論文

査読有り
2010年6月

Mechanism for the regulation of mammalian cGMP phosphodiesterase6. 1: Identification of its inhibitory subunit complexes and their roles

MOLECULAR AND CELLULAR BIOCHEMISTRY
  • Akio Yamazaki
  • ,
  • Vladimir A. Bondarenko
  • ,
  • Isao Matsuura
  • ,
  • Masahiro Tatsumi
  • ,
  • Sadamu Kurono
  • ,
  • Naoka Komori
  • ,
  • Hiroyuki Matsumoto
  • ,
  • Fumio Hayashi
  • ,
  • Russell K. Yamazaki
  • ,
  • Jiro Usukura

339
1-2
開始ページ
215
終了ページ
233
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1007/s11010-010-0387-8
出版者・発行元
SPRINGER

Cyclic GMP phosphodiesterase (PDE) in bovine rod photoreceptor outer segments (OS) comprises a catalytic subunit complex (P alpha beta) and two inhibitory subunits (P gamma) and is regulated by the alpha subunit of transducin (T alpha). Here, we show an overall mechanism for PDE regulation by identifying P gamma complexes in OS homogenates prepared with an isotonic buffer. Before T alpha activation, three P gamma complexes exist in the soluble fraction. Complex a, a minor complex, contains P alpha beta, T alpha, and a protein named P delta. Complex b, P alpha beta gamma gamma (b) , has a PDE activity similar to that of membranous P alpha beta gamma gamma, P alpha beta gamma gamma (M) , and its level, although its large portion is P delta-free, is estimated to be 20-30% of the total P alpha beta gamma gamma. Complex c, (P gamma center dot GDP-T alpha) (2) (c) , appears to be a dimer of P gamma center dot GDP-T alpha. Upon T alpha activation, (1) complex a stays unchanged, (2) P alpha beta gamma gamma (b) binds to membranes, (3) the level of (P gamma center dot GDP-T alpha) (2) (c) is reduced as its GTP-form is produced, (4) complex d, P gamma center dot GTP-T alpha (d) , is formed on membranes and its substantial amount is released to the soluble fraction, and (5) membranous P alpha beta gamma gamma, P alpha beta gamma gamma (M) and/or P alpha beta gamma gamma (b) , becomes P gamma-depleted. These observations indicate that P gamma as a complex with GTP-T alpha dissociates from P alpha beta gamma gamma on membranes and is released to the soluble fraction and that P gamma-depleted PDE is the GTP-T alpha-activated PDE. After GTP hydrolysis, both (P gamma center dot GDP-T alpha) (2) (c) and P gamma center dot GDP-T alpha (d) , without liberating P gamma, deactivate P gamma-depleted PDE. The preferential order to be used for the deactivation is membranous P gamma center dot GDP-T alpha (d) , solubilized P gamma center dot GDP-T alpha (d) and (P gamma center dot GDP-T alpha) (2) (c) . Release of P gamma center dot GTP-T alpha complexes to the soluble fraction is relevant to light adaptation.

リンク情報
DOI
https://doi.org/10.1007/s11010-010-0387-8
CiNii Articles
http://ci.nii.ac.jp/naid/80021023838
PubMed
https://www.ncbi.nlm.nih.gov/pubmed/20151179
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000277432000022&DestApp=WOS_CPL
ID情報
  • DOI : 10.1007/s11010-010-0387-8
  • ISSN : 0300-8177
  • CiNii Articles ID : 80021023838
  • PubMed ID : 20151179
  • Web of Science ID : WOS:000277432000022

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