Protein
Serine/threonine-protein kinase YPK1
Organism
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Function
Plays an essential role in the proliferation of yeast cells. Involved in a signaling pathway, required for optimal cell wall integrity, that acts in parallel with the PKC1-SLT2-dependent pathway. Downstream kinase in the sphingolipid-mediated signaling pathway. Its phosphorylation is regulated by the intracellular sphingolipid concentration. Cooperates with SLI1 in mediating resistance to the sphingolipid biosynthesis inhibitor drug myriocin (ISP-1). Its kinase activity is essential for the resistance. Required for both receptor-mediated and fluid-phase endocytosis, but is not necessary for receptor phosphorylation or ubiquitination. Necessary for the internalization of plasma membrane proteins carrying different types of internalization signals. Acts downstream of the PKH kinases to control endocytosis by phosphorylating components of the endocytic machinery. Phosphorylation of residue Thr-504 in the activation loop is essential for activity. phosphorylates and down-regulates flippase activator FPK1.
Similarity
Belongs to the protein kinase superfamily. AGC Ser/Thr protein kinase family. RAC subfamily.
Sequence
MYSWKSKFKFGKSKEEKEAKHSGFFHSSKKEEQQNNQATAGEHDASITRSSLDRKGTINPSNSSVVPVRVSYDASSSTSTVRDSNGGNSENTNSSQNLDETANIGSTGTPNDATSSSGMMTIKVYNGDDFILPFPITSSEQILNKLLASGVPPPHKEISKEVDALIAQLSRVQIKNQGPADEDLISSESAAKFIPSTIMLPGSSTLNPLLYFTIEFDNTVATIEAEYGTIAKPGFNKISTFDVTRKLPYLKIDVFARIPSILLPSKTWQQEMGLQDEKLQTIFDKINSNQDIHLDSFHLPINLSFDSAASIRLYNHHWITLDNGLGKINISIDYKPSRNKPLSIDDFDLLKVIGKGSFGKVMQVRKKDTQKVYALKAIRKSYIVSKSEVTHTLAERTVLARVDCPFIVPLKFSFQSPEKLYFVLAFINGGELFYHLQKEGRFDLSRARFYTAELLCALDNLHKLDVVYRDLKPENILLDYQGHIALCDFGLCKLNMKDDDKTDTFCGTPEYLAPELLLGLGYTKAVDWWTLGVLLYEMLTGLPPYYDEDVPKMYKKILQEPLVFPDGFDRDAKDLLIGLLSRDPTRRLGYNGADEIRNHPFFSQLSWKRLLMKGYIPPYKPAVSNSMDTSNFDEEFTREKPIDSVVDEYLSESVQKQFGGWTYVGNEQLGSSMVQGRSIR