Mak Wai Shun, Tsang Tsz Ming, Chan Tsz Yin, Lukov Georgi L
Faculty of Sciences, Brigham Young University-Hawaii, Laie, HI 96762, USA.
Genome Center, University of California Davis, Davis, CA 95616, USA.
Proteomes. 2021 Oct 2;9(4):40. doi: 10.3390/proteomes9040040.
This study investigates whether selected WD40 proteins with a 7-bladed β-propeller structure, similar to that of the β subunit of the G protein heterotrimer, interact with the cytosolic chaperonin CCT and its known binding partner, PhLP1. Previous studies have shown that CCT is required for the folding of the Gβ subunit and other WD40 proteins. The role of PhLP1 in the folding of Gβ has also been established, but it is unknown if PhLP1 assists in the folding of other Gβ-like proteins. The binding of three Gβ-like proteins, TBL2, MLST8 and CDC20, to CCT and PhLP1, was demonstrated in this study. Co-immunoprecipitation assays identified one novel binding partner for CCT and three new interactors for PhLP1. All three of the studied proteins interact with CCT and PhLP1, suggesting that these proteins may have a folding machinery in common with that of Gβ and that the well-established Gβ folding mechanism may have significantly broader biological implications than previously thought. These findings contribute to continuous efforts to determine common traits and unique differences in the folding mechanism of the WD40 β-propeller protein family, and the role PhLP1 has in this process.
本研究调查了某些具有七叶β-螺旋桨结构的WD40蛋白（类似于G蛋白异源三聚体的β亚基）是否与胞质伴侣蛋白CCT及其已知结合伴侣PhLP1相互作用。先前的研究表明，CCT是Gβ亚基和其他WD40蛋白折叠所必需的。PhLP1在Gβ折叠中的作用也已确定，但尚不清楚PhLP1是否协助其他Gβ样蛋白的折叠。本研究证实了三种Gβ样蛋白TBL2、MLST8和CDC20与CCT和PhLP1的结合。免疫共沉淀试验确定了CCT的一个新结合伴侣和PhLP1的三个新相互作用分子。所有三种研究蛋白均与CCT和PhLP1相互作用，这表明这些蛋白可能与Gβ具有共同的折叠机制，且成熟的Gβ折叠机制可能具有比之前认为的更广泛的生物学意义。这些发现有助于持续努力确定WD40β-螺旋桨蛋白家族折叠机制中的共同特征和独特差异，以及PhLP1在此过程中的作用。
