Proteomic Approach Identifies Alterations in Cytoskeletal Remodelling Proteins during Decidualization of Human Endometrial Stromal Cells

Abstract

Decidualization is a tissue remodelling process within the uterus in preparation for embryo implantation and pregnancy. In this study we isolated primary human endometrial stromal cells and stimulated decidualization with cAMP. We then used 2D- differential in-gel electrophoresis (DIGE) to identify proteins induced by decidualization. Eighty-eight out of 2714 spots were differentially regulated, 18 of which were assigned clear identities by mass spectrometry. Many of these are proteins known to be associated with cell structure and cytoskeletal remodelling. We validated five of these proteins by Western blot and immunohistochemistry on human endometrial tissue. The validated proteins are caldesmon 1, src substrate contactin 8, tropomyosin alpha-4 chain, protein disulfide isomerase 1A, and LIM and SH3 domain protein. With the exception of caldesmon 1, none of the identified proteins have previously been associated with decidualization. This study provides insight into our understanding of decidualization, which is important for successful embryo implantation and establishment of pregnancy.

Cytoskeletal remodelling proteins identified in fetal-maternal interface in pregnant women and rhesus monkeys

“…Similarly TPM4, SRC8 and PDIA1 proteins were not as distinct in the rhesus monkey compared to women. Previously TPM4, SRC8 and PDA1 were detected in the decidual cells in the late secretory phase of the menstrual cycle (Paule et al 2010). We now observed the proteins in the decidua of pregnant women.…”

“…PDIA1 localized to the decidual cells and the spiral arterioles during the late secretory phase (Paule et al 2010) and early in pregnancy. However PDIA1 is only present in glandular epithelium in the trimester of pregnancy and not in the late secretory phase (Paule et al 2010). This suggests PDIA1 may serve an important functional role early in pregnancy.…”

“…Our previous proteomic study identified tropomyosin alpha-4 chain (TPM4), protein disulfide isomerase A1 (PDIA1) and src substrate cortactin 8 (SRC8) as novel cytoskeletal remodelling proteins that were specifically up regulated in decidual cells in the late secretory phase of the menstrual cycle in women (Paule et al 2010). In this study we determined whether TPM4, PDIA1 and SRC8 were present in the decidual cells within the fetal-maternal interface during early pregnancy in women.…”

Proteomic Analysis of Menstrual Blood

“…7, supplemental Table S4) are consistent with the biological processes known to occur in the late secretory phase of the menstrual cycle. For as the secretory endometrium progresses toward predecidua and prepares for blastocyst implantation, nuclei becomes euchromatic, the number of ribosomes increases and cell cytoplasms fills with additional cytoskeletal elements (6,8,30). At this time endometrial granulocytes appear in order to suppress other immune cells and thereby protect a genetically distinct implanting embryo from its mother's immune defense system (6,8).…”

Expression and activation of the membrane-cytoskeleton protein ezrin during the normal endometrial cycle

“…In the event of a barren cycle, when the corpus luteum expires, there is shedding of the upper endometrium (functionalis) and the next endometrial cycle begins with the glandular cells and stroma of the basalis layer beginning to proliferate and re-epithelize the open wound (11,12). All of these activities require cellular and tissue remodeling (13).…”