The Cytosolic Chaperonin CCT/TRiC and Cancer Cell Proliferation
نویسندگان
چکیده
The molecular chaperone CCT/TRiC plays a central role in maintaining cellular proteostasis as it mediates the folding of the major cytoskeletal proteins tubulins and actins. CCT/TRiC is also involved in the oncoprotein cyclin E, the Von Hippel-Lindau tumour suppressor protein, cyclin B and p21(ras) folding which strongly suggests that it is involved in cell proliferation and tumor genesis. To assess the involvement of CCT/TRiC in tumor genesis, we quantified its expression levels and activity in 18 cancer, one non-cancer human cell lines and a non-cancer human liver. We show that the expression levels of CCT/TRiC in cancer cell lines are higher than that in normal cells. However, CCT/TRiC activity does not always correlate with its expression levels. We therefore documented the expression levels of CCT/TRiC modulators and partners PhLP3, Hop/P60, prefoldin and Hsc/Hsp70. Our analysis reveals a functional interplay between molecular chaperones that might account for a precise modulation of CCT/TRiC activity in cell proliferation through changes in the cellular levels of prefoldin and/or Hsc/p70 and CCT/TRiC client protein availability. Our observation and approaches bring novel insights in the role of CCT/TRiC-mediated protein folding machinery in cancer cell development.
منابع مشابه
Protein folding: Versatility of the cytosolic chaperonin TRiC/CCT
Efficient de novo folding of actins and tubulins requires two molecular chaperones, the chaperonin TRiC (or CCT) and its novel cofactor GimC (or prefoldin). Recent studies indicate that TRiC is exquisitely adapted for this task, yet has the ability to interact with and assist the folding of numerous other cellular proteins.
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