Structural biology of host factors affecting retroviral integration

越来越清楚的是，参与逆转录病毒整合的一种重要宿主细胞蛋白是晶状体上皮源性生长因子(LEDGF/p75)，这是一种转录共激活因子，已被证明影响艾滋病毒整合酶的靶点选择(Ciuffi等人，2005年；Llano等人，2006年)。LEDGF直接与HIV整合酶相互作用，并被认为是连接整合前复合体和染色质的纽带。最近，LEDGF的整合酶结合区和HIV整合酶的催化域的共晶结构已经被确定(Cherepanov等人，2005年)。然而，目前还不清楚LEDGF如何与染色质相互作用，并将整合酶定向到其作用部位。我们将结构上的注意力集中在LEDGF的N-末端结构域上，LEDGF是PWWP家族蛋白质的成员。这个N-末端结构域被假设与裸DNA结合，但最近的数据表明，它可能与其他染色质元件结合(Botbol等人，2008年)。特别是，LEDGF的PWWP结构域与都铎家族蛋白质的相似性向我们表明，它可能与组蛋白尾部的甲基赖氨酸残基结合。我们已经表达和纯化了几个包含这个结构域的结构，并利用这个结构域与从鸡红细胞中纯化的核小体和修饰的多肽进行了结合研究。与DNA和多肽络合的LEDGF PWWP结构域的结晶实验正在进行中。 Botbol，Y.，Raghavenra，N.K.，Rahman，S.，Engelman，A.和Lavigne，M.(2008)核酸研究报告36,1237-1246。 首页--期刊主要分类--期刊细介绍--期刊题录与文摘--期刊详细内容娜塔莉。阿卡德。SCI。美国第102,17308-17313。 Ciuffi，A.，等人。(2005)《自然医学》。11,1287-1289。 Llano，M.等人。(2006)科学314,461-464。

It has become increasingly clear that an important host cell protein involved in retroviral integration is lens-epithelium-derived growth factor (LEDGF/p75), a transcriptional coactivator that has been shown to influence target site selection by HIV integrase (Ciuffi et al., 2005; Llano et al., 2006). LEDGF interacts directly with HIV integrase, and has been proposed to act as a tether that links pre-integration complexes to chromatin. Recently, the co-crystal structure of the integrase-binding region of LEDGF and the catalytic domain of HIV integrase has been determined (Cherepanov et al., 2005). However, it is not yet understood how LEDGF interacts with chromatin and directs integrase to its site of action. We have focused our structural attention on the N-terminal domain of LEDGF, a member of the PWWP family of proteins. This N-terminal domain has been hypothesized to bind to naked DNA but recent data suggests that it may may bind to other chromatin elements (Botbol et al., 2008). In particular, the resemblance between LEDGF's PWWP domain and proteins in the Tudor family suggested to us that it may bind methyl lysine residues on histone tails. We have expressed and purified several constructs encompassing this domain, and have used this domain for binding studies with both nucleosomes purified from chicken erythrocytes and modified peptides. Crystallization trials of LEDGF PWWP domain complexed with DNA and peptides are underway. Botbol, Y., Raghavendra, N.K., Rahman, S., Engelman, A., and Lavigne, M. (2008) Nucleic Acids Res. 36, 1237-1246. Cherepanov, P., Ambrosio, A.L.B., Rahman, S., Ellenberger, T., and Engelman, A. (2005) Proc. Natl. Acad. Sci. USA 102, 17308-17313. Ciuffi, A., et al. (2005) Nature Med. 11, 1287-1289. Llano, M., et al. (2006) Science 314, 461-464.