Roles and molecular mechanisms of SUMO-interaction motifs and SUMOylation of retroviral integrase in mediating its cofactor binding and beyond

SUMO化是一种重要的蛋白质翻译后修饰，它调节蛋白质的生物学活性并与辅因子相互作用。已知SUMO化的蛋白质能够与其辅因子中存在的SUMO相互作用基序（西姆斯）结合，不同蛋白质之间的这种相互作用连接不同的信号通路并调节其生物学功能。HIV-1整合酶是一种SUMO化蛋白。此外，这种推定的SUMO化位点也发现在不同的动物逆转录病毒整合酶。 然而，SUMO化如何调节其生物学作用的完整映射和理解仍然是难以捉摸的。有趣的是，我们的序列分析进一步揭示了这种逆转录病毒蛋白中存在的三种西姆斯，这表明同一蛋白中存在的SUMO化和西姆斯可以协调在一起并调节其与其他细胞辅因子的通讯。

SUMOylation is an important posttranslational modification of proteins that regulates their biological activities and cross-talking with their cofactors. It is known that SUMOylated proteins are able to bind to a SUMO-interaction motif (SIMs) present in their cofactors and such cross-talking between different proteins links different signal pathways and regulate their biological fucntions. HIV-1 integrase has recently been shown to be a SUMOylated protein. Also, such putative SUMOylation sites were also found in different animal retroviral integrases. However, a complete mapping and understanding of how SUMOylation could regulate their biological actions still remain elusive. Interestingly, our sequence analysis further revealed three SIMs present in this retroviral protein, suggesting that the SUMOylation and SIMs present in the same protein may coordinate together and regulate its communication with other cellular cofactors.