ISOLATION AND CHARACTERIZATION OF THE CANDIDA-ALBICANS SEC4 GENE

The SEC4 gene product is a major component of the protein secretion ma chinery. More specifically, it is believed to play a pivotal role in t argeting and fusion of secretory vesicles to the plasma membrane. Its recently described implication with the Saccharomyces cerevisiae Rho3p , which is required for directing growing points during bud formation, has prompted us to investigate the role and function of Sec4p in the morphological changes of the yeast pathogen Candida albicans. We have therefore cloned the C. albicans SEC4 gene. It encodes a 210 amino aci ds long protein sharing up to 75% homology to the S. cerevisiae homolo g, when conserved changes are allowed. Its RNA is constitutively expre ssed in C. albicans grown under various physiological conditions. We a lso show that it can functionally complement a S. cerevisiae sec4 ther mosensitive mutant. The sequence of the C. albicans SEC4 gene has been deposited in GenBank under Accession Number AF017183. (C) 1998 John W iley & Sons, Ltd.