The prefoldin‐like protein AtURI exhibits characteristics of intrinsically disordered proteins

Abstract

The prefoldin‐like protein UNCONVENTIONAL PREFOLDIN RPB5 INTERACTOR (URI) participates in diverse cellular functions, including protein homeostasis, transcription, translation, and signal transduction. Thus, URI is a highly versatile protein, although the molecular basis of this versatility remains unknown. In this work, we show that Arabidopsis thaliana (Arabidopsis) URI (AtURI) possesses a large intrinsically disordered region (IDR) spanning most of the C‐terminal part of the protein, a feature conserved in yeast and human orthologs. Our findings reveal two key characteristics of disordered proteins in AtURI: promiscuity in interacting with partners and protein instability. We propose that these two features contribute to providing AtURI with functional versatility.

Prefoldin Subunits and Its Associate Partners: Conservations and Specificities in Plants

“…Very recent studies in Arabidopsis indicates the existence of PFDL subunits in plants [ 26 , 32 ]. Arabidopsis URI ortholog was firstly identified by forward genetic screening with altered auxin distribution [ 32 ].…”

“…Arabidopsis URI ortholog was firstly identified by forward genetic screening with altered auxin distribution [ 32 ]. Further analysis demonstrated that URI was the PFDL subunits and showed conserved roles in Arabidopsis [ 26 , 32 ]. Moreover, putative ortholog analysis identified PDRG1 , UXT , and ASDURF genes ( Table 1 ), and AP-MS assay demonstrated URI, PFD2, PFD6, PDRG1, and ASDURF as interactors of UXT [ 26 ].…”

“…Further analysis demonstrated that URI was the PFDL subunits and showed conserved roles in Arabidopsis [ 26 , 32 ]. Moreover, putative ortholog analysis identified PDRG1 , UXT , and ASDURF genes ( Table 1 ), and AP-MS assay demonstrated URI, PFD2, PFD6, PDRG1, and ASDURF as interactors of UXT [ 26 ]. The interactions between URI and PFD2/PFD6 were also verified by yeast-two-hybrid assay and co-immunoprecipitate assay [ 32 ].…”

“…In addition to the classic prefoldin subunits, there are also PFDL members exist in eukaryotes kingdom. Human and plant PFDL subunits include URI, UXT, PDRG1, and ASDURF [ 26 , 36 ], while Bud27 (URI homologue) is the exclusive PFDL in yeast [ 38 ]. Here, we put plant URI as the paradigm and summarize the conservations and specificities compared with that in animals.…”

“…Unlike typical PFDc, the PFDLc has the additional ability to participate in RNA polymerases assembly [ 21 , 22 ], to stabilize phosphatidylinositol-3 kinase-associated protein kinases [ 23 ], and to inhibit certain cytoplasmic enzymes [ 24 ], and may also provide a platform for the stabilization and maturation of intracellular multiprotein complexes [ 25 ]. A very recent study demonstrated the existence of PFDLc in Arabidopsis thaliana (Arabidopsis) [ 26 ], indicating the conserved process in species evolution.…”