4eag

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Template:STRUCTURE 4eag

Contents 1 Co-crystal structure of an chimeric AMPK core with ATP 2 Function 3 About this Structure 4 Reference

Co-crystal structure of an chimeric AMPK core with ATP

Template:ABSTRACT PUBMED 22659875

Function

[AAKG1_RAT] AMP/ATP-binding subunit of AMP-activated protein kinase (AMPK), an energy sensor protein kinase that plays a key role in regulating cellular energy metabolism. In response to reduction of intracellular ATP levels, AMPK activates energy-producing pathways and inhibits energy-consuming processes: inhibits protein, carbohydrate and lipid biosynthesis, as well as cell growth and proliferation. AMPK acts via direct phosphorylation of metabolic enzymes, and by longer-term effects via phosphorylation of transcription regulators. Also acts as a regulator of cellular polarity by remodeling the actin cytoskeleton; probably by indirectly activating myosin. Gamma non-catalytic subunit mediates binding to AMP, ADP and ATP, leading to activate or inhibit AMPK: AMP-binding results in allosteric activation of alpha catalytic subunit (PRKAA1 or PRKAA2) both by inducing phosphorylation and preventing dephosphorylation of catalytic subunits. ADP also stimulates phosphorylation, without stimulating already phosphorylated catalytic subunit. ATP promotes dephosphorylation of catalytic subunit, rendering the AMPK enzyme inactive.^{[1] [2]} [AAKB1_RAT] Non-catalytic subunit of AMP-activated protein kinase (AMPK), an energy sensor protein kinase that plays a key role in regulating cellular energy metabolism. In response to reduction of intracellular ATP levels, AMPK activates energy-producing pathways and inhibits energy-consuming processes: inhibits protein, carbohydrate and lipid biosynthesis, as well as cell growth and proliferation. AMPK acts via direct phosphorylation of metabolic enzymes, and by longer-term effects via phosphorylation of transcription regulators. Also acts as a regulator of cellular polarity by remodeling the actin cytoskeleton; probably by indirectly activating myosin. Beta non-catalytic subunit acts as a scaffold on which the AMPK complex assembles, via its C-terminus that bridges alpha (PRKAA1 or PRKAA2) and gamma subunits (PRKAG1, PRKAG2 or PRKAG3).

About this Structure

4eag is a 3 chain structure with sequence from Buffalo rat and Drome. Full crystallographic information is available from OCA.

Reference

• Chen L, Wang J, Zhang YY, Yan SF, Neumann D, Schlattner U, Wang ZX, Wu JW. AMP-activated protein kinase undergoes nucleotide-dependent conformational changes. Nat Struct Mol Biol. 2012 Jun 3;19(7):716-8. doi: 10.1038/nsmb.2319. PMID:22659875 doi:http://dx.doi.org/10.1038/nsmb.2319

1. ↑ Xiao B, Heath R, Saiu P, Leiper FC, Leone P, Jing C, Walker PA, Haire L, Eccleston JF, Davis CT, Martin SR, Carling D, Gamblin SJ. Structural basis for AMP binding to mammalian AMP-activated protein kinase. Nature. 2007 Sep 27;449(7161):496-500. Epub 2007 Sep 12. PMID:17851531 doi:10.1038/nature06161
2. ↑ Xiao B, Sanders MJ, Underwood E, Heath R, Mayer FV, Carmena D, Jing C, Walker PA, Eccleston JF, Haire LF, Saiu P, Howell SA, Aasland R, Martin SR, Carling D, Gamblin SJ. Structure of mammalian AMPK and its regulation by ADP. Nature. 2011 Apr 14;472(7342):230-3. Epub 2011 Mar 13. PMID:21399626 doi:10.1038/nature09932