Project description:Lysine acetylation and succinylation are post-translational modifications of proteins, and have been shown to play roles in plant response to pathogen infection. Phytoplasma infection can directly alter multiple metabolic processes in Paulownia and lead to Paulownia witches’ broom (PaWB), the major cause of Paulownia mortality worldwide. To explore the extent and function of lysine acylations during phytoplasma infection, we investigated global proteome, acetylome, and succinylome of phytoplasma-infected Paulownia tomentosa seedlings. In total, we globally yield 8963 proteins, 2893 acetylated, and 1271 succinylated proteins. Among them, 425 substrates were simultaneously acetylated and succinylated. Comparative analysis revealed that 276 proteins, 546 acetylated proteins and 5 succinylated proteins were associated with PaWB. Our results suggested that acetylation may be more important than succinylation in response to phytoplasma infection. Enzymatic assays showed that acetylation modified the activities of protochlorophyllide reductase and RuBisCO in phytoplasma-infected seedlings. On the basis of these results, a model to elucidate the molecular mechanism responses to PaWB was proposed and this research offer a resource for functional studies on the effects of acetylation on protein function.
Project description:BackgroundJWB phytoplasma is a kind of insect-transmitted and uncultivable bacterial plant pathogen causeing a destructive Jujube disease. To date, no genome information about JWB phytoplasma has been published, which hindered its characterization at genomic level. To understand its pathogenicity and ecology, the genome of a JWB phytoplasma isolate jwb-nky was sequenced and compared with other phytoplasmas enabled us to explore the mechanisms of genomic rearrangement.ResultsThe complete genome sequence of JWB phytoplasma (jwb-nky) was determined, which consisting of one circular chromosome of 750,803 bp with a GC content of 23.3%. 694 protein-encoding genes, 2 operons for rRNA genes and 31 tRNA genes as well as 4 potential mobile units (PMUs) containing clusters of DNA repeats were identified. Based on PHIbaes analysis, a large number of genes were genome-specific and approximately 13% of JWB phytoplasma genes were predicted to be associated with virulence. Although transporters for maltose, dipeptides/oligopeptides, spermidine/putrescine, cobalt, Mn/Zn and methionine were identified, KEGG pathway analysis revealed the reduced metabolic capabilities of JWB phytoplasma. Comparative genome analyses between JWB phytoplasma and other phytoplasmas shows the occurrence of large-scale gene rearrangements. The low synteny with other phytoplasmas indicated that the expansion of multiple gene families/duplication probably occurred separately after differentiation.ConclusionsIn this study, the complete genome sequence of a JWB phytoplasma isolate jwb-nky that causing JWB disease was reported for the first time and a number of species-specific genes were identified in the genome. The study enhanced our understandings about genomic basis and the pathogenicity mechanism of this pathogen, which will aid in the development of improved strategies for efficient management of JWB diseases.