Hormonally Modulated S-Nitrosation of Profilin-1 and Myosin Regulatory Light Polypeptide 9

Abstract

The roles of estrogen and progesterone are highly regulated during the different phases of pregnancy. The roles of these hormones and the cellular signal transduction of labor contractions are well understood; however, the initiation of spontaneous preterm labor contractions is still unknown in research today. The levels of estrogen and progesterone are known to increase, and myosin regulatory light polypeptide 9 and profilin-1 is known to be upregulated and S-nitrosated in preterm laboring myometrium. We hypothesize that levels of estrogen and progesterone may have an effect on posttranslational modification of myosin regulatory light polypeptide 9 and profilin-1. Estrogen and Progesterone are highly regulated during the different phases of pregnancy. Using western blot and biotin switch technique, we isolated S-nitrosated proteins, myosin regulatory light polypeptide 9 and profilin-1, from hormonal and non hormonal growth arrested cells lines of Pregnant Human Uterine Smooth Muscle Cell human Telomerase Reverse Transcriptase (PHUSMC hTRT) for analysis. The results indicated that myosin light polypeptide 9 had 1.45 and 1.68 fold increases (hormone and non-hormone) in Snitrosation. Profilin-1 had 2.94 and 5.07 fold increases (hormone and non-hormone) S-nitrosation.