National Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin 9, Ireland.
FEBS Open Bio. 2013 Sep 21;3:433-7. doi: 10.1016/j.fob.2013.09.005. eCollection 2013.
The human LINE-1/L1 ORF2 protein is a multifunctional enzyme which plays a vital role in the life cycle of the human L1 retrotransposon. The protein consists of an endonuclease domain, followed by a central reverse transcriptase domain and a carboxy-terminal C-domain with unknown function. Here, we explore the nucleic acid binding properties of the 180-amino acid carboxy-terminal segment (CTS) of the human L1 ORF2p in vitro. In a series of experiments involving gel shift assay, we demonstrate that the CTS of L1 ORF2p binds RNA in non-sequence-specific manner. Finally, we report that mutations destroying the putative Zn-knuckle structure of the protein do not significantly affect the level of RNA binding and discuss the possible functional role of the CTS in L1 retrotransposition.
人类 LINE-1/L1 ORF2 蛋白是一种多功能酶，在人类 L1 反转录转座子的生命周期中起着至关重要的作用。该蛋白由一个内切酶结构域、一个中央逆转录酶结构域和一个羧基末端 C 结构域组成，后者具有未知功能。在这里，我们在体外探索了人类 L1 ORF2p 的 180 个氨基酸羧基末端片段（CTS）的核酸结合特性。在一系列涉及凝胶迁移分析的实验中，我们证明 L1 ORF2p 的 CTS 以非序列特异性的方式结合 RNA。最后，我们报告说，破坏蛋白质假定的 Zn 指结构的突变不会显著影响 RNA 结合水平，并讨论了 CTS 在 L1 反转座中的可能功能作用。
