National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
F31GM116441
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
DP2AI117923
米国
引用
ジャーナル: Science / 年: 2020 タイトル: Polymerization in the actin ATPase clan regulates hexokinase activity in yeast. 著者: Patrick R Stoddard / Eric M Lynch / Daniel P Farrell / Annie M Dosey / Frank DiMaio / Tom A Williams / Justin M Kollman / Andrew W Murray / Ethan C Garner / 要旨: The actin fold is found in cytoskeletal polymers, chaperones, and various metabolic enzymes. Many actin-fold proteins, such as the carbohydrate kinases, do not polymerize. We found that Glk1, a ...The actin fold is found in cytoskeletal polymers, chaperones, and various metabolic enzymes. Many actin-fold proteins, such as the carbohydrate kinases, do not polymerize. We found that Glk1, a glucokinase, forms two-stranded filaments with ultrastructure that is distinct from that of cytoskeletal polymers. In cells, Glk1 polymerized upon sugar addition and depolymerized upon sugar withdrawal. Polymerization inhibits enzymatic activity; the Glk1 monomer-polymer equilibrium sets a maximum rate of glucose phosphorylation regardless of Glk1 concentration. A mutation that eliminated Glk1 polymerization alleviated concentration-dependent enzyme inhibition. Yeast containing nonpolymerizing Glk1 were less fit when growing on sugars and more likely to die when refed glucose. Glk1 polymerization arose independently from other actin-related filaments and may allow yeast to rapidly modulate glucokinase activity as nutrient availability changes.