Protein import-independent functions of Tic56, a component of the 1-MDa translocase at the inner chloroplast envelope membrane. (4th March 2017)

• Record Type: Journal Article
• Authors: Agne, Birgit; Köhler, Daniel; Baginsky, Sacha
• Is Part Of: Plant signaling & behavior. Volume 12:Number 3(2017)
• Publication Date: 2017-03-04
• Subjects: Chloroplast -- protein import -- quantitative proteomics -- translocon at the inner chloroplast envelope membrane; Plant ecophysiology -- Periodicals; Plant cellular signal transduction -- Periodicals; Plant cellular signal transduction; Plant ecophysiology; Periodicals; Electronic journals; 581
• DOI: 10.1080/15592324.2017.1284726
• Languages: English
• ISSNs: 1559-2316

Abstract

ABSTRACT: Tic56 is an essential subunit of a 1-MDa protein complex at the inner chloroplast envelope membrane that comprises Tic100, Tic214 and the protein conducting channel protein Tic20-I. The complex was characterized as the "general protein import translocase" because mutants in either of its subunits have a severe growth phenotype and fail to assemble a photosynthetic machinery. In a recent publication we show that the albino phenotype of tic56–1 mutants results at least in part from a defect in ribosome assembly and a deficiency in plastid translation. We furthermore could not detect any impairment of protein import activity with plastids from tic56–3 mutants, despite a lack of full-length Tic56 and a decreased abundance of other 1-MDa complex subunits. These findings suggest that the 1-MDa complex consists of subunits that have functions other than protein import.