Identification of a Novel AMP-activated Protein Kinase β Subunit Isoform That Is Highly Expressed in Skeletal Muscle

摘要: The AMP-activated protein kinase (AMPK) is a member of growing family related kinases, including the SNF1 complex in yeast, which respond to nutritional stress. AMPK heterotrimeric catalytic subunit (α) and two regulatory subunits (β γ), proteins all three have been identified complex. We used two-hybrid system order identify interacting with (α2). Using this approach, we isolated novel AMPKβ isoform, designate AMPKβ2. N-terminal region β2 differs significantly from that previously characterized isoform (β1), suggesting could play role isoform-specific activity. Comparison C-terminal sequences β1 their yeast identifies highly conserved regions predicted be involved binding α γ subunits. expression was examined number tissues, revealing expressed liver low skeletal muscle, whereas opposite pattern observed for isoform. These results suggest β isoforms tissue-specific roles, may involve altered responses upstream signaling and/or downstream targeting