Eric K. Richfield, MD - US grants

The Molecular and Cellular Imaging Core (MCIC) will be a local and regional resource for tissue-based image analysis. The MCIC will provide state-of-the-art facilities for qualitative and quantitative film densitometry and microscopic tissue analyses for investigators in the field of aging research. The MCIC will provide training to interested users or perform selected analyses of approved projects. Approved projects are anticipated from local and regional investigators. Applications for MCIC use will additionally solicited form aging-related scientists unbiased stereology, tiled mapping, and 3-D reconstruction. Tissue based techniques including quantitative receptor autoradiography and in situ histochemistry (ISHH) will be performed on a reviewed basis for aging-related projects. These types of analyses and techniques require expertise that may not be available to many laboratories involving in aging studies. Novel in situ hybridization probes and protocols will be developed, validated, and made available to local, regional and national investigators. In collaboration with the Microarray Analysis Core (MAC) and the Gene Expression Vector Core (GEVC) we will develop, validate, and provide five probes to cellular housekeeping genes for ISHH that can be used for validation of data obtained from microarrays. Oligonucleotide or cRNA probes to specific genes of interest to local, regional, or national researchers will be designed or cloned, to be of interest in human tissue or animal models of age-related diseases. These novel genes will be identified by microarray analyses or traditional methods of novel gene identification. As developed, our web site will contain a list of services and probes available to potential users and copies of all protocols for image analyses and ISSH.

DESCRIPTION (provided by applicant) The cause(s) of idiopathic Parkinson's disease (PD) in man remains unknown, but reflects an individual's combined risks associated with genetic background, life-long environmental exposures and age. The role of genotype in contributing to PD varies depending on the presence of a genetic mutation or a polymorphism that contributes to the alteration of a gene product or function. The role of the environment in idiopathic PD also varies from strong for certain neurotoxicants such as MPTP to weaker for pesticides and heavy metals. The interaction between genetic and environmental risk factors in man and mouse is poorly understood. Mouse models of PD based on genetic manipulations, neurotoxicant exposure or combined genetic and neurotoxicant exposures are useful for exploring mechanisms of neuronal loss and dysfunction. Recent breakthroughs in several areas of genetics and biotechnology will help define the roles of genes and neurotoxicants in PD. We will map Quantitative Trait Loci (QTL) in mice that play a role in mouse models of PD. We will measure baseline locomotor activity, striatal dopamine and metabolite levels, and total substantia nigra pars compacta (SNpc) neuron number in 15 inbred strains of mice treated with saline or with MPTP, paraquat, or paraquat plus maneb. We will use the association mapping procedure and mouse single nucleotide polymorphism (SNP) database created by Peltz and colleagues to map QTL for these traits in the absence or presence of a neurotoxicant. We will use permutation tests to generate appropriate experiment-wise thresholds for declaring a QTL significant. We propose a novel and innovative method for mapping QTL contributing to the adverse effects of environmental neurotoxicants resulting in the PDP in mice. Mapping of QTL will ultimately lead to a variety of studies in mice resulting in the identification of the specific genes involved and their mechanism of action in contributing to PD. Our ultimate goal is to identify specific genes, their polymorphisms, and how they interact with the environment in predisposing man to PD.