FGF2 stimulates SDF-1 expression through the Erm transcription factor in Sertoli cells.
Ets-related molecule (Erm) is a member of the Ets transcription factor family. Erm is known to be an important factor for the self-renewal of Spermatogonial stem cells (SSCs) and the maintenance of spermatogenesis. We investigated the molecular mechanism of Erm regulation on SDF-1 in TM4 Sertoli cells. Erm and Sdf-1 levels were up-regulated after FGF2 treatment in TM4 cells, whereas these levels were significantly decreased by FGF2 in ST2 bone marrow stromal cells. Knockdown of Erm by siRNA in the presence of FGF2 decreased the Sdf-1 levels in TM4 cells. The expression levels of Erm were similar and Erm overexpression increased the Sdf-1 in both TM4 and ST2 cells. FGFR subtype analysis revealed that FGFR4 was expressed in TM4 cells but not in ST2 cells. A blocking experiment also confirmed that FGFR4 is partly responsible for the up-regulation of Erm and SDF-1 induced by FGF2 stimulation in TM4 cells. FGF2 and ERM increased the activity of Sdf-1 gene promoter region in a dose-dependent manner. EMSA revealed that ERM strongly binds to the -846 to -851 nucleotide region of the potential Ets binding site (EBS) in the Sdf-1 promoter. In addition, CXCR4, the SDF-1 receptor, was expressed in spermatogonia and Sertoli cells in the seminiferous tubules of the mouse testis. Our results indicate that ERM directly regulates Sdf-1 gene expression by interacting with its cis-acting element in response to FGF2 stimulation in TM4 cells.
Yoon
Kyung-Ae
KA
Department of Biochemistry, School of Dentistry, Kyungpook National University, Daegu, South Korea.
Chae
Young-Mi
YM
Cho
Je-Yoel
JY
D000818:Animals; D001665:Binding Sites; D001854:Bone Marrow Cells / Q000378:metabolism; D019556:COS Cells; D002460:Cell Line; D054377:Chemokine CXCL12 / Q000235:genetics / Q000378:metabolism*; D002522:Chlorocebus aethiops; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D006801:Humans; D008297:Male; D051379:Mice; D011401:Promoter Regions, Genetic; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D051499:Receptor, Fibroblast Growth Factor, Type 4 / Q000378:metabolism; D019718:Receptors, CXCR4 / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D012708:Sertoli Cells / Q000378:metabolism*; D013093:Spermatogonia / Q000378:metabolism; D013234:Stem Cells / Q000378:metabolism; D017154:Stromal Cells / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D015854:Up-Regulation
C514936:CXCR4 protein, mouse; D054377:Chemokine CXCL12; C515256:Cxcl12 protein, mouse; D004268:DNA-Binding Proteins; C513242:Etv5 protein, mouse; D034741:RNA, Small Interfering; D019718:Receptors, CXCR4; D011994:Recombinant Proteins; D014157:Transcription Factors; D016222:Fibroblast Growth Factor 2; C496372:Fgfr4 protein, mouse; D051499:Receptor, Fibroblast Growth Factor, Type 4