The FtsH-inactive Protein TSL2/FtsHi5 Is Required for Chloroplast Development and Proteostasis at Low Ambient Temperature in Arabidopsis thaliana

ABSTRACT: Chloroplasts are indispensable for higher plants. The growth and development of plants are very sensitive to environmental temperature changes, and chloroplast development is also regulated by adverse environmental temperatures. However, the molecular mechanism of how plants coordinate chloroplast development and environmental temperature changes remains largely unknown. Here, a temperature-conditioned chloroplast development defect mutant tsl2 (thermo-sensitive mutant in leaf color 2) of Arabidopsis was obtained through forward genetic screening. The tsl2 mutant showed a weak yellowing phenotype at 22 °C which was more pronounced when the growth temperature was reduced to 16 °C, and was similar to that of the wild type when the temperature was increased to 29 °C. Genomic resequencing analysis revealed that TSL2 gene encodes the FtsHi5 which was shown to function in chloroplast protein import. Genetic complementation analysis showed that TSL2 rescued the chlorophyll content and thylakoid development defects in tls2 mutants at 16 °C. Quantitative mass spectrometry analysis with Tandem Mass Tag (TMT) isobaric labeling revealed broad changes in the proteome composition of tsl2 chloroplasts at low temperature, reflecting impaired chloroplast biogenesis and function. Together, our data suggest that TSL2 has a significant role in chloroplast development and proteostasis especially at low environmental temperatures.

INSTRUMENT(S): Orbitrap Exploris 480

ORGANISM(S): Arabidopsis Thaliana (mouse-ear Cress)

TISSUE(S): Leaf

SUBMITTER: Jinyu Li  

LAB HEAD: Jianxiang Liu

PROVIDER: PXD030185 | Pride | 2022-01-21

REPOSITORIES: Pride