Park Miree, Jeon Sanghyun, Jeong Ji-Hye, Park Miseon, Lee Dong-Ryul, Yoon Tae Ki, Choi Dong Hee, Choi Youngsok
Dept. of Biomedical Science, CHA University, Seoul 135-081, Korea.
Fertility Center of CHA Gangnam Medical Center, CHA University, Seoul 135-081, Korea.
Dev Reprod. 2012 Dec;16(4):379-84. doi: 10.12717/DR.2012.16.4.379.
Lhx8 (LIM homeobox 8) gene encodes a LIM homeodomain transcriptional regulator that is preferentially expressed in germ cells and critical for mammalian folliculogenesis. However, Lhx8 DNA binding sequences are not characterized yet. We aimed to identify and characterize a cis-acting sequence of germ-cell specific transcriptional factor, Lhx8. To identify Lhx8 DNA binding element, Cyclic Amplification of Sequence Target (CAST) Analysis was performed. Electrophoretic Mobility Shift Assay (EMSA) was processed for the binding specificity of Lhx8. Luciferase assay was for the transcriptional activity of Lhx8 through identified DNA binding site. We identified a putative cis-acting sequence, TGATTG as Lhx8 DNA binding element (LBE). In addition, Lhx8 binds to the LBE with high affinity and augments transcriptional activity of luciferase reporter driven by artificial promoter containing the Lhx8 binding element. These findings indicate that Lhx8 directly regulates the transcription of genes containing Lhx8 binding element in oocytes during early folliculogenesis.
Lhx8（LIM同源框8）基因编码一种LIM同源结构域转录调节因子，该因子在生殖细胞中优先表达，对哺乳动物卵泡发生至关重要。然而，Lhx8的DNA结合序列尚未得到表征。我们旨在鉴定并表征生殖细胞特异性转录因子Lhx8的顺式作用序列。为了鉴定Lhx8的DNA结合元件，我们进行了序列靶标的循环扩增（CAST）分析。对Lhx8的结合特异性进行了电泳迁移率变动分析（EMSA）。荧光素酶测定用于检测Lhx8通过已鉴定的DNA结合位点的转录活性。我们鉴定出一个假定的顺式作用序列TGATTG作为Lhx8 DNA结合元件（LBE）。此外，Lhx8以高亲和力结合LBE，并增强由包含Lhx8结合元件的人工启动子驱动的荧光素酶报告基因的转录活性。这些发现表明，Lhx8在卵泡发生早期直接调节卵母细胞中含有Lhx8结合元件的基因的转录。
