Tessarz Peter, Schwarz Michael, Mogk Axel, Bukau Bernd
Universität Heidelberg, Zentrum fuer Molekulare Biologie Heidelberg, DKFZ-ZMBH Alliance, Im Neuenheimer Feld 282, Heidelberg D-69120, Germany.
Mol Cell Biol. 2009 Jul;29(13):3738-45. doi: 10.1128/MCB.00201-09. Epub 2009 Apr 27.
The yeast AAA(+) chaperone Hsp104 is essential for the development of thermotolerance and for the inheritance of prions. Recently, Hsp104, together with the actin cytoskeleton, has been implicated in the asymmetric distribution of carbonylated proteins. Here, we investigated the interplay between Hsp104 and actin by using a dominant-negative variant of Hsp104 (HAP/ClpP) that degrades substrate proteins instead of remodeling them. Coexpression of HAP/ClpP causes defects in morphology and the actin cytoskeleton. Taking a candidate approach, we identified Spa2, a member of the polarisome complex, as an Hsp104 substrate. Furthermore, we provided genetic evidence that links Spa2 and Hsp104 to Hof1, a member of the cytokinesis machinery. Spa2 and Hof1 knockout cells are affected in the asymmetric distribution of damaged proteins, suggesting that Hsp104, Spa2, and Hof1 are members of a network controlling the inheritance of carbonylated proteins.
酵母AAA(+)伴侣蛋白Hsp104对于耐热性的形成和朊病毒的遗传至关重要。最近，Hsp104与肌动蛋白细胞骨架一起，参与了羰基化蛋白质的不对称分布。在这里，我们通过使用Hsp104的显性负变体（HAP/ClpP）来研究Hsp104与肌动蛋白之间的相互作用，该变体降解底物蛋白而不是对其进行重塑。HAP/ClpP的共表达导致形态和肌动蛋白细胞骨架出现缺陷。通过候选方法，我们鉴定出极性体复合物的成员Spa2是Hsp104的底物。此外，我们提供了遗传证据，将Spa2和Hsp104与胞质分裂机制的成员Hof1联系起来。Spa2和Hof1基因敲除细胞在受损蛋白质的不对称分布中受到影响，这表明Hsp104、Spa2和Hof1是控制羰基化蛋白质遗传的网络成员。
