TIC236 gain-of-function mutations unveil the link between plastid division and plastid protein import

Proc Natl Acad Sci U S A. 2022 Mar 15;119(11):e2123353119. doi: 10.1073/pnas.2123353119. Epub 2022 Mar 11.

Abstract

SignificanceAlthough plastid division is critical for plant development, how components of the plastid division machinery (PDM) are imported into plastids remains unexplored. A forward genetic screen to identify suppressors of a crumpled leaf (crl) mutant deficient in plastid division led us to find dominant gain-of-function (GF) mutations in TIC236, which significantly increases the import of PDM components and completely rescues crl phenotypes. The defective plastid division phenotypes in crl and tic236-knockdown mutants and CRL-TIC236 association in a functional complex indicate that the CRL-TIC236 module is vital for plastid division. Hence, we report the first GF translocon mutants and unveil CRL as a novel functional partner of TIC236 for PDM import.

Keywords: TIC236; cell death; chloroplast; plastid division; protein import defect.

MeSH terms

  • Arabidopsis Proteins* / genetics
  • Arabidopsis Proteins* / metabolism
  • Arabidopsis* / cytology
  • Arabidopsis* / genetics
  • Arabidopsis* / metabolism
  • Cell Division*
  • Chloroplast Proteins* / genetics
  • Chloroplast Proteins* / metabolism
  • Gain of Function Mutation
  • Membrane Transport Proteins* / genetics
  • Membrane Transport Proteins* / metabolism
  • Plastids* / genetics
  • Plastids* / metabolism
  • Protein Transport

Substances

  • AT2G25660 protein, Arabidopsis
  • Arabidopsis Proteins
  • Chloroplast Proteins
  • Membrane Transport Proteins