Progesterone-Induced Maturation and Down Regulation of Membrane Bound Na+, K+-ATPase

Progesterone induces maturation by releasing oocyte from G2 of MI cell cycle arrest. This process is rate limiting as it produces fertilizable eggs. Therefore, it draws a lot of attention. Na+, K+-ATPase is a membrane bound enzyme molecule that has known to have various functions. One of these functions is to act as receptor for Progesterone. In oocyte maturation to egg entirely depends on progesterone, a hormone that is known to reduce risk of cancer. Using EM Histo-cytochemical novel technique, we have shown that membrane bound Na+, K+-ATPase are gradually down-regulated following Progesterone-induced maturation. By Germinal Vesicle Break down, Na+, K+-ATPase is completely down-regulated from oolemma and only present in the narrow region of Germinal Vesicle Break Down. This is an important phenonmena as this down-regulation coincides with cell entering M-phase. Here, I also briefly introduce you to a technique that only localizes phosphate cleaving membrane bound Na+, K+-ATPase.