Nutrients, via the Tor proteins, stimulate the association of Tap42 with type 2A phosphatases.
We identified an essential Saccharomyces cerevisiae protein, Tap42, that associates with Sit4, a type 2A-related protein phosphatase, and with the type 2A phosphatase catalytic subunits. The association of Tap42 with the phosphatases does not require the previously identified phosphatase subunits. Genetic analysis suggests that Tap42 functions positively with both phosphatases. Mutations in TAP42 can confer almost complete rapamycin resistance. In addition, Tap42/Sit4 and Tap42/PP2A complex formation is regulated by nutrient growth signals and the rapamycin-sensitive Tor signaling pathway. These findings, combined with the defect in translation of the tap42-11 mutant at the nonpermissive temperature, suggest that Tap42, Sit4, and PP2A are components of the Tor signaling pathway.
Di Como
C J
CJ
Cold Spring Harbor Laboratory, New York 11724, USA.
Arndt
K T
KT
D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D018797:Cell Cycle Proteins / Q000378:metabolism; D011232:Chemical Precipitation; D003470:Culture Media; D004352:Drug Resistance, Microbial / Q000235:genetics; D005656:Fungal Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D016153:Genes, Suppressor; D008969:Molecular Sequence Data; D009154:Mutation; D019869:Phosphatidylinositol 3-Kinases; D010749:Phosphoprotein Phosphatases / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D010750:Phosphoproteins / Q000737:chemistry; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D011090:Polyenes / Q000494:pharmacology; D054648:Protein Phosphatase 2; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000187:drug effects / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D020123:Sirolimus
D048868:Adaptor Proteins, Signal Transducing; D018797:Cell Cycle Proteins; D003470:Culture Media; D005656:Fungal Proteins; D019869:Phosphatidylinositol 3-Kinases; D010749:Phosphoprotein Phosphatases; D010750:Phosphoproteins; D017853:Phosphotransferases (Alcohol Group Acceptor); D011090:Polyenes; D054648:Protein Phosphatase 2; D029701:Saccharomyces cerevisiae Proteins; D020123:Sirolimus; C071246:CDC55 protein, S cerevisiae; C100984:TAP42 protein, S cerevisiae; C083324:TOR1 protein, S cerevisiae; C081135:TOR2 protein, S cerevisiae; C104343:SIT4 protein, S cerevisiae