Hsl7 is a substrate-specific type II protein arginine methyltransferase in yeast
Hsl7 is a substrate-specific type II protein arginine methyltransferase in yeast
复制标题
DOI：
10.1016/j.bbrc.2008.05.121
复制
发表时间：
2008-08-08
影响因子：
3.1
通讯作者：
Clarke, Steven G.
中科院分区：
文献类型：
--
作者：
Sayegh, Joyce;Clarke, Steven G.
酿酒酵母蛋白Hsl 7是细胞周期检查点控制中的Swe 1蛋白激酶的调节剂。Hsl 7先前已被描述为III型蛋白质精氨酸甲基转移酶，催化在非生理底物上形成ω-单甲基精氨酸残基。然而，我们在这里表明，Hsl 7也可以显示11型活性，产生对称的二甲基精氨酸残基小牛胸腺组蛋白H2 A。对称二甲基化仅在酶和甲基接受底物孵育延长时间时观察到。我们通过氨基酸分析和薄层色谱法用从细菌和酵母表达的野生型和突变体重组酶证实了Hsl 7依赖的对称二甲基精氨酸的形成。这一结果是有意义的，因为以前在S.啤酒。我们还表明，Hsl 7对GST-GAR（蛋白质精氨酸甲基转移酶的常用底物）几乎没有活性或没有活性，并且对髓鞘碱性蛋白只有最小的活性。因此，这种酶可能只识别酵母中的一小部分潜在底物蛋白，与主要的I型甲基转移酶Rmt 1的情况相反。(c)2008年爱思唯尔公司All rights reserved.
The Saccharomyces cerevisiae protein Hsl7 is a regulator of the Swe1 protein kinase in cell cycle checkpoint control. Hsl7 has been previously described as a type III protein arginine methyl transferase, catalyzing the formation of omega-monomethylarginine residues on non-physiological substrates. However, we show here that Hsl7 can also display type 11 activity, generating symmetric dimethylarginine residues on calf thymus histone H2A. Symmetric dimethylation is only observed when enzyme and the methyl-accepting substrate were incubated for extended times. We confirmed the Hsl7-dependent formation of symmetric dimethylarginine by amino acid analysis and thin layer chromatography with wild-type and mutant recombinant enzymes expressed from both bacteria and yeast. This result is significant because no type II activity has been previously demonstrated in S. cerevisiae. We also show that Hsl7 has little or no activity on GST-GAR, a commonly used substrate for protein arginine methyltransferases, and only minimal activity on myelin basic protein. This enzyme thus may only recognize only a small subset of potential substrate proteins in yeast, in contrast to the situation with Rmt1, the major type I methyltransferase. (c) 2008 Elsevier Inc. All rights reserved.