Dynamic expression of Ralstonia solanacearum virulence factors and metabolism-controlling genes during plant infection
de Pedro Jové, Roger (Centre de Recerca en Agrigenòmica)
Puigvert, Marina (Centre de Recerca en Agrigenòmica)
Sebastià, Pau (Centre de Recerca en Agrigenòmica)
Macho, Alberto P. (Chinese Academy of Sciences)
Monteiro, Freddy (Universidade de São Paulo. Departamento de Bioquímica (Brazil))
Sánchez Coll, Núria (Centre de Recerca en Agrigenòmica)
Setubal, João C. (Universidade de São Paulo. Departamento de Bioquímica (Brazil))
Valls, Marc (Centre de Recerca en Agrigenòmica)

Date:	2021
Abstract:	Background: Ralstonia solanacearum is the causal agent of bacterial wilt, a devastating plant disease responsible for serious economic losses especially on potato, tomato, and other solanaceous plant species in temperate countries. In R. solanacearum, gene expression analysis has been key to unravel many virulence determinants as well as their regulatory networks. However, most of these assays have been performed using either bacteria grown in minimal medium or in planta, after symptom onset, which occurs at late stages of colonization. Thus, little is known about the genetic program that coordinates virulence gene expression and metabolic adaptation along the different stages of plant infection by R. solanacearum. Results: We performed an RNA-sequencing analysis of the transcriptome of bacteria recovered from potato apoplast and from the xylem of asymptomatic or wilted potato plants, which correspond to three different conditions (Apoplast, Early and Late xylem). Our results show dynamic expression of metabolism-controlling genes and virulence factors during parasitic growth inside the plant. Flagellar motility genes were especially up-regulated in the apoplast and twitching motility genes showed a more sustained expression in planta regardless of the condition. Xylem-induced genes included virulence genes, such as the type III secretion system (T3SS) and most of its related effectors and nitrogen utilisation genes. The upstream regulators of the T3SS were exclusively up-regulated in the apoplast, preceding the induction of their downstream targets. Finally, a large subset of genes involved in central metabolism was exclusively down-regulated in the xylem at late infection stages. Conclusions: This is the first report describing R. solanacearum dynamic transcriptional changes within the plant during infection. Our data define four main genetic programmes that define gene pathogen physiology during plant colonisation. The described expression of virulence genes, which might reflect bacterial states in different infection stages, provides key information on the R. solanacearum potato infection process.
Grants:	Ministerio de Economía y Competitividad PID2019-108595RB-I00 Ministerio de Economía y Competitividad SEV-2015-0533 European Commission 713673
Note:	Altres ajuts: CERCA Programme/Generalitat de Catalunya. P. Sebastià received the support of a fellowship (code is LCF/BQ/IN17/11620004) from la Caixa Foundation (identifier [ID] 100010434)
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Ralstonia solanacearum ; Bacterial wilt ; RNAseq ; Virulence factors ; Dynamic gene expression ; Metabolism ; T3SS ; Effectors ; Xylem ; Apoplast
Published in:	BMC genomics, Vol. 22 (March 2021) , art. 170, ISSN 1471-2164

DOI: 10.1186/s12864-021-07457-w
PMID: 33750302

18 p, 2.1 MB

The record appears in these collections:
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > CRAG (Centre for Research in Agricultural Genomics)
Articles > Research articles
Articles > Published articles