Structures of AMP-activated protein kinase bound to novel pharmacological activators in phosphorylated, non-phosphorylated, and nucleotide-free states

Yan Yan, X. Edward Zhou, Scott J. Novick, Simon J. Shaw, Yingwu Li, Joseph S. Brunzelle, Yasumichi Hitoshi, Patrick R. Griffin, H. Eric Xu, Karsten Melcher*

*Corresponding author for this work

Research output: Contribution to journalArticle

3 Scopus citations


AMP-activated protein kinase (AMPK) is an attractive therapeutic target for managing metabolic diseases. A class of pharmacological activators, including Merck 991, binds the AMPK ADaM site, which forms the interaction surface between the kinase domain (KD) of the -subunit and the carbohydrate-binding module (CBM) of the -subunit. Here, we report the development of two new 991-derivative compounds, R734 and R739, which potently activate AMPK in a variety of cell types, including 2-specific skeletal muscle cells. Surprisingly, we found that they have only minor effects on direct kinase activity of the recombinant121 isoform yet robustly enhance protection against activation loop dephosphorylation. This mode of activation is reminiscent of that of ADP, which activates AMPK by binding to the nucleotide-binding sites in the -subunit, more than 60 Å away from the ADaM site. To understand the mechanisms of full and partial AMPK activation, we determined the crystal structures of fully active phosphorylated AMPK111 bound to AMP and R734/R739 as well as partially active nonphosphorylated AMPK bound to R734 and AMP and phosphorylated AMPK bound to R734 in the absence of added nucleotides at <3-Å resolution. These structures and associated analyses identified a novel conformational state of the AMPK autoinhibitory domain associated with partial kinase activity and provide new insights into phosphorylation-dependent activation loop stabilization in AMPK.

Original languageEnglish (US)
Pages (from-to)953-967
Number of pages15
JournalJournal of Biological Chemistry
Issue number3
Publication statusPublished - Jan 1 2019


ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

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