A lysine-rich region within fungal BAG domain-containing proteins mediates a novel association with ribosomes.
A lysine-rich region within fungal BAG domain-containing proteins mediates a novel association with ribosomes.
复制标题
含有真菌 BAG 结构域的蛋白质内富含赖氨酸的区域介导与核糖体的新关联。
DOI：
10.1128/ec.00146-12
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Morano,KevinA
中科院分区：
文献类型：
--
作者：
Verghese,Jacob;Morano,KevinA
Heat shock protein 70 (Hsp70) is a highly conserved molecular chaperone that assists in the folding of nascent chains and the repair of unfolded proteins through iterative cycles of ATP binding, hydrolysis, and nucleotide exchange tightly coupled to polypeptide binding and release. Cochaperones, including nucleotide exchange factors (NEFs), modulate the rate of ADP/ATP exchange and serve to recruit Hsp70 to distinct processes or locations. Among three nonrelated cytosolic NEFs in Saccharomyces cerevisiae, the Bag-1 homologSNL1is unique in being tethered to the endoplasmic reticulum (ER) membrane. We demonstrate here a novel physical association between Snl1 and the intact ribosome. This interaction is both independent of and concurrent with binding to Hsp70 and is not dependent on membrane localization. The ribosome binding site is identified as a short lysine-rich motif within the amino terminus of the Snl1 BAG domain distinct from the Hsp70 interaction region. Additionally, we demonstrate a ribosome association with the Candida albicans Snl1 homolog and localize this putative NEF to a perinuclear/ER membrane, suggesting functional conservation in fungal BAG domain-containing proteins. We therefore propose that the Snl1 family of NEFs serves a previously unknown role in fungal protein biogenesis based on the coincident recruitment of ribosomes and Hsp70 to the ER membrane.
