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The SAP, a New Family of Proteins, Associate and Function Positively with the SIT4 Phosphatase

Overview
Journal Mol Cell Biol
Specialty Cell Biology
Date 1996 Jun 1
PMID 8649382
Citations 82
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Abstract

SIT4 is the catalytic subunit of a type 2A-related protein phosphatase in Saccharomyces cerevisiae that is required for G1 cyclin transcription and for bud formation. SIT4 associates with several high-molecular-mass proteins in a cell cycle-dependent fashion. We purified two SIT4-associated proteins, SAP155 and SAP190, and cloned the corresponding genes. By sequence homology, we isolated two additional SAP genes, SAP185 and SAP4. Through such an association is not yet proven for SAP4, each of SAP155, SAP185, and SAP190 physically associates with SIT4 in separate complexes. The SAPs function positively with SIT4, and by several criteria, the loss of all four SAPs is equivalent to the loss of SIT4. The data suggest that the SAPs are not functional in the absence of SIT4 and likewise that SIT4 is not functional in the absence of the SAPs. The SAPs are hyperphoshorylated in cells lacking SIT4, raising the possibility that the SAPs are substrates of SIT4. By sequence similarity, the SAPs fall into two groups, the SAP4/SAP155 group and the SAP185/SAP190 group. Overexpression of a SAP from one group does not suppress the defects due to the loss of the other group. These findings and others indicate that the SAPs have distinct functions.

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References
1.
Kim Y, Francisco L, Chen G, Marcotte E, Chan C . Control of cellular morphogenesis by the Ip12/Bem2 GTPase-activating protein: possible role of protein phosphorylation. J Cell Biol. 1994; 127(5):1381-94. PMC: 2120258. DOI: 10.1083/jcb.127.5.1381. View

2.
Miosga T, Boles E, Schmitt S, ZIMMERMANN F . Sequence and function analysis of a 9.74 kb fragment of Saccharomyces cerevisiae chromosome X including the BCK1 gene. Yeast. 1994; 10(11):1481-8. DOI: 10.1002/yea.320101112. View

3.
Di Como C, Bose R, Arndt K . Overexpression of SIS2, which contains an extremely acidic region, increases the expression of SWI4, CLN1 and CLN2 in sit4 mutants. Genetics. 1995; 139(1):95-107. PMC: 1206351. DOI: 10.1093/genetics/139.1.95. View

4.
Collins K, Kobayashi R, Greider C . Purification of Tetrahymena telomerase and cloning of genes encoding the two protein components of the enzyme. Cell. 1995; 81(5):677-86. DOI: 10.1016/0092-8674(95)90529-4. View

5.
Lin F, Arndt K . The role of Saccharomyces cerevisiae type 2A phosphatase in the actin cytoskeleton and in entry into mitosis. EMBO J. 1995; 14(12):2745-59. PMC: 398393. DOI: 10.1002/j.1460-2075.1995.tb07275.x. View