Characterization of LIM domain only 7(LMO7), a mitotic phosphoprotein

• Main Authors: Chih-Yun Chang, 張智雲
• Other Authors: none
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/17897176970140540274

碩士 === 慈濟大學 === 分子生物及細胞生物研究所 === 95 === Human LMO7, a nuclear membrane protein, has been shown to function as a transcription factor that can control expression of Emery-Dreifuss muscular dystrophy (EDMD) related genes. In our yeast two-hybrid screening, human LMO7 was identified to interact with the spindle checkpoint protein hMad1. We have generated and purified rabbit anti-LMO7 antibodies for the analysis. By in vitro binding assay, bacterially expressed hMad1 recombinant protein could interact with the purified hLMO7bFL recombinant protein that was expressed in insect cells. By the coimmunoprecipitation assay, we found endogenous hLMO7 could interact with endogenous hMad1 in the HeLa cells. We found that LMO7 protein levels were cell cycle-regulated and relatively low in late mitosis and early G1. Although LMO7 protein level did not fluctuate from S to M phase, LMO7 was phosphorylated in M phase but not in S phase. We have confirmed that endogenous hLMO7 or recombinant hLMO7bFL protein could be phosphorylated by PKA, Aurora A, GSK-3α, and GSK-3β but not by Aurora B and CyclinB1/Cdc2 in the in vitro assay and its possible phosphorylated residues were identified by the AP MALDI/MS. We propose that LMO7 phosphorylation was related to mitosis progression.