Mansure José João, Furtado Daniel Rodrigues, de Oliveira Francisco Meirelles Bastos, Rumjanek Franklin David, Franco Glória Regina, Fantappié Marcelo Rosado
Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Ilha do Fundão, Rio de Janeiro 21941-590, Brazil.
Biochem Biophys Res Commun. 2005 Oct 7;335(4):1163-72. doi: 10.1016/j.bbrc.2005.07.192.
The most studied arginine methyltransferase is the type I enzyme, which catalyzes the transfer of an S-adenosyl-L-methionine to a broad spectrum of substrates, including histones, RNA-transporting proteins, and nuclear hormone receptor coactivators. We cloned a cDNA encoding a protein arginine methyltransferase in Schistosoma mansoni (SmPRMT1). SmPRMT1 is highly homologous to the vertebrate PRMT1 enzyme. In vitro methylation assays showed that SmPRMT1 recombinant protein was able to specifically methylate histone H4. Two schistosome proteins likely to be involved in RNA metabolism, SMYB1 and SmSmD3, that display a number of RGG motifs, were strongly methylated by SmPRMT1. In vitro GST pull-down assays showed that SMYB1 and SmSmD3 physically interacted with SmPRMT1. Additional GST pull-down assay suggested the occurrence of a ternary complex including SmPRMT1, SmRXR1 nuclear receptor, and the p160 (SRC-1) nuclear receptor coactivator. Together, these data suggest a mechanism by which SmPRMT1 plays a role in nuclear receptor-mediated chromatin remodeling and RNA transactions.
研究最多的精氨酸甲基转移酶是I型酶，它催化S-腺苷-L-甲硫氨酸转移到多种底物上，包括组蛋白、RNA转运蛋白和核激素受体共激活因子。我们克隆了曼氏血吸虫中一种编码蛋白质精氨酸甲基转移酶的cDNA（SmPRMT1）。SmPRMT1与脊椎动物的PRMT1酶高度同源。体外甲基化分析表明，SmPRMT1重组蛋白能够特异性地甲基化组蛋白H4。两种可能参与RNA代谢的血吸虫蛋白SMYB1和SmSmD3，具有多个RGG基序，被SmPRMT1强烈甲基化。体外GST下拉分析表明，SMYB1和SmSmD3与SmPRMT1发生物理相互作用。额外的GST下拉分析表明存在一种三元复合物，包括SmPRMT1、SmRXR1核受体和p160（SRC-1）核受体共激活因子。这些数据共同提示了一种机制，通过该机制SmPRMT1在核受体介导的染色质重塑和RNA事务中发挥作用。
