TY - JOUR
T1 - Functional analysis of proposed substrate-binding residues of Hsp104
AU - Howard, Matthew K.
AU - Sohn, Brian S.
AU - von Borcke, Julius
AU - Xu, Andy
AU - Jackrel, Meredith E.
N1 - Funding Information:
This work was funded by the Frick Foundation for ALS Research, the ALS Association 20IIA529, Target ALS, and NIH R35GM128772 to MEJ. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. We thank members of the Jackrel Lab for insightful comments.
Publisher Copyright:
© 2020 Howard et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
PY - 2020
Y1 - 2020
N2 - Hsp104 is a hexameric AAA+ yeast disaggregase capable of solubilizing disordered aggregates and amyloid. Hsp104 couples ATP hydrolysis to polypeptide translocation through its central channel. Substrate binding by Hsp104 is mediated primarily by two conserved tyrosine residues in nucleotide binding domain (NBD) 1 and NBD2. Recent structural studies have revealed that an additional tyrosine residue (Y650) located in NBD2 appears to contact substrate and may play an important role in Hsp104 function. Here, we functionally analyze the properties of this proposed Hsp104 –substrate interaction. We find that Y650 is not essential for Hsp104 to confer thermotolerance. Supporting these findings, in a potentiated Hsp104 variant background, the Y650A mutation does not abolish potentiation. However, modulation of this site does have subtle effects on the activity of this potentiated Hsp104 variant. We therefore suggest that while Y650 is not essential for Hsp104 function, its modulation may be useful for fine-tuning Hsp104 properties.
AB - Hsp104 is a hexameric AAA+ yeast disaggregase capable of solubilizing disordered aggregates and amyloid. Hsp104 couples ATP hydrolysis to polypeptide translocation through its central channel. Substrate binding by Hsp104 is mediated primarily by two conserved tyrosine residues in nucleotide binding domain (NBD) 1 and NBD2. Recent structural studies have revealed that an additional tyrosine residue (Y650) located in NBD2 appears to contact substrate and may play an important role in Hsp104 function. Here, we functionally analyze the properties of this proposed Hsp104 –substrate interaction. We find that Y650 is not essential for Hsp104 to confer thermotolerance. Supporting these findings, in a potentiated Hsp104 variant background, the Y650A mutation does not abolish potentiation. However, modulation of this site does have subtle effects on the activity of this potentiated Hsp104 variant. We therefore suggest that while Y650 is not essential for Hsp104 function, its modulation may be useful for fine-tuning Hsp104 properties.
UR - https://www.scopus.com/pages/publications/85081215645
U2 - 10.1371/journal.pone.0230198
DO - 10.1371/journal.pone.0230198
M3 - Article
C2 - 32155221
AN - SCOPUS:85081215645
SN - 1932-6203
VL - 15
JO - PloS one
JF - PloS one
IS - 3
M1 - e0230198
ER -