Cloning, characterization, and expression of the rat relaxin gene.
Relaxin, a hormone in the insulin superfamily, is synthesized by the corpus luteum of the rat ovary. Expression of relaxin precursor mRNA in rats is sharply induced after day 10 of pregnancy and plateaus on days 15 to 20 (parturition occurs on day 23). In an effort to understand this induction, we cloned the gene and carried out promoter analyses by transient transfection and chromatin immunoprecipitation methods. The single gene is 2.9 kilobases and is composed of two exons and one intron. There are alternative splice acceptor sites, 3 base pairs apart, which account for the inclusion of an extra codon in about 10% of the transcripts. The induction of transcription by day 15 was observed by the binding of polymerase II and histone H3 acetylation at the promoter region. There is a functional STAT binding site, about 3.8 kb upstream from the transcriptional start site, that is occupied by STAT3 on day 6 of pregnancy, when relaxin expression is minimal; on day 15, when expression is maximal, STAT3 is replaced by STAT5a. These data are consistent with STAT5 playing a role in the induction of relaxin expression.
Soloff
Melvyn S
MS
Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX 77555-1062, USA. msoloff@utmb.edu
Gal
Sangwan
S
Hoare
Sarasija
S
Peters
Carl A
CA
Hunzicker-Dunn
Mary
M
Anderson
Garland D
GD
Wood
Thomas G
TG
D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D002843:Chromatin / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D004247:DNA / Q000737:chemistry / Q000235:genetics; D005091:Exons; D005260:Female; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental; D005796:Genes / Q000235:genetics*; D006107:Granulosa Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D007438:Introns; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D011233:Precipitin Tests / Q000379:methods; D011247:Pregnancy; D011498:Protein Precursors / Q000235:genetics; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012065:Relaxin / Q000235:genetics* / Q000378:metabolism; D017422:Sequence Analysis, DNA; D024363:Transcription Initiation Site; D014162:Transfection
D002843:Chromatin; D011498:Protein Precursors; D011993:Recombinant Fusion Proteins; C034820:preprorelaxin; D012065:Relaxin; D004247:DNA; D008156:Luciferases