title: Differential expression and regional distribution of steroid receptor coactivators SRC-1 and SRC-2 in brain and pituitary.
abstract: Members of the p160 family of steroid receptor coactivator proteins mediate the stimulatory effects on gene transcription brought about by nuclear receptors, which comprise all steroid receptors. Using in situ hybridization we have examined the neuroanatomical distribution of the messenger RNAs (mRNAs) for two functionally distinct splice variants of Steroid Receptor Coactivator 1 (SRC-1/NCoA-1) and of Steroid Receptor Coactivator 2 (SRC-2/NCoA-2/GRIP-1/TIF-2). Transcripts encoding these coactivators show highly differential expression patterns. SRC-2 mRNA is expressed at very low levels in brain, but shows expression in the anterior pituitary. SRC-la and le mRNA are expressed in many brain areas, including hippocampus, amygdala, hypothalamus, basal ganglia, and isocortex. Striking differences between SRC-1a and le expression were observed in several brain nuclei. Relative levels of SRC-1a mRNA were much higher in anterior pituitary, and the arcuate, paraventricular and ventromedial nucleus of the hypothalamus, the locus coeruleus and the trigeminal motor nucleus, all important targets of steroid hormones in the brain. SRC-le mRNA showed modest elevation of relative expression in the caudal nucleus accumbens (shell), basolateral amygdala, and some thalamic nuclei. The differential and uneven neuroanatomical distribution of these coactivators may underlie diversity and cell-specificity of steroid receptor mediated signals in the brain.
authors.affiliation: Division of Medical Pharmacology, Leiden/Amsterdam Center for Drug Research, The Netherlands. o.meijer@lacdr.leidenuniv.nl
authors.forename: O C
authors.initials: OC
authors.lastname: Meijer
authors.forename: P J
authors.initials: PJ
authors.lastname: Steenbergen
authors.forename: E R
authors.initials: ER
authors.lastname: De Kloet
mesh_terms: D000679:Amygdala / Q000737:chemistry; D000818:Animals; D001479:Basal Ganglia / Q000737:chemistry; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D001923:Brain Chemistry; D002540:Cerebral Cortex / Q000737:chemistry; D015870:Gene Expression; D006624:Hippocampus / Q000737:chemistry; D051548:Histone Acetyltransferases; D007031:Hypothalamus / Q000737:chemistry; D017403:In Situ Hybridization; D008297:Male; D056920:Nuclear Receptor Coactivator 1; D051958:Nuclear Receptor Coactivator 2; D015345:Oligonucleotide Probes; D010902:Pituitary Gland / Q000737:chemistry* / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar; D014018:Tissue Distribution; D014157:Transcription Factors / Q000235:genetics*
chemical_list: C498003:Ncoa2 protein, rat; D051958:Nuclear Receptor Coactivator 2; D015345:Oligonucleotide Probes; D012333:RNA, Messenger; D014157:Transcription Factors; D051548:Histone Acetyltransferases; D056920:Nuclear Receptor Coactivator 1