Progesterone receptor membrane component-1 (PGRMC1) and PGRMC-2 interact to suppress entry into the cell cycle in spontaneously immortalized rat granulosa cells.

نویسندگان

  • John J Peluso
  • Daniel Griffin
  • Xiufang Liu
  • Meghan Horne
چکیده

Progesterone receptor membrane component 1 (PGRMC1) and PGRMC2 are expressed in rat granulosa cells and spontaneously immortalized granulosa cells (SIGCs) but their biological roles are not well defined. The present studies demonstrate that depleting either Pgrmc1 or Pgrmc2 in SIGCs increases entry into the cell cycle but does not increase cell proliferation. Rather, PGRMC1 and/or PGRMC2-deplete cells accumulate in metaphase and undergo apoptosis. Because both PGRMC1 and PGRMC2 localize to the mitotic spindle, their absence likely accounts for cells arresting in metaphase. Moreover, pull-down assays, colocalization studies and in situ proximity ligation assays (PLA) indicate that PGRMC1 binds PGRMC2. Disrupting the PGRMC1:PGRMC2 complex through the use of siRNA or the cytoplasmic delivery of a PGRMC2 antibody increases entry into the cell cycle. Conversely, overexpressing either PGRMC1-GFP or GFP-PGRMC2 fusion protein inhibits entry into the cell cycle. Subsequent studies reveal that depleting PGRMC1 and/or PGRMC2 reduces the percentage of cells in G0 and increases the percentage of cells in G1. These observations indicate that in addition to their role at metaphase, PGRMC1 and PGRMC2 are involved in regulating entry into the G1 stage of the cell cycle. Interestingly, both PGRMC1 and PGRMC2 bind GTPase-activating protein-binding protein 2 (G3BP2) as demonstrated by pull-down assays, colocalization assays, and PLAs. G3bp2 siRNA treatment also promotes entry into the G1 stage. This implies that dynamic changes in the interaction among PGRMC1, PGRMC2, and G3BP2 play an important protein regulating the rate at which SIGCs enter into the cell cycle.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Progesterone regulation of progesterone receptor membrane component 1 (PGRMC1) sumoylation and transcriptional activity in spontaneously immortalized granulosa cells.

Progesterone (P4) receptor membrane component (PGRMC)1 is detected as a 22-kDa band as well as higher molecular mass bands (>50 kDa) in spontaneously immortalized granulosa cells. That these higher molecular mass bands represent PGRMC1 is supported by the findings that they are not detected when either the primary antibody is omitted or the PGRMC1 antibody is preabsorbed with recombinant PGRMC1...

متن کامل

Expression of progesterone receptor membrane component-2 within the immature rat ovary and its role in regulating mitosis and apoptosis of spontaneously immortalized granulosa cells.

Progesterone receptor membrane component 2 (Pgrmc2) mRNA was detected in the immature rat ovary. By 48 h after eCG, Pgrmc2 mRNA levels decreased by 40% and were maintained at 48 h post-hCG. Immunohistochemical studies detected PGRMC2 in oocytes and ovarian surface epithelial, interstitial, thecal, granulosa, and luteal cells. PGRMC2 was also present in spontaneously immortalized granulosa cells...

متن کامل

Progesterone increases rat neural progenitor cell cycle gene expression and proliferation via extracellularly regulated kinase and progesterone receptor membrane components 1 and 2.

Progesterone receptor (PR) expression and regulation of neural progenitor cell (NPC) proliferation was investigated using NPC derived from adult rat brain. RT-PCR revealed that PRA mRNA was not detected in rat NPCs, whereas membrane-associated PRs, PR membrane components (PGRMCs) 1 and 2, mRNA were expressed. Progesterone-induced increase in 5-bromo-2-deoxyuridine incorporation was confirmed by...

متن کامل

Progesterone inhibits apoptosis in part by PGRMC1-regulated gene expression.

Progesterone receptor membrane component-1 (PGRMC1) is present in both the cytoplasm and nucleus of spontaneously immortalized granulosa cells (SIGCs). PGRMC1 is detected as a monomer in the cytoplasm and a DTT-resistant PGRMC1 dimer in the nucleus. Transfected PGRMC1-GFP localizes mainly to the cytoplasm and does not form a DTT-resistant dimer. Moreover, forced expression of PGRMC1-GFP increas...

متن کامل

Progesterone receptor membrane component 1 and its role in ovarian follicle growth

Progesterone (P4) is synthesized in the ovary and acts directly on granulosa cells of developing ovarian follicles to suppress their rate of mitosis and apoptosis. Granulosa cells do not express nuclear progesterone receptor (PGR) but rather progesterone receptor membrane component-1 (PGRMC1). PGRMC1 binds P4 and mediates P4's actions, as evidenced by PGRMC1 siRNA studies. PGRMC1 acts by bindin...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:
  • Biology of reproduction

دوره 91 5  شماره 

صفحات  -

تاریخ انتشار 2014