Crosstalk between the chloroplast protein import and SUMO systems revealed through genetic and molecular investigation in Arabidopsis

Watson, Samuel J.; Li, Na; Ye, Yiting; Wu, Feijie; Ling, Qihua; Jarvis, Paul

doi:10.7554/elife.60960

Cited by 15 publications

(14 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The rapid decomposition of TOC complexes mediated by chloroplastassociated protein degradation (CHLORAD) has been reported for the decrease in the transportation efficiency of chloroplast preproteins under stress conditions (Ling et al, 2012(Ling et al, , 2019. Two recent works showed the function of SUMOylation in the regulation of the TOC components: SUMOylation partially protects TOC159 from UPS-mediated degradation under a low gibberellic acid condition during early development (Accossato et al, 2020); SUMOylation components regulate the CLORAD pathway to coordinate the destruction of the TOC complex (Watson et al, 2021). However, the functions of SUMO conjugations on chloroplast preproteins are completely unknown.…”

Section: Discussionmentioning

confidence: 99%

“…Thus, SUMOylation directly improves the importation efficiency of chloroplast preproteins to maintain the function of chloroplasts under HS, possibly antagonizing the impact of the excessive degradation of TOC. Given that the stability of TOC components is also modulated by SUMOylation (Accossato et al ., 2020; Watson et al ., 2021), it will be interesting to dissertate the balance mechanism of chloroplast protein importation mediated via the cooperation of SUMOylation on preproteins and TOC components under HS.…”

Section: Discussionmentioning

confidence: 99%

“…A previous screening using yeast two‐hybrid and proteomics identified several potential SUMOylated chloroplast proteins (Elrouby & Coupland, 2010; Lopez‐Torrejon et al ., 2013), but the biological functions of SUMOylation on these substrates are completely unknown. Two recent studies showed that SUMOylation targets the TOC complex; SUMOylation partially stabilizes TOC159 under a low gibberellic acid condition during early development (Accossato et al ., 2020); the SUMO system directly regulates protein stability of the TOC complex in chloroplast development (Watson et al ., 2021). However, there is no report on the functional characterization of SUMOylated proteins inside chloroplasts or the molecular mechanism of SUMOylation in the regulation of these chloroplast‐targeted proteins under HS.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Importation of chloroplast proteins under heat stress is facilitated by their SUMO conjugations

et al. 2022

View full text Add to dashboard Cite

Chloroplasts are hypersensitive to heat stress (HS). SUMOylation, a critical posttranslational modification, is conservatively involved in HS responses. However, the functional connection between SUMOylation and chloroplasts under HS remains to be studied.The bioinformatics, biochemistry, and cell biology analyses were used to detect the SUMOylation statuses of Arabidopsis nuclear-encoded chloroplast proteins and the effect of SUMOylation on subcellular localization of these proteins under HS. PSBR, a subunit of photosystem II, was used as an example for a detailed investigation of functional mechanisms.After a global SUMOylation site prediction of nuclear-encoded chloroplast proteins, biochemical data showed that most of the selected candidates are modified by SUMO3 in the cytoplasm. The chloroplast localization of these SUMOylation targets under long-term HS is partially maintained by the SUMO ligase AtSIZ1. The HS-induced SUMOylation on PSBR contributes to the maintenance of its chloroplast localization, which is dependent on its chloroplast importation efficiency correlated to phosphorylation. The complementation analysis provided evidence that SUMOylation is essential for the physiological function of PSBR under HS.Our study illustrated a general regulatory mechanism of SUMOylation in maintaining the chloroplast protein importation during HS and provided hints for further investigation on protein modifications associated with plant organelles under stress conditions.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Importation of chloroplast proteins under heat stress is facilitated by their SUMO conjugations

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Subsequent analysis has shown that Toc159 SUMOylation protects Toc159 from UPS-dependent degradation prior to TOC assembly [ 91 ]. On the other hand, like the sp1 mutants, Arabidopsis mutants for a number of components in the SUMO pathway including SUMO2 and SUMO3 can partially suppress the phenotypes of the ppi1 mutant for Toc33 through improving chloroplast development and enhancing accumulation of key Toc proteins [ 92 ]. Therefore, the SUMO system can both stabilize and destabilize key Toc proteins, probably dependent on different biological contexts.…”

Section: Chloroplast-associated Protein Degradation (Chlorad)mentioning

confidence: 99%

Chloroplasts Protein Quality Control and Turnover: A Multitude of Mechanisms

Fan

et al. 2022

IJMS

View full text Add to dashboard Cite

As the organelle of photosynthesis and other important metabolic pathways, chloroplasts contain up to 70% of leaf proteins with uniquely complex processes in synthesis, import, assembly, and turnover. Maintaining functional protein homeostasis in chloroplasts is vitally important for the fitness and survival of plants. Research over the past several decades has revealed a multitude of mechanisms that play important roles in chloroplast protein quality control and turnover under normal and stress conditions. These mechanisms include: (i) endosymbiotically-derived proteases and associated proteins that play a vital role in maintaining protein homeostasis inside the chloroplasts, (ii) the ubiquitin-dependent turnover of unimported chloroplast precursor proteins to prevent their accumulation in the cytosol, (iii) chloroplast-associated degradation of the chloroplast outer-membrane translocon proteins for the regulation of chloroplast protein import, (iv) chloroplast unfolded protein response triggered by accumulated unfolded and misfolded proteins inside the chloroplasts, and (v) vesicle-mediated degradation of chloroplast components in the vacuole. Here, we provide a comprehensive review of these diverse mechanisms of chloroplast protein quality control and turnover and discuss important questions that remain to be addressed in order to better understand and improve important chloroplast functions.

show abstract

“…Furthermore, the interaction between AtHSC70-4 and AtCHIP is not under the precondition that AtCHIP ubiquitinates AtHSC70-4, but is predicated on the basis that AtHSC70-4 and AtCHIP together mediate plastid precursor degradation (Lee et al, 2009 ). Therefore, the interaction between AtHSC70-4 and AtSCE1 mediates plastid precursor SUMOylation (Watson et al, 2021 ). There are multiple examples of Ub-protein ligases interacting with the same substrate, including anaphase-promoting complex AtAPC11, AtPUB59, and AtPUB60 interacting with AtPRP8B and AtJMJ24, AtPUB59, and AtPUB60 binding a nuclear matrix protein-like protein complex THOC (AtTHO1 and AtTHO3) and more.…”

Section: The Regulation Of As Through Ptmsmentioning

confidence: 99%

Ubiquitination and Ubiquitin-Like Modifications as Mediators of Alternative Pre-mRNA Splicing in Arabidopsis thaliana

Lan

Qiu

et al. 2022

Front. Plant Sci.

View full text Add to dashboard Cite

Alternative splicing (AS) is a common post-transcriptional regulatory process in eukaryotes. AS has an irreplaceable role during plant development and in response to environmental stress as it evokes differential expression of downstream genes or splicing factors (e.g., serine/arginine-rich proteins). Numerous studies have reported that loss of AS capacity leads to defects in plant growth and development, and induction of stress-sensitive phenotypes. A role for post-translational modification (PTM) of AS components has emerged in recent years. These modifications are capable of regulating the activity, stability, localization, interaction, and folding of spliceosomal proteins in human cells and yeast, indicating that PTMs represent another layer of AS regulation. In this review, we summarize the recent reports concerning ubiquitin and ubiquitin-like modification of spliceosome components and analyze the relationship between spliceosome and the ubiquitin/26S proteasome pathway in plants. Based on the totality of the evidence presented, we further speculate on the roles of protein ubiquitination mediated AS in plant development and environmental response.

show abstract

Crosstalk between the chloroplast protein import and SUMO systems revealed through genetic and molecular investigation in Arabidopsis

Cited by 15 publications

References 53 publications

Importation of chloroplast proteins under heat stress is facilitated by their SUMO conjugations

Importation of chloroplast proteins under heat stress is facilitated by their SUMO conjugations

Chloroplasts Protein Quality Control and Turnover: A Multitude of Mechanisms

Ubiquitination and Ubiquitin-Like Modifications as Mediators of Alternative Pre-mRNA Splicing in Arabidopsis thaliana

Contact Info

Product

Resources

About