Expression and subcellular distribution of the active form of c-Src tyrosine kinase in differentiating human endometrial stromal cells.
Decidual growth factors and locally produced cytokines are thought to activate specific phosphorylation signalling pathway(s), thereby eliciting a variety of decidual functions. We have previously reported the activation of c-Src tyrosine kinase during ovarian steroid-induced decidualization of cultured human endometrial stromal cells. As chicken c-Src is known to be activated upon dephosphorylation of tyrosine 527 (Y527, corresponding to Y530 in human), we here employed a monoclonal antibody, clone 28, directed against the active form of human c-Src whose Y530 is dephosphorylated, and investigated whether c-Src became dephosphorylated at Y530 and thereby activated during decidualization. We found that the active form of c-Src was up-regulated and demonstrated increased kinase activity during in-vitro decidualization. Immunohistochemistry revealed that decidual cells in early pregnancy decidua were intensely stained with clone 28 when compared with the stromal cells in the non-pregnant endometrium. Moreover, the active form of c-Src translocated from a perinuclear region to the cytoplasm upon decidualization. Thus, the Y530 dephosphorylation, kinase activation, and subcellular translocation of c-Src may be intracellular signalling events associated with decidualization in vivo as well as in vitro.
Yamamoto
Yurie
Y
Department of Obstetrics and Gynecology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.
Maruyama
Tetsuo
T
Sakai
Nozomi
N
Sakurai
Rei
R
Shimizu
Aki
A
Hamatani
Toshio
T
Masuda
Hirotaka
H
Uchida
Hiroshi
H
Sabe
Hisataka
H
Yoshimura
Yasunori
Y
D000081247:CSK Tyrosine-Protein Kinase; D002454:Cell Differentiation / Q000502:physiology*; D003656:Decidua / Q000166:cytology / Q000254:growth & development; D004717:Endometrium / Q000166:cytology / Q000254:growth & development*; D005260:Female; D006801:Humans; D010766:Phosphorylation; D011247:Pregnancy; D011505:Protein-Tyrosine Kinases / Q000096:biosynthesis / Q000235:genetics*; D017154:Stromal Cells / Q000378:metabolism; D019061:src-Family Kinases
D011505:Protein-Tyrosine Kinases; D000081247:CSK Tyrosine-Protein Kinase; D019061:src-Family Kinases; C000631346:CSK protein, human