Variation in the coding and 3′ untranslated regions of the porcine prolactin receptor short form modifies protein expression and function. (18th December 2013)

• Record Type: Journal Article
• Authors: Trott, Josephine F.; Freking, Bradley A.; Hovey, Russell C.
• Is Part Of: Animal genetics. Volume 45:Number 1(2014:Feb.)
• Page Start: 74
• Page End: 86
• Publication Date: 2013-12-18
• Subjects: Animal genetics -- Periodicals; 572.8
• DOI: 10.1111/age.12100
• Languages: English
• ISSNs: 0268-9146

Abstract

<abstract abstract-type="main" id="age12100-abs-0001"> <title>Summary</title> <p>The actions of prolactin (PRL) are mediated by both long (LF) and short isoforms (SF) of the PRL receptor (PRLR). Here, we report on a genetic and functional analysis of the porcine PRLR (pPRLR) SF. Three single nucleotide polymorphisms (SNPs) within exon 11 of the p<italic>PRLR</italic>‐SF give rise to four amino acid haplotypes of the intracellular domain. We identified the dimorphic insertion of a short interspersed repetitive DNA element (PRE‐1) along with 32 SNPs and four other insertion/deletion sites within the 3′ untranslated region (UTR) of p<italic>PRLR</italic>‐SF. The PRE‐1 element reduced protein translation <italic>in vitro</italic> by 75%, whereas the combination of 10 SNPs and one insertion/deletion decreased translation by 50%. Full‐length cDNAs for all four haplotypes of p<italic>PRLR</italic>‐SF were cloned behind the elongation factor 1‐alpha promoter and functionally analyzed <italic>in vitro</italic>. None of the haplotypes could initiate transcription from the ß‐casein promoter, whereas all four were dominant negatives against PRL‐activation of the pPRLR‐LF. Two of the haplotypes completely inhibited pPRLR‐LF activity at a four‐fold excess, whereas the others required a six‐fold excess to impart the same effect. The ligand binding affinities of the pPRLR‐SF haplotypes did not differ. Expression of the p<italic>PRLR</italic>‐SF increased linearly during gestation in the endometrium and was hormonally regulated in a tissue‐specific manner in the mammary glands and uterus. In conclusion, we identified a PRE‐1 and other SNPs in the p<italic>PRLR</italic>‐SF 3′ UTR that reduce protein expression and four haplotypes of the pPRLR‐SF that suppress pPRLR‐LF signaling and may differentially impact the phenotypic effects of PRL <italic>in vivo</italic>.</p> </abstract>