Importance of the Balance Between Protein Synthesis and Degradation in Chloroplasts Revealed by the Studies of Arabidopsis Yellow Variegated Mutants

  • Eiko Miura
  • Yusuke Kato
  • Wataru Sakamoto
Conference paper

Abstract

In Arabidopsis, yellow variegated (var) is one of the best characterized among the mutants showing leaf variegation. VAR1 and VAR2 encode different FtsH proteases (FtsH5 and FtsH2, respectively) involved in the quality control of chloroplast proteins, particularly in the turnover of D1 reaction center protein. To investigate the precise role of FtsH in protein degradation and understand how the variegated sectors are formed, we recently identified a suppressor of var2 named fug1. Characterization of the fug1 locus showed that it encodes a chloroplast translation initiation factor 2 (cpIF2) and indeed acts on chloroplast protein synthesis. Based on this suppressor analysis, we hypothesized that the balance between protein synthesis and degradation determines leaf variegation in var mutants. Here, we present another type of evidence that supports our hypothesis, by supplementing var2 with exogenous translational inhibitors.

Keywords

Chloroplast leaf variegation protease translation 

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References245

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Copyright information

© Springer Science + Business Media, B.V. 2008

Authors and Affiliations

  • Eiko Miura
    • 1
  • Yusuke Kato
    • 1
  • Wataru Sakamoto
    • 1
  1. 1.Research Institute for BioresourcesOkayama UniversityKurashiki, OkayamaJapan

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