Dataset Information

Rubisco acetylation stoichiometry in Arabidopsis Thaliana

ABSTRACT: Multiple studies have shown Rubisco to be subject to Lys-acetylation at various residues; however, conflicting reports exist about the biological significance of these post-translational modifications. One aspect of the Lys-acetylation that has not been addressed in plants generally, or with Rubisco specifically, is the stoichiometry at which these Lys-acetylation events occur. As a method to ascertain which Lys-acetylation sites on Arabidopsis Rubisco might be of regulatory importance, we purified Rubisco from leaves in both the day and night-time and performed independent mass-spectrometry based methods to determine the stoichiometry of Rubisco Lys-acetylation events.

INSTRUMENT(S): Orbitrap Fusion

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

TISSUE(S): Leaf

SUBMITTER: Brendan O'Leary

LAB HEAD: Harvey Millar

PROVIDER: PXD019268 | Pride | 2020-09-28

REPOSITORIES: Pride

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Rubisco lysine acetylation occurs at very low stoichiometry in mature Arabidopsis leaves: implications for regulation of enzyme function.

O'Leary Brendan M BM Scafaro Andrew P AP Fenske Ricarda R Duncan Owen O Ströher Elke E Petereit Jakob J Millar A Harvey AH

The Biochemical journal 20201001 19

Multiple studies have shown ribulose-1,5-bisphosphate carboxylase/oxygenase (E.C. 4.1.1.39; Rubisco) to be subject to Lys-acetylation at various residues; however, opposing reports exist about the biological significance of these post-translational modifications. One aspect of the Lys-acetylation that has not been addressed in plants generally, or with Rubisco specifically, is the stoichiometry at which these Lys-acetylation events occur. As a method to ascertain which Lys-acetylation sites on A ...[more]

PMID: 32959870

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Project description:Background: Lysine crotonylation (Kcr), as a novel evolutionarily conserved type of PTM, is ubiquitous and essential in cell biology. However, its functions in tea plant, an important beverage crop, are largely unknown. Our study firstly attempted to describe Kcr proteins in tea leaves under NH4+ deficiency/resupply, and provided significant insights into exploring the physiological role of Kcr in plants for N utilization. Results: We performed the global analysis of crotonylome in tea plants under NH4+ deficiency/resupply using high-resolution LC-MS/MS coupled with highly sensitive immune-antibody. A total of 2288 kcr sites on 971 proteins were identified, of which contained in 15 types of Kcr motifs. Most of Kcr proteins were located in chloroplast and cytoplasm. 120 and 151 Kcr proteins were significantly changed at 3 hours and 3days of NH4+ resupply, respectively. Bioinformatics analysis showed that differentially expressed Kcr proteins participated in diverse biological processes such as photosynthesis, carbon fixation and amino acid metabolism, suggesting Kcr plays important roles in these processes. Interestingly, a large number of enzymes were crotonylated, and the activity and Kcr level of these enzymes changed significantly after NH4+ resupply, indicating a potential function of Kcr in the regulation of enzyme activities. Moreover, the protein-protein interaction analysis revealed that the diverse interactions of identified Kcr proteins mainly involved in photosynthesis, carbon fixation, amino acid metabolism and ribosome. Conclusions: The results suggested that lysine crotonylated proteins might play regulating roles in metabolic process in tea leaves under NH4+ deficiency/resupply. The critical regulatory roles mainly involved in diverse aspects of primary metabolic processes, especially in photosynthesis, carbon fixation and amino acid metabolism. The provided data may serve as important resources for exploring the physiological, biochemical, and genetic role of lysine crotonylation in tea plants.

			Action	DRS
	AcetylKSites.txt	Txt
	BO_RBL_Day1.raw	Raw
	BO_RBL_Day2.raw	Raw
	BO_RBL_Night1.raw	Raw
	BO_RBL_Night2.raw	Raw