Takahashi Masaki, Mizuguchi Mineyuki, Shinoda Hiroyuki, Aizawa Tomoyasu, Demura Makoto, Okazawa Hitoshi, Kawano Keiichi
Faculty of Pharmaceutical Sciences, University of Toyama, 2630, Sugitani, Toyama 930-0194, Japan.
Biochim Biophys Acta. 2010 Jul;1804(7):1500-7. doi: 10.1016/j.bbapap.2010.03.007. Epub 2010 Mar 20.
Polyglutamine tract-binding protein-1 (PQBP-1) is a nuclear protein that interacts with various proteins, including RNA polymerase II and the spliceosomal protein U5-15kD. PQBP-1 is known to be associated with X-linked mental retardation in which a frameshift mutation in the PQBP-1 gene occurs. In the present study, we demonstrate that PQBP-1 binds to U5-15kD via a continuous 23-residue segment within its C-terminal domain. Intriguingly, this segment is lost in the frameshift mutants of PQBP-1 associated with X-linked mental retardation. These findings suggest that the frameshift mutations in the PQBP-1 gene lead to expression of mutants lacking the ability to interact with U5-15kD.
聚谷氨酰胺链结合蛋白1（PQBP-1）是一种核蛋白，它能与多种蛋白质相互作用，包括RNA聚合酶II和剪接体蛋白U5-15kD。已知PQBP-1与X连锁智力迟钝有关，其中PQBP-1基因会发生移码突变。在本研究中，我们证明PQBP-1通过其C末端结构域内一个连续的23个残基的片段与U5-15kD结合。有趣的是，在与X连锁智力迟钝相关的PQBP-1移码突变体中，这个片段缺失了。这些发现表明，PQBP-1基因中的移码突变导致了缺乏与U5-15kD相互作用能力的突变体的表达。
