3TNQ

Structure and Allostery of the PKA RIIb Tetrameric Holoenzyme

3TNQ の概要

• エントリーDOI: 10.2210/pdb3tnq/pdb
• 関連するPDBエントリー: 3TNP 3TNR
• 分子名称: Protein kinase, cAMP-dependent, catalytic, alpha, cAMP-dependent protein kinase type II-beta regulatory subunit, MAGNESIUM ION, ... (5 entities in total)
• 機能のキーワード: pka riib tetrameric holoenzyme, transferase
• 由来する生物種: Rattus norvegicus (rat); 詳細
• 細胞内の位置: Cytoplasm (By similarity): A1L1M0
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 87567.03

構造登録者

Zhang, P.,Smith-Nguyen, E.V.,Keshwani, M.M.,Deal, M.S.,Kornev, A.P.,Taylor, S.S. (登録日: 2011-09-01, 公開日: 2012-02-01, 最終更新日: 2012-09-26)

主引用文献

Zhang, P.,Smith-Nguyen, E.V.,Keshwani, M.M.,Deal, M.S.,Kornev, A.P.,Taylor, S.S.
Structure and allostery of the PKA RIIbeta tetrameric holoenzyme
Science, 335:712-716, 2012

PubMed Abstract: In its physiological state, cyclic adenosine monophosphate (cAMP)-dependent protein kinase (PKA) is a tetramer that contains a regulatory (R) subunit dimer and two catalytic (C) subunits. We describe here the 2.3 angstrom structure of full-length tetrameric RIIβ(2):C(2) holoenzyme. This structure showing a dimer of dimers provides a mechanistic understanding of allosteric activation by cAMP. The heterodimers are anchored together by an interface created by the β4-β5 loop in the RIIβ subunit, which docks onto the carboxyl-terminal tail of the adjacent C subunit, thereby forcing the C subunit into a fully closed conformation in the absence of nucleotide. Diffusion of magnesium adenosine triphosphate (ATP) into these crystals trapped not ATP, but the reaction products, adenosine diphosphate and the phosphorylated RIIβ subunit. This complex has implications for the dissociation-reassociation cycling of PKA. The quaternary structure of the RIIβ tetramer differs appreciably from our model of the RIα tetramer, confirming the small-angle x-ray scattering prediction that the structures of each PKA tetramer are different.

PubMed: 22323819
DOI: 10.1126/science.1213979

実験手法

X-RAY DIFFRACTION (3.097 Å)