PT  - JOURNAL ARTICLE
AU  - Paidhungat, Madan
AU  - Garrett, Stephen
TI  - Cdc1 and the Vacuole Coordinately Regulate Mn<sup>2+</sup> Homeostasis in the Yeast <em>Saccharomyces cerevisiae</em>
DP  - 1998 Apr 01
TA  - Genetics
PG  - 1787--1798
VI  - 148
IP  - 4
4099  - http://www.genetics.org/content/148/4/1787.short
4100  - http://www.genetics.org/content/148/4/1787.full
SO  - Genetics1998 Apr 01; 148
AB  - The yeast CDC1 gene encodes an essential protein that has been implicated in the regulation of cytosolic [Mn2+]. To identify factors that impinge upon Cdc1 or the Cdc1-dependent process, we isolated secondsite suppressors of the conditional cdc1-1(Ts) growth defect. Recessive suppressors define 15 COS (CdcOne Suppressor) genes. Seven of the fifteen COS genes are required for biogenesis of the vacuole, an organelle known to sequester intracellular Mn2+. An eighth gene, COS16, encodes a vacuolar membrane protein that seems to be involved in Mn2+ homeostasis. These results suggest mutations that block vacuolar Mn2+ sequestration compensate for defects in Cdc1 function. Interestingly, Cdc1 is dispensable in a cos16Δ deletion strain, and a cdc1Δ cos16Δ double mutant exhibits robust growth on medium supplemented with Mn2+. Thus, the single, essential function of Cdc1 is to regulate intracellular, probably cytosolic, Mn2+.