TY - JOUR
T1 - Cyclic AMP-Dependent Protein Kinase Regulates the Subcellular Localization of Snf1-Sip1 Protein Kinase
AU - Hedbacker, Kristina
AU - Townley, Robert
AU - Carlson, Marian
PY - 2004/3
Y1 - 2004/3
N2 - The Snf1/AMP-activated protein kinase family has diverse roles in cellular responses to metabolic stress. In Saccharomyces cerevisiae, Snf1 protein kinase has three isoforms of the β subunit that confer versatility on the kinase and that exhibit distinct patterns of subcellular localization. The Sip1 β subunit resides in the cytosol in glucose-grown cells and relocalizes to the vacuolar membrane in response to carbon stress. We show that translation of Sip1 initiates at the second ATG of the open reading frame, yielding a potential site for N myristoylation, and that mutation of the critical glycine abolishes relocalization. We further show that the cyclic AMP-dependent protein kinase (protein kinase A [PKA]) pathway maintains the cytoplasmic localization of Sip1 in glucose-grown cells. The Snf1 catalytic subunit also exhibits aberrant localization to the vacuolar membrane in PKA-deficient cells, indicating that PKA regulates the localization of Snf1-Sip1 protein kinase. These findings establish a novel mechanism of regulation of Snf1 protein kinase by the PKA pathway.
AB - The Snf1/AMP-activated protein kinase family has diverse roles in cellular responses to metabolic stress. In Saccharomyces cerevisiae, Snf1 protein kinase has three isoforms of the β subunit that confer versatility on the kinase and that exhibit distinct patterns of subcellular localization. The Sip1 β subunit resides in the cytosol in glucose-grown cells and relocalizes to the vacuolar membrane in response to carbon stress. We show that translation of Sip1 initiates at the second ATG of the open reading frame, yielding a potential site for N myristoylation, and that mutation of the critical glycine abolishes relocalization. We further show that the cyclic AMP-dependent protein kinase (protein kinase A [PKA]) pathway maintains the cytoplasmic localization of Sip1 in glucose-grown cells. The Snf1 catalytic subunit also exhibits aberrant localization to the vacuolar membrane in PKA-deficient cells, indicating that PKA regulates the localization of Snf1-Sip1 protein kinase. These findings establish a novel mechanism of regulation of Snf1 protein kinase by the PKA pathway.
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U2 - 10.1128/MCB.24.5.1836-1843.2004
DO - 10.1128/MCB.24.5.1836-1843.2004
M3 - Article
C2 - 14966266
AN - SCOPUS:1342282918
SN - 0270-7306
VL - 24
SP - 1836
EP - 1843
JO - Molecular and cellular biology
JF - Molecular and cellular biology
IS - 5
ER -