CLC1

Abstract In most strain backgrounds, haploid yeast cells lacking 93% of the CLC1 coding region are viable, but grow -2-3 times more slowly than wild-type cells. Upon propagation, fastergrowing variants arise. Cells lacking both clathrin light chain and clathrin heavy chain (encoded by CHC1 - see CHC1 entry p. 267) are also viable but slow-growing. Clathrin heavy chain is less stable in c/c1 cells than in wildtype cells4. Vesicles isolated from clc1 cells do not contain detectable clathrin heavy chain, even if prepared from cells overproducing clathrin heavy chain5 It has not been determined whether clathrin heavy chain coats on these vesicles are unstable to isolation or whether they are never formed. Light-chain-deficient cells, like cells lacking clathrin heavy chain6, secrete a heterogeneous high molecular weight form of the mating pheromone a-factor4, presumably due to the mislocalization of the processing protease Kex2p.