The eukaryotic cytosolic chaperonin containing TCP-1 (CCT) has an important 
function in maintaining cellular homoeostasis by assisting the folding of many 
proteins, including the cytoskeletal components actin and tubulin. Yet the 
nature of the proteins and cellular pathways dependent on CCT function has not 
been established globally. Here, we use proteomic and genomic approaches to 
define CCT interaction networks involving 136 proteins/genes that include links 
to the nuclear pore complex, chromatin remodelling, and protein degradation. Our 
study also identifies a third eukaryotic cytoskeletal system connected with CCT: 
the septin ring complex, which is essential for cytokinesis. CCT interactions 
with septins are ATP dependent, and disrupting the function of the chaperonin in 
yeast leads to loss of CCT-septin interaction and aberrant septin ring assembly. 
Our results therefore provide a rich framework for understanding the function of 
CCT in several essential cellular processes, including epigenetics and cell 
division.