Cell surface mannan is implicated in almost every aspect of pathogenicity of @entity5132 . In @entity375 , the @entity33254 protein acts as a master regulator of mannan synthesis through its role in substrate provision. The substrate for mannosylation of proteins and lipids in the Golgi apparatus is @entity3006 - @entity3913 , whose lumenal transport is catalyzed by @entity33254 . This @entity20561 is synthesized in the cytoplasm by pathways that are highly conserved in all eukaryotes, but its lumenal transport (and hence Golgi apparatus-specific mannosylation) is a fungus-specific process. To begin to study the role of Golgi mannosylation in @entity5132 , we isolated the CaVRG4 gene and analyzed the effects of loss of its function. CaVRG4 encodes a functional homologue of the @entity375 @entity3006 - @entity3913 transporter. CaVrg4p localized to punctate spots within the cytoplasm of @entity5132 in a pattern reminiscent of localization of @entity33254 in the Golgi apparatus in @entity375 . Like partial loss of ScVRG4 function, partial loss of CaVRG4 function resulted in mannosylation defects, which in turn led to a number of cell wall-associated phenotypes. While heterozygotes displayed no growth phenotypes, a hemizygous strain, containing a single copy of CaVRG4 under control of the @entity1853 -repressible @entity40390 promoter, did not grow in the presence of @entity1853 and @entity462 , demonstrating that CaVRG4 is essential for viability. Mutant Candida @entity33254 strains were defective in hyphal formation but exhibited a constitutive polarized mode of pseudohyphal growth. Because the @entity33254 gene is essential for @entity375 viability but does not have a @entity1 homologue, it is a particularly attractive target for development of antifungal therapies.

Molecular and phenotypic analysis of CaVRG4, encoding an essential Golgi apparatus XXXX - @entity3913 transporter.

@entity1 :: ('9606', 'Species') :: ['mammalian'] @entity462 :: ('MESH:D003545', 'Chemical') :: ['cysteine'] @entity40390 :: ('853466(Tax:4932)', 'Gene') :: ['MET3'] @entity1853 :: ('MESH:D008715', 'Chemical') :: ['methionine'] @entity5132 :: ('5476', 'Species') :: ['Candida albicans', 'C. albicans'] @entity3006 :: ('MESH:D006153', 'Chemical') :: ['GDP'] @entity3913 :: ('MESH:D008358', 'Chemical') :: ['mannose'] @entity20561 :: ('CHEBI:25609', 'Chemical') :: ['nucleotide sugar'] @entity33254 :: ('852647(Tax:4932)', 'Gene') :: ['vrg4', 'Vrg4p', 'Vrg4', 'VRG4'] @entity375 :: ('4932', 'Species') :: ['S. cerevisiae', 'yeast', 'Saccharomyces cerevisiae']
@entity3006 :: (MESH:D006153,Chemical) :: ['GDP']
