Changes in prolactin receptor expression during pregnancy in the mouse ovary.

Abstract

We have isolated the cDNA encoding the cytoplasmic domain of a long form of the mouse PRL receptor (PRL-R). The mRNA for this long form PRL-R and the three mRNAs encoding short mouse PRL-R that have been previously characterized are all expressed in both the liver and ovary. The relative amounts of these receptor forms differ between tissues, however. In addition, the structure of one of the short receptor forms may not be identical in the liver and ovary. Within the ovary, the abundance and sites of synthesis of the four PRL-R mRNAs vary during pregnancy. Expression of the two most abundant PRL-R mRNAs increases significantly at midgestation. Expression of PRL-R mRNA is detected in the corpus luteum throughout pregnancy, while increased receptor mRNA levels are evident in the granulosa cells of a subset of Graafian follicles toward the end of pregnancy and during lactation. Some differences are also observed in the expression patterns of the individual receptor forms. Most notably, one of the short form PRL-R mRNAs is uniquely detected in atretic follicles in early to midgestation.

Genomewide Discovery and Classification of Candidate Ovarian Fertility Genes in the Mouse

“…All 16 of the previously described adult ovarian factors are known to be specifically expressed in granulosa cells, corpora lutea, or thecal cells; none are oocyte specific (supplemental Table 1 at http:/ / www.genetics.org/supplemental/). Consistent with their expression in late follicles or corpora lutea, many play fundamental roles in steroid metabolism, including Akr1c18 (involved in progesterone catabolism) (Vergnes et al 2003), Cyp11a1 (Hu et al 2002), Cyp17a1 (Gray et al 1996), LH receptor (Mcfarland et al 1989), prostaglandin F receptor (Sugatani et al 1996), prolactin receptor (Clarke and Linzer 1993), steroidogenic acute regulatory protein (Star) (Clark et al 1995), and endothelial lipase (Ishida et al 2003;Ma et al 2003). Other previously described factors include anti-müllerian hormone (Durlinger et al 1999) and secreted frizzled-related sequence protein 4 (Hsieh et al 2005).…”

Functional Characterization of the Intermediate Isoform of the Human Prolactin Receptor

“…In the mouse, for example, examination of the transcripts of both short and long isoforms showed variation of expression in a tissue-specific manner, depending on the stage of the estrous cycle, pregnancy, and lactation (48,79). This variable expression suggests differences in the physiological roles of PRLr isoforms and co-transfection experiments utilizing different PRLr isoforms further support this hypothesis.…”

Interactions between prolactin and kisspeptin to control reproduction

“…Both short and long isoforms of PRLRs have been described to be expressed in the granulosa, interstitial and luteal cells of the ovaries, and the endometrium, myometrium and decidua in the uterus (24)(25)(26). Estradiol is the main ovarian hormone that stimulates prolactin secretion.…”

“…Estradiol acts at the pituitary level to modulate prolactin gene expression and at the hypothalamus to modulate the activity of neurons known to be prolactin responsive (1,9). Depending on the hormonal milieu, PRLRs expression in several tissues (e.g., the ovaries, uterus and hypothalamus) may change along the estrous cycle or during pregnancy and lactation (24,25). In the ovaries, prolactin acts in concert with gonadotropins to stimulate progesterone production by luteal cells and to induce the increase in progesterone receptor expression in the uterus.…”