High impact information on VCX1

• After this release, low cytosolic Ca(2+) is restored and vacuolar Ca(2+) is replenished through the activity of Vcx1p, a Ca(2+)/H(+) exchanger [1].
• Also, the Ca2+ content of hum1 pmc1 cells is less than that of pmc1 cells [2].
• In contrast, the Ca2+ sensitivity of vph1 mutants, which are specifically defective in vacuolar acidification, is not significantly altered by disruption of Hum1p function [2].
• The Ca2+ sensitivity of pmc1 mutants, which lack a P-type ATPase presumed to transport Ca2+ into the vacuole, is exacerbated in a hum1 mutant strain background [2].
• Vacuolar membrane vesicles from hum1 mutants lack all Ca2+/H+ antiport activity, demonstrating that Hum1p catalyzes the exchange of Ca2+ for H+ across the yeast vacuolar membrane [2].

Biological context of VCX1

• We investigated the effect of disrupting HUM1 in other strains with defects in Ca2+ homeostasis [2].

Associations of VCX1 with chemical compounds

• Using a yeast growth assay, a mutant allele of VCX1 (VCX1-S204A/L208P), termed VCX1-M1, was previously found to confer strong Mn(2+) tolerance [3].
• A single nucleotide change in the MNR1 (VCX1/HUM1) gene determines resistance to manganese in Saccharomyces cerevisiae [4].

Other interactions of VCX1

• In a genetic screen for yeast manganese-resistance mutants, we identified S. cerevisiae MAM3 as a gene which, when deleted, would increase cellular tolerance to toxic levels of manganese and also increased the cell's resistance towards cobalt and zinc [5].

References