title: Cell-type specific oxytocin gene expression from AAV delivered promoter deletion constructs into the rat supraoptic nucleus in vivo.
abstract: The magnocellular neurons (MCNs) in the hypothalamus selectively express either oxytocin (OXT) or vasopressin (AVP) neuropeptide genes, a property that defines their phenotypes. Here we examine the molecular basis of this selectivity in the OXT MCNs by stereotaxic microinjections of adeno-associated virus (AAV) vectors that contain various OXT gene promoter deletion constructs using EGFP as the reporter into the rat supraoptic nucleus (SON). Two weeks following injection of the AAVs, immunohistochemical assays of EGFP expression from these constructs were done to determine whether the EGFP reporter co-localizes with either the OXT- or AVP-immunoreactivity in the MCNs. The results show that the key elements in the OT gene promoter that regulate the cell-type specific expression the SON are located -216 to -100 bp upstream of the transcription start site. We hypothesize that within this 116 bp domain a repressor exists that inhibits expression specifically in AVP MCNs, thereby leading to the cell-type specific expression of the OXT gene only in the OXT MCNs.
authors.affiliation: Laboratory of Neurochemistry, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Raymond L
authors.initials: RL
authors.lastname: Fields
authors.forename: Todd A
authors.initials: TA
authors.lastname: Ponzio
authors.forename: Makoto
authors.initials: M
authors.lastname: Kawasaki
authors.forename: Harold
authors.initials: H
authors.lastname: Gainer
mesh_terms: D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism; D000229:Dependovirus / Q000378:metabolism*; D005091:Exons / Q000235:genetics; D005786:Gene Expression Regulation; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007438:Introns / Q000235:genetics; D008297:Male; D009928:Organ Specificity / Q000235:genetics; D009995:Osmosis; D010121:Oxytocin / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D017384:Sequence Deletion / Q000235:genetics*; D013238:Stereotaxic Techniques; D013495:Supraoptic Nucleus / Q000166:cytology / Q000378:metabolism*
chemical_list: C485184:enhanced green fluorescent protein; D001127:Arginine Vasopressin; D049452:Green Fluorescent Proteins; D010121:Oxytocin