Analysis Of Transcriptome,Proteome And Ubiquitination Induced By Ethylene In Corollas Of Petunias

Petal senescence is a complex programmed process.It has been previously demonstrated that treatment with ethylene,a plant hormone involved in senescence,can extensively alter transcriptome and proteome profiles in plants.However,little is known regarding the impact of ethylene on post-translational modification(PTM)or the association between PTM and the proteome.Protein degradation is one of the hallmarks of senescence,and ubiquitination,a major PTM in eukaryotes,plays important roles in protein degradation.However,no attempts have been made to perform PTM analysis to characterize the ubiquitination of the proteome or the association between modifications and the proteome during flower senescence in response to ethylene.In this study,we first obtained reference petunia transcriptome data via RNA sequencing.Next,we quantitatively investigated the petunia proteome,ubiquitylome,and the association between them in petunia corollas following ethylene treatment,The main results are as follows:1.In total,51,99 unigenes,3,606 proteins,and 2,2 0 ubiquitination sites were quantified 16 hours after ethylene treatment.2.After treatment with ethylene.In the transcriptome,14,448 down-regulated and6,303 up-regulated Unigenes;In the proteome,284 down-regulated and 233 up-regulated proteins,and 320 up-regulated and 12 down-regulated ubiquitination sites in the ubiquitylome.The result indicated that global ubiquitination levels increase during ethylene-mediated corolla senescence in petunia.3.The global proteome and ubiquitylome were negatively correlated and several putative ubiquitin ligases were up-regulated at the protein and transcription levels.Our results showed that ubiquitination could be involved in the degradation of proteins duringethylene-mediated corolla senescence in petunias.And some non-proteasome proteases and autophagocyanates are also involved protein degradation.4.The sequence properties of ubiquitinated proteins were analyzed.In the 3,265 Kub polypeptides,five conserved sequences were identified from 1,3 3 unique sites,of which four conserved sequences have not been reported.The Kub sites was predicted on the secondary structure of the protein,and the high frequency of the ubiquitinated lysine site was in the non-structural region of the protein.The evolutionary conservatism of ubiquitinated lysine and non-ubiquitinated lysine in plants was studied,the results show that ubiquitinated lysine but not non-ubiquitinated lysine is more conservative.5.Ethylene regulates hormone signaling transduction and sucrose biosynthesis and transport pathways at both the protein and ubiquitination levels in petunia corollas.In addition,our results revealed that ethylene increases the ubiquitination levels of proteins involved in endoplasmic reticulum-associated degradation.Ethylene regulates biosynthesis of volatile organic compounds and synthesis of amino acid at the protein level.In addition,ethylene treatment has increased the level of ubiquitination of proteins involved in the degradation pathway associated with endoplasmic reticulum.And a number of new ubiquitination sites in several proteins including Ph ETR2,Ph ACO,Ph Cb5 s and Ph AUX1 was found.