Sugashima Marine Biological Laboratory, Graduate School of Science, Nagoya University, Sugashima, Toba 517-0004, Japan.
Biochem Biophys Res Commun. 2011 Jul 15;410(4):809-15. doi: 10.1016/j.bbrc.2011.06.069. Epub 2011 Jun 15.
We previously reported that the ascidian sperm proteasome degrades the egg-coat protein extracellularly during fertilization. In order to explore an extracellular transport signal, we purified the proteasome from ascidian sperm and compared its subunit structure with egg and muscle proteasomes. The results showed that PSMA1/α6 subunit of the sperm proteasome is distinct from egg and muscle proteasomes. LC/MS/MS analysis revealed that the C-terminal 16 residues of sperm α6 subunit are processed. Whereas sperm-specific paralogous genes of α subunits are reported, its sperm-specific C-terminal processing is a newly discovered novel post-translational modification of the proteasome.
我们之前报道过海鞘精子中的蛋白酶体在受精过程中降解卵壳蛋白。为了探索细胞外转运信号，我们从海鞘精子中纯化了蛋白酶体，并比较了其亚基结构与卵和肌肉蛋白酶体的差异。结果表明，精子蛋白酶体的 PSMA1/α6 亚基与卵和肌肉蛋白酶体不同。LC/MS/MS 分析显示，精子α6 亚基的 C 端 16 个残基被加工。虽然已经报道了α 亚基的精子特异性同源基因，但它的精子特异性 C 端加工是蛋白酶体的一种新发现的新型翻译后修饰。
