XCI-escaping gene KDM5C contributes to ovarian development via downregulating miR-320a
HUMAN GENETICS
Authors: Sun, Yi-Xi; Zhang, Yi-Xin; Zhang, Dan; Xu, Chen-Ming; Chen, Song-Chang; Zhang, Jun-Yu; Ruan, Ye-Chun; Chen, Feng; Zhang, Run-Ju; Qian, Ye-Qing; Liu, Yi-Feng; Jin, Lu-Yang; Yu, Tian-Tian; Xu, Hai-Yan; Luo, Yu-Qin; Liu, Xin-Mei; Sun, Fei; Sheng, Jian-Zhong; Huang, He-Feng
Abstract
Mechanisms underlying female gonadal dysgenesis remain unclarified and relatively unstudied. Whether X-chromosome inactivation (XCI)-escaping genes and microRNAs (miRNAs) contribute to this condition is currently unknown. We compared 45,X Turner Syndrome women with 46,XX normal women, and investigated differentially expressed miRNAs in Turner Syndrome through plasma miRNA sequencing. We found that miR-320a was consistently upregulated not only in 45,X plasma and peripheral blood mononuclear cells (PBMCs), but also in 45,X fetal gonadal tissues. The levels of miR-320a in PBMCs from 45,X, 46,XX, 46,XY, and 47,XXY human subjects were inversely related to the expression levels of XCI-escaping gene KDM5C in PBMCs. In vitro models indicated that KDM5C suppressed miR-320a transcription by directly binding to the promoter of miR-320a to prevent histone methylation. In addition, we demonstrated that KITLG, an essential gene for ovarian development and primordial germ cell survival, was a direct target of miR-320a and that it was downregulated in 45,X fetal gonadal tissues. In conclusion, we demonstrated that downregulation of miR-320a by the XCI-escaping gene KDM5C contributed to ovarian development by targeting KITLG.
Phosphorylation and nuclear translocation of integrin beta 4 induced by a chemical small molecule contribute to apoptosis in vascular endothelial cells
APOPTOSIS
Authors: Ge, Di; Kong, Xiangqian; Liu, Weiyong; Zhao, Jing; Su, Le; Zhang, Shangli; Zhang, Yun; Zhao, Baoxiang; Miao, Junying
Abstract
Integrin beta 4 and its Y-1494 phosphorylation play an important role in cell signaling. We found a small molecule, ethyl1-(3-(4-chlorophenoxy)-2-hydroxypropyl)-3-(4-chlorophenyl)-1H-pyrazole-5-carboxylate (ECPC), that could elevate the levels of KIT ligand (KITLG), interleukin 8 (IL-8), prostaglandin-endoperoxide synthase 2 (PTGS2) and activating transcription factor 3 (ATF3) and promote apoptosis in vascular endothelial cells (VECs) through integrin beta 4. We investigated the underlying mechanism of integrin beta 4 participating in this process. ECPC treatment increased the phosphorylation of Y-1494 in the integrin beta 4 cytoplasmic domain via a well-known receptor tyrosine kinase, fibroblast growth factor receptor 1 (FGFR1), and integrin beta 4 translocated from the cytoplasm to nucleus. With suppression of Y-1494 phosphorylation by FGF-2 or siRNA of FGFR1, ECPC failed to promote integrin beta 4 nuclear translocation and could not increase the expression of KITLG, IL-8, PTGS2 or ATF3. Y-1494 phosphorylation and nuclear translocation of integrin beta 4 may be important during ECPC-induced apoptosis in VECs.