologic and pathologic aspects of Rett syndrome (RS). Over the past 10 years the research activities of this Center resulted in the definition of the unique clinical phenotype of RS, suggested the neurodevelopmental nature of RS, and broadened our hypotheses regarding genetic models. A large cohort of patients has been characterized and enrolled in the various research protocols which led us to classify RS as a developmental disorder. This assessment is a departure from the initial interpretation of RS as being a progressive, degenerative disease and led to the genesis of the following hypotheses which will be addressed in this renewal application: (1) RS is either X-linked or autosomal dominant with sex limited expression. (2) RS is the result of a selective arrest of brain development. (3) The developmental arrest in RS results from a deficiency of the neurotropic activity of neurotransmitters, particularly monoamine and GABAergic neurotransmitters. (4) The arrest of brain development in RS is associated with impaired maturation and growth of the whole body, as well as specific systems such as the cardiac conduction system. Project 5 will investigate candidate genes on the X-chromosome for mutations; complete genetic mapping studies in familial cases; use representational difference analysis to identify new mutations in the genomic DNA of RS; and characterize sexually-dimorphic genes expressed in the CNS. Project 6 will study the features in brain and heart which suggest developmental arrest using morphology, immunocytochemistry and quantitation of neurotransmitter receptor binding densities. Project 8 will characterize the morphology, maturation, and chemoarchitecture of the nervous system deprived of the trophic effects of monoamines, with emphasis on developing a neuropathologic model of RS. Project 7 will assess somatic growth failure in RS by evaluating the mechanisms by which the partitioning of protein and calcium balance is altered using stable isotope techniques. These projects are served by the Core which is the Center for patient identification, education, follow-up, and research protocol enrollment. The Core integrates research activities, provides statistical design and analysis support, and continues to develop an already extensive data base that is not only used regularly for patient identification and selection, but also for the generation of hypotheses. The Baylor College of Medicine Rett Center brings together a multidisciplinary team to study in an integrated fashion the many dimensions of this enigmatic disorder.

The X-linked neurodevelopmental disorder Rett syndrome (RTT) is one of the leading causes of mental retardation (MR) and autism in females. 80% of girls with RTT have mutations in the gene encoding methyl-CpG- binding protein 2 (MeCP2), a transcriptional repressor that binds methylated cytosines. The phenotypic consequences of MECP2 mutations range from classic RTT in those with random X chromosome inactivation (XCI) to mild or even no MR in girls with favorable XCI. We hypothesize that impaired MeCP2 function leads to misexpression of genes crucial for neuronal development, which mediates RTT pathogenesis and some forms of autism and MR. Project 1 (Dr. Zoghbi) will create mouse models for RTT for pathogenesis and therapeutic studies, use microarray technology to evaluate alterations in gene expression in the RTT mice, and genotypic sporadic females and female relatives of RTT girls with MR, autism, or learning disabilities. Project 2 (Drs. Glaze and Percy) will clinically characterize the girls studied in Project 1 and test whether methyl donors (folate and betaine) can ameliorate neurologic dysfunction in RTT by enhancing cytosine methylation. Project 3 (Dr. Van den Veyver) will characterize expression of MECP2 variants in developing brain and in RTT tissue; correlate effects of MECP2 mutations on gene expression in human cell lines, mouse embryonic stem cells and Xenopus with expression data from mouse models (Project 1) and study changes in DNA methylation by methyl donors administered to mice in Projects 1 and 2. The Morphology-Neuropathology portion of the Core (Dr. Armstrong) will do systematic morphological analyses on mouse models (Project 1) and conduct immunohistochemical studies on mouse and human tissues (Project 3). Through these multi-disciplinary studies we hope to identify the cause of MR/LD or autism in a subset of patients, to gain insight into the pathogenesis of RTT, and to develop therapeutic strategies for this and related late-onset neurodevelopmental diseases.

[unreadable] DESCRIPTION (provided by applicant): This application for supplementary funding to the Baylor College of Medicine Mental Retardation Research Center seeks to establish a collaborative Fragile X Syndrome Research Center composed of investigators at Baylor College of Medicine in Houston, Texas and Emory University School of Medicine in Atlanta, Georgia. The application seeks funding for four investigator-initiated research projects and two core facilities. The four projects will revolve around a common theme of delineating the full spectrum of phenotypes and their underlying bases in humans and mice with genetic alterations in the FMR1 gene. This will include a series of investigations into the consequences of moderately expanded CGG repeats (premutations) that have been linked to premature ovarian failure and a late onset neurodegeneration. An Administrative Core will be proposed to facilitate interactions among the four research laboratories and the two institutions, and funding is sought to expand core services currently provided by the Baylor College of Medicine MRRC Mouse Neurobehavior and Synaptic Plasticity Core directed by Drs. Richard Paylor and David Sweatt. Additional funding will allow the core to expand services and to characterize the increased numbers of models anticipated to be created in the proposed Center. The four principal investigators proposing projects are Drs. David Nelson and Richard Paylor of Baylor College of Medicine, and Drs. Stephen Warren and Stephanie Sherman of Emory University. Each of these investigators has developed a strong track record of research into fragile X syndrome, and the group is now in a unique position to investigate this novel pathogenic component of fragile X syndrome. Dr. Sherman will investigate the epidemiology of the human male premutation phenotype that involves late onset tremor and cognitive decline. Dr. Nelson will develop mouse models to study effects of premutations and FMR1 gene overexpression. Dr. Warren will investigate proteins that bind selectively to expanded CGG and which may be important to premutation disease as well as fragile X syndrome, and Dr. Paylor will focus on improved methods for characterizing mouse models of fragile X syndrome and their response to treatment. [unreadable] [unreadable]

[unreadable] DESCRIPTION (provided by applicant): The Baylor College of Medicine (BCM) Mental Retardation and Developmental Disabilities Research Center (MRDDRC) was established on August 1, 1988 and has been continuously funded with the last renewal of funding on August 1, 1998. The overall goals of the Baylor MRDDRC are to identify as many causes of mental retardation and developmental disabilities as possible, to prevent these disorders, and to provide interventional schemes that can improve the quality of life of afflicted individuals and ameliorate their disability whenever possible. The specific objectives are: 1) to enhance mental retardation activities at BCM by encouraging and focusing research efforts on etiology, diagnosis, prevention, pathogenesis and intervention of MRDD; 2) to continue to promote a multidisciplinary approach to MRDD research by improving interactions between Center investigators, and by continuing to develop and to apply leading edge technologies; 3) to enhance the productivity of project investigators through effective and efficient research core units and to facilitate translational research efforts by providing clinical research support; 4) to recruit new investigators into the field of MRDD research through scientific interactions with Center investigators and by providing the infrastructure for a multidisciplinary approach through the MRDDRC cores; and 5) to promote scientific and collaborative interactions with investigators outside Baylor who have demonstrated a major commitment to study and treat MRDD. The research projects will be supported by the Administrative Core (A), and by seven research cores: Genome Analysis, which includes FISH and Genome-Based Arrays (B), Gene Expression which includes Neuropathology, Confocal, RNA in situ, and MicroArray Expression (C), Tissue Culture (D), Clinical Research (E), Mouse Genetic Engineering, which includes Mouse Embryonic Stem Cell and Mouse Microinjection (F), Mouse Neurobehavior (G), and Mouse Physiology (H). There are 53 faculty participants, including 46 research project investigators and 83 research projects. The scope of research at the BCM MRDDRC will include the following eleven topic areas: 1) neurobiology, cellular and molecular aspects of brain development, 2) inborn errors of metabolism, 3) genetic and epigenetic basis of diseases, 4) innovative technologies for diagnosis & screening MRDD, 5) animal models for pathogenesis & therapeutic intervention, 6) pathways that affect function of nervous system, 7) molecular, behavioral & therapeutic studies in MR syndrome, 8) clinical trials, 9) infectious diseases, 10) methods to define clinical phenotypes, and 11) studies of Autism & Autism Spectrum disorders. [unreadable] [unreadable]

[unreadable] DESCRIPTION (provided by applicant): The Baylor College of Medicine (BCM) Mental Retardation and Developmental Disabilities Research Center (MRDDRC) was established on August 1, 1988 and has been continuously funded with the last renewal of funding on August 1, 1998. The overall goals of the Baylor MRDDRC are to identify as many causes of mental retardation and developmental disabilities as possible, to prevent these disorders, and to provide interventional schemes that can improve the quality of life of afflicted individuals and ameliorate their disability whenever possible. The specific objectives are: 1) to enhance mental retardation activities at BCM by encouraging and focusing research efforts on etiology, diagnosis, prevention, pathogenesis and intervention of MRDD; 2) to continue to promote a multidisciplinary approach to MRDD research by improving interactions between Center investigators, and by continuing to develop and to apply leading edge technologies; 3) to enhance the productivity of project investigators through effective and efficient research core units and to facilitate translational research efforts by providing clinical research support; 4) to recruit new investigators into the field of MRDD research through scientific interactions with Center investigators and by providing the infrastructure for a multidisciplinary approach through the MRDDRC cores; and 5) to promote scientific and collaborative interactions with investigators outside Baylor who have demonstrated a major commitment to study and treat MRDD. The research projects will be supported by the Administrative Core (A), and by seven research cores: Genome Analysis, which includes FISH and Genome-Based Arrays (B), Gene Expression which includes Neuropathology, Confocal, RNA in situ, and MicroArray Expression (C), Tissue Culture (D), Clinical Research (E), Mouse Genetic Engineering, which includes Mouse Embryonic Stem Cell and Mouse Microinjection (F), Mouse Neurobehavior (G), and Mouse Physiology (H). There are 53 faculty participants, including 46 research project investigators and 83 research projects. The scope of research at the BCM MRDDRC will include the following eleven topic areas: 1) neurobiology, cellular and molecular aspects of brain development, 2) inborn errors of metabolism, 3) genetic and epigenetic basis of diseases, 4) innovative technologies for diagnosis & screening MRDD, 5) animal models for pathogenesis & therapeutic intervention, 6) pathways that affect function of nervous system, 7) molecular, behavioral & therapeutic studies in MR syndrome, 8) clinical trials, 9) infectious diseases, 10) methods to define clinical phenotypes, and 11) studies of Autism & Autism Spectrum disorders. [unreadable] [unreadable]

[unreadable] DESCRIPTION (provided by applicant): The fragile X syndrome (FXS), a type of inherited mental retardation, is due to the silencing of the FMR1 X-linked gene. In over 98% of cases, the mutation is due to the expansion of an unstable CGG repeat sequence located in the 5' untranslated region (UTR) of the gene. Once expanded to over 200 repeats, the FMR1 gene is hypermethylated and consequently no message is transcribed and no protein (FMRP) produced. Until recently, the unmethylated long CGG repeat track found in premutation carriers (60-200 repeats) was thought to have little phenotype consequence. The original goal of this study was to substantiate reports of an association between premutation male carriers and a late-onset neurodegenerative disorder resulting in action tremors - this has been accomplished through this project and others. This syndrome, now referred to as fragile X-associated tremor/ataxia syndrome (FXTAS), has a variable age at onset and progression. The principal investigator's focus now is to characterize the natural history of the syndrome and to identify risk factors associated with expression and severity. She will delineate the FMR1-related molecular correlates that best predict the risk for FXTAS among premutation males and females. Identification of such risk factors will provide clues for the underlying molecular etiology. In the last two years of the study, the investigator has gained significant experience with this syndrome and the issues related to recruiting participants. The investigator has an established infrastructure and study protocol to identify families with FXS, and to systematically ascertain all individuals in a sibship with a premutation carrier. The investigator's test battery to assess an individual's tremor/ataxia phenotype is unique, as she has instrumentation that objectively quantifies outcome measures. However, she has come upon several roadblocks that she did not anticipate with this study, and has requested a supplement to enhance the value of this study. First, the investigator requests funds to cover travel costs to expand her study population. She finds it necessary to travel to a participant's home to conduct the phenotype assessments due to their limitations. Second, imaging studies are essential to better characterize FXTAS and provide diagnostic criteria to the neurology community. Thirdly, the investigator is in great need of a genetic counselor to provide results and discuss FXTAS with family members. The older men in the families with FXS typically have not come to clinics with their grandsons who have FXS - they do not understand inheritance of this disorder and certainly had no idea that they may be at risk for a neurodegenerative disorder. Thus it is essential to have a genetic counselor associated with the study and one who will identify counseling issues specific to FXTAS and establish guidelines for others in this situation. With these additional funds, the results of this project will be immediately translatable to the medical community. [unreadable] [unreadable]

[unreadable] DESCRIPTION (provided by applicant): Rett syndrome [RTT, MIM 312750] is an X-linked postnatal developmental disorder characterized by loss of acquired skills, impairment of cognitive and motor functions, autonomic dysfunction, ataxia, tremors, seizures, autistic features, and stereotypic hand movements. RTT is caused by mutations in the X-linked MECP2 gene which encodes methyl-CpG-binding protein 2 (MeCP2). MeCP2 is thought to be a transcriptional repressor that links DNA methylation to chromatin modifications. Recently, we also found that MeCP2 interacts with an RNA-binding protein and can affect RNA splicing. We and others have shown that mutations in MECP2 cause a broad spectrum of disorders that display partial features of RTT such as autism, mild mental retardation, movement abnormalities, or seizures. Favorable X-chromosome-inactivation patterns in some of these patients and in partially symptomatic female mice that model RTT led us to propose that the diverse phenotypes of classic RTT result from MeCP2 dysfunction in a particular subset of neurons. Furthermore, we propose that loss of function of MeCP2 in specific neurons causes gene expression and RNA splicing changes that mediate the neuron-specific phenotypes. Lastly, we propose that pharmacologic therapies that target some of the neuron-specific changes linked to distinct phenotypes are likely to modulate some of these RTT phenotypes. The Specific Aims of this project are: (1) To identify the neuroanatomical bases of several key features of RTT by deleting Mecp2 in distinct neuronal populations -- using Cre/LoxP technology-- and characterizing the phenotypes of the conditional mutant mice. (2) To identify MeCP2 targets by evaluating neuron-specific gene expression and splicing pattern changes in Mecp 308/y mice which reproduce RTT phenotypes; we will use a novel approach that employs neuron- specific BACarray lines and new splicing/expression arrays. (3) To conduct preclinical pharmacologic trials targeted at clinically relevant molecular changes (based on Data from Aims 1 and 2) to determine if such therapies will alter the RTT disease course. As a proof of concept, we will use drugs that modulate CRH and AVP activities given our discovery of the potential roles of these two MeCP2 targets in RTT phenotypes. These studies will provide insight about the neuronal subtypes and neurotransmitter systems that mediate certain key features of RTT and related disorders such as autism and X-linked mental retardation. They will also provide the community with a rich resource of neuron-specific gene expression/splicing patterns and how some of these patterns differ in RTT. Last but not least, the data generated under this study have the potential to identify effective pharmacologic interventions that could benefit RTT patients. [unreadable] [unreadable] [unreadable]

The Administrative core supports the research projects in the BCM IDDRC by assuring appropriate access to quality research core services, and through ongoing assessment of excellence, in order to facilitate their research efforts. Periodic surveys of investigators have helped in re-designing the core services. These are also a primary means of assessment of core quality and efficacy. The interdisciplinary nature of the BCM IDDRC has stimulated new directions to research activities in intellectual and developmental disabilities at BCM. The Administrative core will continue to maintain an approach to a dynamic and developing center, and to foster creative research directions that will impact on the quality of life for individuals with intellectual disability.

DESCRIPTION (provided by applicant): This proposal is responsive to RFA-MH-09-170, the Recovery Act Limited Competition: Research to Address the Heterogeneity in Autism Spectrum Disorders (R01). As noted in the RFA, Autism spectrum disorders (ASD) form a very heterogeneous group: over 30 distinct genes have been identified as either causing or contributing to the cause of autism. To better understand how such a diverse array of genes can cause similar ASD phenotypes, we searched for the binding partners of proteins encoded by autism-associated genes and developed an autism protein interaction network (an "interactome") that contains over 900 protein interactions, many of which are novel. One of the most exciting discoveries unveiled by this interactome is the finding that there are three "hub" proteins that are centers for interaction: FXR1, SHANK3, and TSC1. Moreover, SHANK3 interacts with two distinct classes of proteins: one involved in synapse structure, the other involved in RNA metabolism and translation. This latter class connects SHANK3 to the Fragile X protein (FMRP) and its paralogs (FXR1 and 2) as well as the tuberous sclerosis complex proteins (TSC1 and TSC2). Based in part on these findings, we hypothesize that there are shared pathogenic mechanisms amongst various ASD, one of which centers on synapse maintenance and plasticity. We propose that SHANK3 plays two distinct roles at the synapse, one involving synapse organization and maintenance and the other involving local RNA translation at the synapse. To gain insight into key mechanisms underlying ASD pathogenesis, we will identify and characterize the native SHANK3 complexes at the synapse in vivo. To accomplish this, we will generate knock-in mice that tag the SHANK3 protein to permit in vivo purification of SHANK3-associated complexes. We will examine SHANK3 native complexes to determine whether there are distinct classes of SHANK3 protein complexes and the type of proteins in these sub-complexes. We will generate mice that either black or over-express Shank3 and we will characterize these Shank3 mouse models. In addition we will analyze behavioral, anatomical, and physiological consequences of modulating Shank3 expression in mice lacking FXR genes. Detailed behavioral and biochemical studies will allow us to establish a functional relationship between SHANK3 and FXR proteins in vivo and provide a foundation for detailed mechanistic studies that should benefit a broad population of ASD patients. PUBLIC HEALTH RELEVANCE: Autism is a heterogeneous disorder caused by mutations in different genes and is considered a major public health problem given the estimated prevalence of 1 in 150-200 children. We discovered that some autism- causing proteins interact with the same partners suggesting that there are shared pathways that lead to autism. In this grant, we will characterize some common pathways leading to autism, which would be of public health relevance because our studies will help many types of autism rather than one or two subtypes.

The Neuropathology Core is part of an integrated BCM-IDDRC core involved in defining the sites of gene expression, the sites of protein expression, and high-resolution cell biological changes. The key laboratory personnel in the past were Dr. Dawna Armstrong, Mrs. Barbara Antalffy and Ms. Shana Davis, all of whom remained through 2006. Dr Armstrong retired at the end of the academic year in 2006, whereupon the Directorship of the Core Lab was handed over to Dr. Meena Bhattacharjee, a pediatric neuropathologist who is interested in pursuing many aspects of pathological changes that accompany IDD. Ms. Shana Davis moved on in 2006, and Mrs. Barbara Antalffy retired in April 2008. However prior to her retirement, Mrs. Antalffy helped transition all the cores technical duties to Mrs. Deena Parghi, an experienced histotechnologist and research associate Mrs. Parghi who joined the laboratory in August 2006. There was a period of nearly two years over which time Mrs. Antalffy was able to train Mrs. Parghi in all aspects of the detailed work that is a hallmark of this core laboratory, and this insured a smooth transition in the work of the core laboratory. Dr. Yan Gao joined the Core in 2008, and will be a valuable asset for the Neuropathology core laboratory.

The Baylor College of Medicine (BCM) Intellectual and Developmental Disabilities Research Center (IDDRC) was established on August 1, 1988 and has been continuously funded with the last renewal of funding dated July 1, 2004. The specific objectives are: 1) To enhance intellectual disabilities activities at BCM by encouraging and focusing research efforts on etiology, diagnosis, prevention, pathogenesis, and intervention of IDD. 2) To continue to promote a multidisciplinary approach to IDD research by improving interactions among Center investigators, and by continuing to develop and to apply leading edge technologies. 3) To enhance the productivity of project investigators through effective and efficient research core units and to facilitate translational research efforts. 4) To recruit new investigators into the field of IDD research through scientific interactions with center investigators and by providing the infrastructure for a multidisciplinary approach through the BCM-IDDRC Cores. 5) To promote scientific and collaborative interactions with investigators outside Baylor who have demonstrated a major commitment to study and treat IDD. The research projects will be supported by the Administrative Core (A), and by seven research cores: High Throughput Genomic & RNA Analysis (B), Genome-Wide RNAi Analysis (C), Gene Expression Analysis which includes Neuropathology, Confocal, and RNA in situ (D), Tissue Culture (E), Stem Cell (F), Mouse Neurobehavior (G), and Mouse Physiology (H). There are 48 faculty participants, including 41 research project investigators and 73 research projects. The scope of research at the BCM-IDDRC will include the following ten topic areas: 1) Neurobiology, cellular & molecular aspects of brain development; 2) Inborn errors of metabolism; 3) Genetic & epigenetic basis of diseases; 4) Innovative technologies for diagnosis & screening IDD; 5) Animal models for pathogenesis & for developing and testing therapeutics; 6) Pathways that affect function of nervous system; 7) Molecular, behavioral & therapeutic studies in IDD including fragile X, Angelman, Prader-Willi, and Rett syndromes; 8) Definition of clinical phenotypes in genetically diagnosed populations; 9) Studies of aggression, social behavioral problems and stereotypies; and 10) Neurobiology, genetics, pathogenesis & pharmacological approaches in autism spectrum disorders.

DESCRIPTION (provided by applicant): The objective of this proposal is to build out 3 floors (total) in the Jan and Dan Duncan Neurological Research Institute (NRI) to accelerate research in understanding and treating disorders of the brain and mind. Baylor College of Medicine (BCM) and Texas Children's Hospital (TCH) investigators, through the support of six NIH institutes, HHMI, and several disease foundations, have been at the forefront of unraveling the molecular genetics of numerous neurological and neurodevelopmental disorders. The availability of excellent animal models for these disorders and the potential reversibility of several (demonstrated in mice) makes them ideally suited for an intense multidisciplinary effort to develop therapy. BCM and TCH conceived the NRI, a 350,000 sf silver-level LEED-certified research institute connecting BCM, TCH and MD Anderson, to be the first institute in the world devoted to childhood neurological disease. NRI will foster translational research in this class of diseases by 1) locating current BCM/TCH researchers working on these diseases under one roof, near TCH clinicians, 2) providing space to recruit needed expertise, and 3) establishing core services specifically conceived to support translational research in these diseases (e.g., neurophysiology, neuropathology, NMR/metabolomics, behavior, pharmacology/preclinical drug trials, mathematics/bioinformatics). TCH raised money for most of the first phase of this project, completed a 13-floor building shell, and will complete Floors 1 (admin, conference rooms), 3 (animal facility), 12, 13 and part of 11 by late 2010. This is insufficient, however, to allow NRI to begin functioning as it should. To accomplish that, we need to finish: Floor 11 (7025 sf) to recruit three new faculty;Floor 10 (22,705 sf) to relocate five BCM faculty performing neuropsychiatric disease-oriented research and recruit three new faculty;and Floor 2 (6125 sf): space for the NMR Metabolomic Core. As a result of this construction project, we estimate that 192 jobs directly assisting with construction will be maintained or created;recruiting new PIs over the next 3 years to the NIH-finished floors would create 100 jobs in the short-to-intermediate term. Based on previous data calculating the impact of the medical center on the Houston area economy, we estimate that every NRI employee will indirectly support three other jobs in the Houston region, and that every dollar invested in NRI generates $1.44 in local tax revenue. Ultimately, however, the discovery of treatments for these devastating diseases will restore quality of life and reduce their terrible economic burden on families and society.

STRATEGY I. OBJECTIVES OF THE ADMINISTRATIVE CORE The mission of the IDDRC is to enhance IDD research activities at BCM by supporting research on etiology, diagnosis, prevention, pathogenesis, and the development of therapies to treat IDD. Our objectives are to: 1. Support faculty research into IDD through strategic core facilities and develop new core services as fields advance. 2. Strengthen our multidisciplinary approach to IDD research by fostering interactions between Center investigators and recruiting investigators from other fields into the field of IDD research. 3. Facilitate scientific and collaborative interactions with investigators outside Baylor who have demonstrated a major commitment to study and treat IDD. The Administrative Core will continue to meet these objectives by wisely administering funds awarded to the IDDRC, maintaining a high-quality infrastructure to support the research projects, and spurring collaborations amongst investigators at BCM as well with investigators at other institutions. The Administrative Core will also actively seek additional funding for IDD research and will help new investigators find funding opportunities with the most appropriate agencies and foundations for their research projects.

? DESCRIPTION (provided by applicant): The Baylor College of Medicine Intellectual and Developmental Disabilities Research Center (BCM IDDRC) was established August 1, 1988, and has been continuously funded with the last renewal of funding July 1, 2009. The BCM IDDRC is committed to advancing research in intellectual and developmental disabilities (IDD) to address the problems encountered by individuals with IDD and their families. Specifically, the mission of the BCM IDDRC are to identify as many causes of intellectual and developmental disability as possible, to understand the mechanisms mediating these disorders, to prevent these disorders, and to provide interventions that can improve the quality of life of affected individuals and ameliorate their disability whenever possible. The specific objectives are: 1) To enhance IDD research activities at BCM by encouraging and focusing research efforts on etiology, diagnosis, prevention, mechanism of pathogenesis, and the development of therapies to treat IDD, 2) To develop and provide innovative and critical core facilities to enhance IDD research at BCM, 3) To promote a multidisciplinary approach to IDD research by improving interactions between Center investigators and recruiting new investigators into the field of IDD research, and 4) To promote scientific and collaborative interactions with investigators outside BCM who have demonstrated a major commitment to study and treat IDD. The BCM IDDRC is structured around the major themes of discovering the genetic and genomic basis of IDD, developing disease models of IDD, performing detailed pathogenesis studies of IDD, and developing novel therapies for IDD. The mission and goals of the BCM IDDRC will be accomplished by providing innovative, important, and cost-effective research core services to support high quality investigators and research projects aligned with the mission, goals, and objectives of the IDDRC. The BCM IDDRC proposes A) an Administrative Core, B) a Clinical Translational Core, C) a Rodent Neurobehavioral Core, D) a Neurovisualization Core which includes Neuropathology, Confocal, and RNA in situ, and (E) a Neuroconnectivity Core which includes Viral Production, Optogenetics, and In vivo Physiology. Additionally, the BCM IDDRC will support an innovative preclinical research project entitled Steps towards a paternal gene activation therapy for Angelman syndrome that will develop novel, genetically based treatments for that neurodevelopmental disorder. These core resources will support 45 investigators and 56 NIH funded research projects. Over the last 25 years the BCM IDDRC has been remarkably successful in fostering the discovery of the causes of IDD, determining the pathophysiology of IDD, and developing treatments for IDD. Ongoing funding will allow the Center to continue to support and expand these efforts at BCM.

? DESCRIPTION (provided by applicant): Spinocerebellar ataxia type 1 (SCA1) is a dominantly inherited, fatal neurodegenerative disease that is characterized by progressive motor incoordination and bulbar dysfunction, due primarily to destruction of cerebellar Purkinje cells (eventually the inferior olive and brain stem cranial nuclei are also compromised). Caused by expansion of a translated CAG repeat that encodes a polyglutamine tract in ATAXIN1 (ATXN1) and that alters ATXN1's interactions with its native protein partners, SCA1 shares several features with other more common neurodegenerative proteinopathies such as Parkinson and Alzheimer disease. Two are central to this grant: first, the disease-driving protein is prone to accumulate in neurons; second, there is differential vulnerability to disease pathology among different brain regions despite ubiquitous expression of the disease- driving protein. Over the past four years we have made significant progress investigating the molecular basis of both these features. We discovered that the elevation of steady-state levels of mutant ATXN1, not the aggregation per se, is toxic, and that the toxicity of mutant ATXN1 is primarily due to a gain of its normal functions, particularly those mediated by its native protein partner Capicua-at least in the cerebellum. We therefore explored whether reducing ATXN1 levels mitigates disease. We found that genetic reduction of Capicua (which in turn reduces the activity of both mutant and wild-type ATXN1) mitigates the cerebellar phenotype of SCA1 knock-in mice, as does reduction of 14-3-3e (one of ATXN1's stabilizing binding partners). Our recent unbiased, cross-species, forward genetic screen also revealed that partial inhibition of the RAS- MAPK-MSK1 pathway rescues the cerebellar phenotype. Unfortunately, neither Capicua, 14-3-3, nor ATXN1 itself are viable therapeutic targets at present-but the RAS-MAPK-MSK1 pathway provides a number of druggable targets and, indeed, there are already several drugs used in human patients that inhibit this pathway. In this grant, we propose to evaluate the efficacy and safety of pharmacological inhibitors of the RAS- MAPK-MSK1 pathway (Aim I), as well as screen for additional modifiers that reduce ATXN1 levels in both human cells and our SCA1 Drosophila model (Aim II). Given that SCA1 is a chronic disease, it is likely that combination therapy that mildly inhibits two to three distinct pathways controlling ATXN1 levels will be much safer and better tolerated by patients. We will also investigate region-specific modifications and interactions of ATXN1 to identify those critical for ATXN1 toxicity, using our newly generated mice carrying tagged knock-in Atxn1 alleles for the wild-type and mutant proteins (Aim III). This is not only to find pathways that may mitigate extra-cerebellar symptoms, but to gain further biological insight into ATXN1 functions in both SCA1 pathogenesis and development. The proposed studies stand to identify viable potential therapeutic entry points for SCA1 and provide a strategy and insights relevant to other neurodegenerative proteinopathies.

PROJECT SUMMARY/ABSTRACT: The Eunice Kennedy Shriver Intellectual and Developmental Disabilities Research Center at Baylor College of Medicine (BCM IDDRC) has been instrumental in advancing basic science, translational, and clinical endeavors to improve the lives of individuals with intellectual and developmental disability (IDD). Beyond discoveries, the Center has mentored more than two generations of scientists and physicians engaged in research and the care and treatment of individuals with IDD. The mission of the BCM IDDRC is to identify as many causes of IDD as possible, to understand their pathogenesis, and to develop novel diagnostic and therapeutic approaches. To realize this mission, accelerate the research activities of our Investigators and advance development of therapeutics for IDD, we will carry out the following aims: 1) Provide Core facilities and services to advance IDD research. Six cores are proposed to provide innovative, high-quality and cost-effective research services to assist investigators in studies of molecules (Molecular and Expression Analysis), cells and tissues (Cell and Tissue Pathogenesis), circuits (Circuit Analysis and Modulation), and whole organisms (Preclinical and Clinical Outcomes). The Clinical Translational Core will provide services specific for clinical research infrastructure and the Center Administration Core will coordinate overall Center operations along with stakeholder engagement, communication and education; 2) Promote and enhance collaborative efforts and dissemination activities with a comprehensive engagement, communication, and education plan. The Admin Core will promote interactions locally, nationally, and internationally, will implement best practices for community partnerships and dissemination of research findings, and will enhance the training of next-generation IDD researchers; 3) Conduct a multidisciplinary signature research project that leads to clinical trial readiness. The emergence of DNA-based therapies, coupled with exciting discoveries and preclinical studies from the BCM IDDRC, provides exciting opportunities to treat IDDs, but the fact that many IDD-causing genes are dosage sensitive (too much or too little is detrimental) poses a serious challenge requiring robust biological markers meaningful for the individual rather than the population. The Signature Project seeks to develop multidimensional biomarkers (molecules and circuits) for target engagement, safety, and efficacy in six gene dosage dependent IDDs. The Center will support 75 investigators and 72 research projects. For 30+ years the BCM IDDRC has had a profound impact on IDD, elucidating causes, determining mechanisms, and developing interventions. It has fostered an environment that welcomes and supports additional investigators and emphasizes training. As we enter the next decade, Center investigators, their collaborators, and trainees are poised to transform dozens of exciting discoveries into safe therapeutics that will improve the quality of life and well-being of individuals with IDD.