A Small <italic toggle="yes">Wolbachia</italic> Protein Directly Represses Phage Lytic Cycle Genes in “<italic toggle="yes">Candidatus</italic> Liberibacter asiaticus” within Psyllids

ABSTRACT Huanglongbing (HLB) is a severe disease of citrus caused by an uncultured alphaproteobacterium “Candidatus Liberibacter asiaticus” and transmitted by Asian citrus psyllids (Diaphorina citri). Two prophage genomes, SC1 and SC2, integrated in “Ca. Liberibacter asiaticus” strain UF506 were des...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Mukesh Jain, Laura A. Fleites, Dean W. Gabriel
Formato:	article
Lenguaje:	EN
Publicado:	American Society for Microbiology 2017
Materias:	Huanglongbing Wolbachia citrus greening cross talk holin phage repressor Microbiology QR1-502
Acceso en línea:	https://doaj.org/article/a5bfae4ae89346eb861f75f5d8b42a23
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:a5bfae4ae89346eb861f75f5d8b42a23
record_format	dspace
spelling	oai:doaj.org-article:a5bfae4ae89346eb861f75f5d8b42a232021-11-15T15:21:45ZA Small <italic toggle="yes">Wolbachia</italic> Protein Directly Represses Phage Lytic Cycle Genes in “<italic toggle="yes">Candidatus</italic> Liberibacter asiaticus” within Psyllids10.1128/mSphereDirect.00171-172379-5042https://doaj.org/article/a5bfae4ae89346eb861f75f5d8b42a232017-06-01T00:00:00Zhttps://journals.asm.org/doi/10.1128/mSphereDirect.00171-17https://doaj.org/toc/2379-5042ABSTRACT Huanglongbing (HLB) is a severe disease of citrus caused by an uncultured alphaproteobacterium “Candidatus Liberibacter asiaticus” and transmitted by Asian citrus psyllids (Diaphorina citri). Two prophage genomes, SC1 and SC2, integrated in “Ca. Liberibacter asiaticus” strain UF506 were described previously, and very similar prophages are found resident in the majority of “Ca. Liberibacter asiaticus” strains described worldwide. The SC1 lytic cycle is marked by upregulation of prophage late genes, including a functional holin (SC1_gp110); these late genes are activated when “Ca. Liberibacter asiaticus” is in planta, but not when infecting the psyllid host. We previously reported that the holin promoter is strongly and constitutively active in Liberibacter crescens (a cultured proxy for uncultured “Ca. Liberibacter asiaticus”) but is suppressed in a dose-dependent manner by crude aqueous extracts from D. citri applied exogenously. Here we report that the suppressor activity of the crude psyllid extract was heat labile and abolished by proteinase K treatment, indicating a proteinaceous repressor and of a size smaller than 30 kDa. The repressor was affinity captured from D. citri aqueous extracts using biotinylated holin promoter DNA immobilized on magnetic beads and subjected to liquid chromatography-tandem mass spectrometry (LC-MS/MS). Protein database interrogation was used to identify a small DNA-binding protein encoded by a gene carried by Wolbachia strain wDi, a resident endosymbiont of D. citri as the repressor. The in vitro-translated Wolbachia repressor protein was able to penetrate L. crescens cells, bind to “Ca. Liberibacter asiaticus” promoter DNA, and partially suppress holin promoter-driven β-glucuronidase (GUS) activity, indicating potential involvement of an additional interacting partner(s) or posttranslational modification(s) for complete suppression. Expression of the Wolbachia repressor protein appeared to be constitutive irrespective of “Ca. Liberibacter asiaticus” infection status of the insect host. IMPORTANCE Host acquisition of a new microbial species can readily perturb the dynamics of preexisting microbial associations. Molecular cross talk between microbial associates may be necessary for efficient resource allocation and enhanced survival. Classic examples involve quorum sensing (QS), which detects population densities and is both used and coopted to control expression of bacterial genes, including host adaptation factors. We report that a 56-amino-acid repressor protein made by the resident psyllid endosymbiont Wolbachia can enter cells of Liberibacter crescens, a cultured proxy for the uncultured psyllid endosymbiont “Ca. Liberibacter asiaticus” and repress “Ca. Liberibacter asiaticus” phage lytic cycle genes. Such repression in “Ca. Liberibacter asiaticus” may be critical to survival of both endosymbionts, since phage-mediated lysis would likely breach the immunogenic threshold of the psyllid, invoking a systemic and nonspecific innate immune reaction.Mukesh JainLaura A. FleitesDean W. GabrielAmerican Society for MicrobiologyarticleHuanglongbingWolbachiacitrus greeningcross talkholinphage repressorMicrobiologyQR1-502ENmSphere, Vol 2, Iss 3 (2017)
institution	DOAJ
collection	DOAJ
language	EN
topic	Huanglongbing Wolbachia citrus greening cross talk holin phage repressor Microbiology QR1-502
spellingShingle	Huanglongbing Wolbachia citrus greening cross talk holin phage repressor Microbiology QR1-502 Mukesh Jain Laura A. Fleites Dean W. Gabriel A Small <italic toggle="yes">Wolbachia</italic> Protein Directly Represses Phage Lytic Cycle Genes in “<italic toggle="yes">Candidatus</italic> Liberibacter asiaticus” within Psyllids
description	ABSTRACT Huanglongbing (HLB) is a severe disease of citrus caused by an uncultured alphaproteobacterium “Candidatus Liberibacter asiaticus” and transmitted by Asian citrus psyllids (Diaphorina citri). Two prophage genomes, SC1 and SC2, integrated in “Ca. Liberibacter asiaticus” strain UF506 were described previously, and very similar prophages are found resident in the majority of “Ca. Liberibacter asiaticus” strains described worldwide. The SC1 lytic cycle is marked by upregulation of prophage late genes, including a functional holin (SC1_gp110); these late genes are activated when “Ca. Liberibacter asiaticus” is in planta, but not when infecting the psyllid host. We previously reported that the holin promoter is strongly and constitutively active in Liberibacter crescens (a cultured proxy for uncultured “Ca. Liberibacter asiaticus”) but is suppressed in a dose-dependent manner by crude aqueous extracts from D. citri applied exogenously. Here we report that the suppressor activity of the crude psyllid extract was heat labile and abolished by proteinase K treatment, indicating a proteinaceous repressor and of a size smaller than 30 kDa. The repressor was affinity captured from D. citri aqueous extracts using biotinylated holin promoter DNA immobilized on magnetic beads and subjected to liquid chromatography-tandem mass spectrometry (LC-MS/MS). Protein database interrogation was used to identify a small DNA-binding protein encoded by a gene carried by Wolbachia strain wDi, a resident endosymbiont of D. citri as the repressor. The in vitro-translated Wolbachia repressor protein was able to penetrate L. crescens cells, bind to “Ca. Liberibacter asiaticus” promoter DNA, and partially suppress holin promoter-driven β-glucuronidase (GUS) activity, indicating potential involvement of an additional interacting partner(s) or posttranslational modification(s) for complete suppression. Expression of the Wolbachia repressor protein appeared to be constitutive irrespective of “Ca. Liberibacter asiaticus” infection status of the insect host. IMPORTANCE Host acquisition of a new microbial species can readily perturb the dynamics of preexisting microbial associations. Molecular cross talk between microbial associates may be necessary for efficient resource allocation and enhanced survival. Classic examples involve quorum sensing (QS), which detects population densities and is both used and coopted to control expression of bacterial genes, including host adaptation factors. We report that a 56-amino-acid repressor protein made by the resident psyllid endosymbiont Wolbachia can enter cells of Liberibacter crescens, a cultured proxy for the uncultured psyllid endosymbiont “Ca. Liberibacter asiaticus” and repress “Ca. Liberibacter asiaticus” phage lytic cycle genes. Such repression in “Ca. Liberibacter asiaticus” may be critical to survival of both endosymbionts, since phage-mediated lysis would likely breach the immunogenic threshold of the psyllid, invoking a systemic and nonspecific innate immune reaction.
format	article
author	Mukesh Jain Laura A. Fleites Dean W. Gabriel
author_facet	Mukesh Jain Laura A. Fleites Dean W. Gabriel
author_sort	Mukesh Jain
title	A Small <italic toggle="yes">Wolbachia</italic> Protein Directly Represses Phage Lytic Cycle Genes in “<italic toggle="yes">Candidatus</italic> Liberibacter asiaticus” within Psyllids
title_short	A Small <italic toggle="yes">Wolbachia</italic> Protein Directly Represses Phage Lytic Cycle Genes in “<italic toggle="yes">Candidatus</italic> Liberibacter asiaticus” within Psyllids
title_full	A Small <italic toggle="yes">Wolbachia</italic> Protein Directly Represses Phage Lytic Cycle Genes in “<italic toggle="yes">Candidatus</italic> Liberibacter asiaticus” within Psyllids
title_fullStr	A Small <italic toggle="yes">Wolbachia</italic> Protein Directly Represses Phage Lytic Cycle Genes in “<italic toggle="yes">Candidatus</italic> Liberibacter asiaticus” within Psyllids
title_full_unstemmed	A Small <italic toggle="yes">Wolbachia</italic> Protein Directly Represses Phage Lytic Cycle Genes in “<italic toggle="yes">Candidatus</italic> Liberibacter asiaticus” within Psyllids
title_sort	small <italic toggle="yes">wolbachia</italic> protein directly represses phage lytic cycle genes in “<italic toggle="yes">candidatus</italic> liberibacter asiaticus” within psyllids
publisher	American Society for Microbiology
publishDate	2017
url	https://doaj.org/article/a5bfae4ae89346eb861f75f5d8b42a23
work_keys_str_mv	AT mukeshjain asmallitalictoggleyeswolbachiaitalicproteindirectlyrepressesphagelyticcyclegenesinitalictoggleyescandidatusitalicliberibacterasiaticuswithinpsyllids AT lauraafleites asmallitalictoggleyeswolbachiaitalicproteindirectlyrepressesphagelyticcyclegenesinitalictoggleyescandidatusitalicliberibacterasiaticuswithinpsyllids AT deanwgabriel asmallitalictoggleyeswolbachiaitalicproteindirectlyrepressesphagelyticcyclegenesinitalictoggleyescandidatusitalicliberibacterasiaticuswithinpsyllids AT mukeshjain smallitalictoggleyeswolbachiaitalicproteindirectlyrepressesphagelyticcyclegenesinitalictoggleyescandidatusitalicliberibacterasiaticuswithinpsyllids AT lauraafleites smallitalictoggleyeswolbachiaitalicproteindirectlyrepressesphagelyticcyclegenesinitalictoggleyescandidatusitalicliberibacterasiaticuswithinpsyllids AT deanwgabriel smallitalictoggleyeswolbachiaitalicproteindirectlyrepressesphagelyticcyclegenesinitalictoggleyescandidatusitalicliberibacterasiaticuswithinpsyllids
_version_	1718428148763197440

A Small <italic toggle="yes">Wolbachia</italic> Protein Directly Represses Phage Lytic Cycle Genes in “<italic toggle="yes">Candidatus</italic> Liberibacter asiaticus” within Psyllids

Ejemplares similares