Expression of Endometrial Protein Kinase A During Early Pregnancy in Bonnet Monkeys (Macaca radiata)1

Abstract

Embryo-induced signaling pathways are considered to be important for initiation and sustenance of pregnancy. However many of these pathways remain to be deciphered in primates. In the present study, differential display RT-PCR was used to identify genes or gene fragments that are differentially expressed in endometrium of bonnet monkeys (Macaca radiata) on Day 6 of pregnancy. Of several fragments found to be differentially expressed, a fragment of 567 base pair (named GG1) was characterized in detail. GG1 was highly represented in endometrium of pregnant animals compared with that of nonpregnant animals. Sequencing analysis revealed homology of this fragment to exons 7, 8, 9, and 10 and surprisingly to intron 6 of cAMP-dependent protein kinase A (PKA) regulatory type I alpha (tissue-specific extinguisher 1) (PRKAR1A). The increased expression of this fragment in gestational endometrium was confirmed by quantitative PCR studies. Two transcripts of 3.0 kilobase (kb) and 1.5 kb were detected in Northern blot probed with labeled GG1. Protein expressions of alpha regulatory (PRKAR1A) and alpha catalytic (PRKCA) subunits of PKA were also higher in gestational endometrium compared with that in nongestational endometrium. Further in vitro studies using human endometrial explants demonstrated regulation of PRKAR1A (or GG1) and prostaglandin-endoperoxide synthase 2 or cyclooxygenase 2 (PTGS2) by estradiol. This is the first study to date on the differential expression of PKA in primate endometrium during early pregnancy and its in vitro regulation by estradiol.

HSP90 Antibodies: A Detrimental Factor Responsible for Ovarian Dysfunction

“…Real‐time PCR was carried out using Taqman primers for 18S RNA VIC labeled; Gja1 FAM labeled; (Assay Id: Mm_00439105); and Nobox FAM labeled; (Assay Id: Mm_00453743; Applied Biosystems, Foster City, CA, USA) in 7900 HT Real‐time PCR machine. The relative fold change in the level of expression was quantified using ΔΔct values as described earlier . 18S r RNA served as a loading control, and the expression of gene of interest was normalized to it.…”

The evolution of menstruation: A new model for genetic assimilation

“…A scratch to the uterus is enough to initiate decidualization in the progesterone-primed rodent uterus, but fetus-derived cytokines are also suspected to be involved in decidualization (see [28,29]). While the mechanisms are not fully understood, there are multiple signaling pathways turned on in the uterus during decidualization induced by the fetus, including the BMP2, WNT, JAK/STAT, and cAMP dependent pathways [30–35]. While the mechanisms of SD are even less understood, we do know that only signals from the mother, i.e.…”

“…On the other hand it is tempting to speculate that the second, cAMP dependent, pathway is signaling pathway activated by the fetus in non-menstruating species, and was taken over by maternal signals in species with SD. It is clear that PKA and cAMP-stimulating agents are unpregulated at the implantation site and necessary for decidualization in the number of placental mammals, including rodents, nonhuman primates, and hoofed animals [35,43–47]. Hence, the evolution of SD might have proceeded via maternal activation of the cAMP signaling pathway that ancestrally was activated by the fetus.…”

Homeobox genes in endometrium: from development to decidualization

“…The morphological changes in the endometrium are also paralleled by several molecular changes that include increased expression of estrogen receptor alpha (ER alpha), transforming growth factor beta (TGFb 2), Interleukin 6 (IL-6), Glycodelin and Integrin's in the endometrium of bonnet monkeys in presence of an embryo (Nimbkar-Joshi et al, 2012;2005 b,c;Rosario et al, 2008).We also discovered a novel isoform of protein kinase a regulatory subunit which is transcribed at higher levels in endometria of monkeys in presence of an embryo (Rosario et al, 2009). Interestingly, comparable molecular changes are also observed in endometria of baboons infused with embryonic factors (human CG and IL1b) and these are summarized by us previously (Modi et al, 2012).…”