Unveiling the Role of Sorghum RPAP3 in the Function of R2TP Complex: Insights into Protein Assembly in Plants.

Antonio LM, Martins GH, Aragão AZB, Quel NG, Zazeri G, Houry WA, Ramos CHI

Published: 26 August 2023 in Plants (Basel, Switzerland)
Keywords: R2TP, RPAP3, Sorghum, molecular chaperone, protein complex assembly
Pubmed ID: 37631136
DOI: 10.3390/plants12162925

The chaperone R2TP has multiple subunits that assist in the proper folding, assembly, and stabilization of various protein complexes in cells and its study can offer valuable insights into the regulation and maintenance of protein assemblies in plant systems. The 'T' component of R2TP is Tah1 in yeast, consisting of 111 residues, while its counterpart in humans is RPAP3, with 665 residues. RPAP3 acts as a co-chaperone of Hsp90 and facilitates interactions between RUVBL proteins and other complex components, enhancing the recruitment of client proteins by the R2TP complex. These facts further underscore the relevance of studying this complex in different organisms. The putative gene corresponding to the RPAP3 in Sorghum bicolor, a monocotyledon plant, was cloned, and the protein (396 residues) purified for biochemical characterization. SbRPAP3 exists as a folded monomer and has a RPAP3 domain, which is present in human RPAP3 but absent in yeast Tah1. SbRPAP3 retains its functional capabilities, including binding with RUVBLs, Hsp90, and Hsp70. By elucidating the role of RPAP3 in plant R2TP complex, we can further comprehend the molecular mechanisms underlying plant-specific protein assembly and contribute to advancements in plant biology and biotechnological applications.

Brazilian National Council for Scientific and Technological Development (CNPq) 117092/2019-3
Brazilian National Council for Scientific and Technological Development (CNPq) 141709/2021-9
Brazilian National Council for Scientific and Technological Development (CNPq) 305148/2019-2
Canadian Institutes of Health Research (CIHR) PJT-173491
Global Affairs Canada no grant ID listed
The São Paulo Research Foundation, FAPESP 2012/50161-8
The São Paulo Research Foundation, FAPESP 2017/26131-5
The São Paulo Research Foundation, FAPESP 2022/01955-3
The São Paulo Research Foundation, FAPESP 2022/08855-4
The São Paulo Research Foundation, FAPESP - Coordination for the Improvement of Higher Education Personnel (CAPES) 99999.004913/2015-09