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Title: Crystal Structures of the Adenylate Sensor from Fission Yeast AMP-Activated Protein Kinase

Abstract

The 5'-AMP (adenosine monophosphate)-activated protein kinase (AMPK) coordinates metabolic function with energy availability by responding to changes in intracellular adenosine triphosphate (ATP) and AMP levels. Here we report crystal structures at 2.6 and 2.9 Angstrom resolution for ATP- and AMP-bound forms of a core {alpha}{beta}{gamma} adenylate-binding domain from the fission yeast AMPK homologue. ATP and AMP bind competitively to a single site in the {gamma} subunit, with their respective phosphate groups positioned near function-impairing mutants. Surprisingly, ATP binds without counter ions, amplifying its electrostatic effects on a critical regulatory region where all three subunits converge.

Authors:
;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
930644
Report Number(s):
BNL-81064-2008-JA
Journal ID: ISSN 0193-4511; SCEHDK; TRN: US200901%%159
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Science; Journal Volume: 315
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ADENOSINE; ATP; AVAILABILITY; CRYSTAL STRUCTURE; ELECTROSTATICS; FISSION; MUTANTS; PHOSPHATES; PHOSPHOTRANSFERASES; PROTEINS; RESOLUTION; YEASTS; national synchrotron light source

Citation Formats

Townley,R., and Shapiro, L.. Crystal Structures of the Adenylate Sensor from Fission Yeast AMP-Activated Protein Kinase. United States: N. p., 2007. Web. doi:10.1126/science.1137503.
Townley,R., & Shapiro, L.. Crystal Structures of the Adenylate Sensor from Fission Yeast AMP-Activated Protein Kinase. United States. doi:10.1126/science.1137503.
Townley,R., and Shapiro, L.. Mon . "Crystal Structures of the Adenylate Sensor from Fission Yeast AMP-Activated Protein Kinase". United States. doi:10.1126/science.1137503.
@article{osti_930644,
title = {Crystal Structures of the Adenylate Sensor from Fission Yeast AMP-Activated Protein Kinase},
author = {Townley,R. and Shapiro, L.},
abstractNote = {The 5'-AMP (adenosine monophosphate)-activated protein kinase (AMPK) coordinates metabolic function with energy availability by responding to changes in intracellular adenosine triphosphate (ATP) and AMP levels. Here we report crystal structures at 2.6 and 2.9 Angstrom resolution for ATP- and AMP-bound forms of a core {alpha}{beta}{gamma} adenylate-binding domain from the fission yeast AMPK homologue. ATP and AMP bind competitively to a single site in the {gamma} subunit, with their respective phosphate groups positioned near function-impairing mutants. Surprisingly, ATP binds without counter ions, amplifying its electrostatic effects on a critical regulatory region where all three subunits converge.},
doi = {10.1126/science.1137503},
journal = {Science},
number = ,
volume = 315,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • AMP-activated protein kinase (AMPK) is a master metabolic regulator, and is an important target for drug development against diabetes, obesity, and other diseases. AMPK is a hetero-trimeric enzyme, with a catalytic ({alpha}) subunit, and two regulatory ({beta} and {gamma}) subunits. Here we report the crystal structure at 2.2 Angstrom resolution of the protein kinase domain (KD) of the catalytic subunit of yeast AMPK (commonly known as SNF1). The Snf1-KD structure shares strong similarity to other protein kinases, with a small N-terminal lobe and a large C-terminal lobe. Two negative surface patches in the structure may be important for the recognitionmore » of the substrates of this kinase.« less
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  • Methylglyoxal, a ubiquitous metabolite derived from glycolysis has diverse physiological functions in yeast cells. Previously, we have reported that extracellularly added methylglyoxal activates Spc1, a stress-activated protein kinase (SAPK), in the fission yeast Schizosaccharomyces pombe [Y. Takatsume, S. Izawa, Y. Inoue, J. Biol. Chem. 281 (2006) 9086-9092]. Phosphorylation of Spc1 by treatment with methylglyoxal in S. pombe cells defective in glyoxalase I, an enzyme crucial for the metabolism of methylglyoxal, continues for a longer period than in wild-type cells. Here we show that methylglyoxal inhibits the activity of the protein phosphatase responsible for the dephosphorylation of Spc1 in vitro. Inmore » addition, we found that methylglyoxal inhibits human protein tyrosine phosphatase 1B (PTP1B) also. We propose a model for the regulation of the activity of the Spc1-SAPK signaling pathway by methylglyoxal in S. pombe.« less
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