1991 — 1993 |
Hu, James W |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Brain Stem Mechanisms of Deep Craniofacial Pain
The long-term objectives of our research program are to clarify the central mechanisms underlying acute and chronic craniofacial pain and its control. Our recent NIH-supported research has resulted in major new insights into the neuroplasticity of the trigeminal (V) brainstem complex, and into brainstem mechanisms underlying deep (e.g. muscle; and temporomandibular joint, TMJ) as well as cutaneous (facial) pain. These latter studies, carried out in subnucleus caudalis since it has been particularly implicated in orofacial pain mechanisms, have suggested mechanisms that may be involved in signaling pain and in its spread and referral and that may be manifested in pathophysiological situations such as temporomandibular/myofascial pain dysfunction and inflammation. To clarify these mechanisms further, we will first address hypotheses that A: Caudalis neurons receiving deep as well as cutaneous nociceptive afferent inputs project directly to the posterior thalamus and/or parabrachial area, PBA; B: Application of an inflammatory irritant to masticatory muscle( masseter and tongue muscles) or temporomandibular (TM) region enhances the peripherally evoked responses to cutaneous or deep stimuli of caudalis nociceptive neurons; block of C-fiber afferents markedly diminishes this enhancement; and C: Descending modulatory influences from the periaqueductal gray (PAG) and rostroventral medulla (RVM) can depress the peripherally evoked responses to deep as well as cutaneous stimuli of caudalis nociceptive neurons; local anesthesia or lesioning of RVM can diminish the depressive effects of PAG stimulation. Electrophysiological recordings will be made from functionally identified brainstem nociceptive and nonnociceptive neurons in subnucleus caudalis of rats to determine if neurons receiving deep nociceptive afferent inputs project to regions implicated in more central processing of pain and if these neurons' activity can be modulated by TM and muscle afferents excited by irritant substances and by central modulatory influences implicated in the control of pain. Since neural alterations associated with injury and inflammation may be involved in several craniofacial pain conditions including temporomandibular/ myofascial pain dysfunction, the information gained from this research will provide a better understanding of acute and chronic craniofacial pains and their control.
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0.958 |
1993 — 2005 |
Hu, James |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Genetic Dissection of the Specificity of Leucine Zipper Dimerization @ Texas a&M Research Foundation
The proposed studies apply classical phage genetic approaches to the screening of massive combinatorial primary structure libraries related to the leucine zipper of yeast transcription factor GCN4. The object of these studies is to define sequences which can form heterodimers with wild type GCN4 leucine zippers, and to characterize primary sequence requirements for heterodimerization. %%% The roles of amino acid side chains in protein dimerization processes will be evaluated by altering the primary sequence randomly of a simple leucine zipper structural motif. The functional significance of each new structure (there will be millions of such structures) will be screened, in a genetics based system, in terms of ability to dimerize. Two types of populations will be sequenced: (1) those molecules which can form heterodimers with the wild-type GCN4 leucine zipper, and (2) those molecules which form stable homodimers, but not heterodimers (with the wild- type leucine zipper). Such studies will shed considerable insight into the structural constraints involved in peptide-peptide, protein-protein interactions.
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0.904 |
1996 — 1998 |
Hu, James W |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Brain Stem Mechanisms of Tmds Pain |
0.958 |
2001 — 2004 |
Hu, James C |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Protein Self-Assembly in Model Microorganisms @ Texas a&M University System
DESCRIPTION (provided by applicant): With complete genome sequences available, it is now possible to examine all of the proteins in a genome for involvement in multisubunit assemblies. How different proteins are able to form stable complexes is of fundamental interest from the perspective of protein structure and folding. In addition, identifying proteins that physically interact can provide valuable clues about their biochemical and biological functions. Mapping domains within proteins that are responsible for oligomerization is an important part of structure-function analysis. This application describes experiments to simultaneously identify and localize oligomerization domains on a genome-wide scale. Genomic DNA fragments from S. cerevisiae that encode motifs that can self-assemble will be identified by a genetic approach based on gene fusion methods using E. coli as a host. Libraries of yeast DNA fragments cloned as gene fusions to the DNA binding domain of bacteriophage lambda cI repressor will be subjected to selection for repressor activity, which requires assembly into dimers or higher oligomers. Initial characterization of candidate motifs will exploit the unique ability of the repressor system to distinguish between dimers and higher oligomeric forms in vivo. While the selection and characterization of oligomerization domains from yeast is in progress, the search will be extended to find self-assembling domains from two bacteria, E. coli and M. tuberculosis, and two filamentous fungi, N. crassa and A. fumigatus. Although the primary focus of this proposal is on homotypic interactions, methods will be developed to use combinations of libraries in E. coli-based two-hybrid systems to examine protein motifs from S. cerevisiae that are sufficient to form heterotypic complexes. Oligomerization domains will be expressed and purified from E. coli. Size exclusion chromatography and analytical ultracentrifugation will be used to determine their oligomerization states. The boundaries of the domains that are necessary and sufficient to form stable complexes will be determined by partial proteolysis, followed by analysis of protease resistant fragments by N-terminal peptide sequencing and mass spectrometry. Structures of soluble oligomerization domains will be determined by X-ray crystallography. Expression vectors will be developed to use the oligomerization domains as "dominant negative" inhibitors in S. cerevisiae and in E. coli. This work will contribute to human health by providing important insights into protein taxonomy, materials for protein design, new tools for genetic studies in model organisms (S. cerevisiae and E. coli) and important human pathogens (M. tuberculosis and A. fumigatus), and new drug targets based on protein-protein interactions.
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0.905 |
2009 — 2012 |
Hu, James C Sherlock, Gavin J Thomas, Paul D. [⬀] |
U24Activity Code Description: To support research projects contributing to improvement of the capability of resources to serve biomedical research. |
Ecolihub2.0: a Next-Generation E. Coli Model Organism Resource (Sri Proposal Ecu @ University of Southern California
DESCRIPTION (provided by applicant): Arguably the best-studied organism on earth, the bacterium Escherichia coli has been both the test bed and the beneficiary of genetic dissections, biochemical studies of proteins and metabolites, molecular biology manipulations and evolutionary experiments. More recently, E. coli has also been studied by and used to develop the rapidly advancing tools of genomics and systems biology, leading to a rapidly increasing body of data and computational tools for its analysis. Despite the critical importance of E. coli in uncovering fundamental biological truths and developing groundbreaking new technologies, there is still no online data resource that satisfies the diverse and sophisticated needs of the E. coli research community. To support the needs of this large research community, we propose to build the next generation web resource, EcoliHub2.0. EcoliHub2.0 will bring together and extend several existing software platforms to provide: 1) a powerful and intuitive user interface designed for biologists and using best practices of software engineering, 2) seamless access to state of the art tools for high-throughput omics data, 3) expert curation of the scientific literature for commonly-used laboratory strains of E. coli, 4) powerful comparative genomics tools for E. coli and other enteric bacteria such as Salmonella, 5) use of evolutionary relationships to examine other model organisms, enteric bacterial pathogens, and human biomedical conditions, 6) integration with systems biology tools for E. coli, 7) extension and further integration of EcoliWiki for community-based annotation and primary source for educational materials. Public Health Relevance: The EcoliHub2.0 resource will promote human health by supporting research on a key model system. Thanks to evolution and the NIH's half-century of investment in pound coli research, this microbe continues to teach us about basic cellular processes common to all life, from beneficial and harmful bacteria to healthy and diseased humans. EcoliHub2.0 will also advance the state of the art for genome data resources, providing cost-effective mechanisms that can be applied to the managing the coordination of diverse experts and resources for many NIH-sponsored projects.
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0.922 |
2010 — 2012 |
Hu, James C |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
An Ontology For Bacterial Phenotypes
DESCRIPTION (provided by applicant): Genome and metagenome sequencing efforts are producing a wealth of new information about microbes. Phenotypes are the observable traits resulting from genotypes and thus are a fundamental aspect of the biology of all organisms. Our ability to fully exploit the power of phenotypes for functional and comparative genomics in basic, applied, and clinical microbiology is hindered by the lack of a controlled terminology to describe and classify them. Ontologies are controlled vocabularies with defined relationships between terms. The overall goal of this project is to build a system for ontology-based annotation of bacterial phenotypes. The project will develop the necessary components and infrastructure, test the system on a well-characterized model system, and involve the relevant scientific communities in its development. The components are: 1) an Ontology for Microbial Phenotypes (OMP). 2) An extension of an existing ontology, the Evidence Code Ontology (ECO) to describe how OMP phenotypes were determined and cross referencing of ECO terms to a methods resource. 3) A pilot project to use the system to catalog phenotypes of mutations from E. coli, a well- understood bacterial model system. 4) a web site to help the scientific community find these new resources for bacterial phenotype annotation. 5) Outreach and education to promote the use of the system and to incorporate it into undergraduate and graduate education in genetics and microbiology. PUBLIC HEALTH RELEVANCE: An improved phenotype annotation system will have broad impacts relevant to the mission of NIH. The ability to correlate differences in gene content with important phenotypic differences between strains or microbial communities can help researchers target genes or organisms likely to be involved in virulence, drug resistance, and other important processes to infectious disease and human health. In addition, it can be used to elucidate the function of proteins involved in pathogenesis through comparative analysis based on phenotypes.
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0.908 |