Abstract
An emerging area in plant research focuses on antagonism between regulatory systems governing growth and immunity. Such cross talk represents a point of vulnerability for pathogens to exploit. AVR2, an RXLR effector secreted by the potato blight pathogen Phytophthora infestans, interacts with potato BSL1, a putative phosphatase implicated in growth-promoting brassinosteroid (BR) hormone signaling. Transgenic potato (Solanum tuberosum) plants expressing the effector exhibit transcriptional and phenotypic hallmarks of overactive BR signaling and show enhanced susceptibility to P. infestans. Microarray analysis was used to identify a set of BR-responsive marker genes in potato, all of which are constitutively expressed to BR-induced levels in AVR2 transgenic lines. One of these genes was a bHLH transcription factor, designated StCHL1, homologous to AtCIB1 and AtHBI1, which are known to facilitate antagonism between BR and immune responses. Transient expression of either AVR2 or CHL1 enhanced leaf colonization by P. infestans and compromised immune cell death activated by perception of the elicitin Infestin1 (INF1). Knockdown of CHL1 transcript using Virus-Induced Gene Silencing (VIGS) reduced colonization of P. infestans on Nicotiana benthamiana. Moreover, the ability of AVR2 to suppress INF1-triggered cell death was attenuated in NbCHL1-silenced plants, indicating that NbCHL1 was important for this effector activity. Thus, AVR2 exploits cross talk between BR signaling and innate immunity in Solanum species, representing a novel, indirect mode of innate immune suppression by a filamentous pathogen effector.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 9
Claim · model-written summary
The pathogen effector AVR2 interacts with potato BSL1.
- Taxon
- potato
Solanum tuberosume0 - Interactor
- Phytophthora infestans
Phytophthora infestanse0pathogen - Gene
- potato BSL1e0
- Outcome
- interacts with potato BSL1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“AVR2, an RXLR effector secreted by the potato blight pathogen Phytophthora infestans, interacts with potato BSL1”
Claim · model-written summary
Potato plants expressing AVR2 showed hallmarks of elevated brassinosteroid signaling.
- Taxon
- potatoSolanum tuberosume0
- Gene
- BR signalinge0
- Outcome
- transcriptional and phenotypic hallmarks of overactive BR signalinge0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Transgenic potato (Solanum tuberosum) plants expressing the effector exhibit transcriptional and phenotypic hallmarks of overactive BR signaling”
Claim · model-written summary
AVR2 expressing potato plants showed enhanced susceptibility to P. infestans.
- Taxon
- potatoSolanum tuberosume0
- Interactor
- P. infestansPhytophthora infestanse0pathogen
- Outcome
- susceptibility to P. infestanse0
- Direction
- enhancede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Transgenic potato (Solanum tuberosum) plants expressing the effector exhibit transcriptional and phenotypic hallmarks of overactive BR signaling and show enhanced susceptibility to P. infestans”
Claim · model-written summary
Identified potato BR-responsive marker genes were constitutively expressed at BR-induced levels in AVR2 lines.
- Taxon
- potatoSolanum tuberosume0
- Material
- AVR2 transgenic linese0
- Gene
- BR-responsive marker genese0
- Outcome
- constitutively expressed to BR-induced levelse0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a set of BR-responsive marker genes in potato, all of which are constitutively expressed to BR-induced levels in AVR2 transgenic lines”
Claim · model-written summary
One identified BR-responsive gene was designated StCHL1 and encoded a bHLH transcription factor.
Not reportedTaxonDirection
Verbatim
e0“One of these genes was a bHLH transcription factor, designated StCHL1, homologous to AtCIB1 and AtHBI1”
Claim · model-written summary
Transient AVR2 expression enhanced P. infestans leaf colonization.
- Treatment
- Transient expression of either AVR2 or CHL1e0
- Interactor
- P. infestansPhytophthora infestanse0pathogen
- Outcome
- leaf colonization by P. infestanse0
- Direction
- enhancede0
Not reportedTaxonComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Transient expression of either AVR2 or CHL1 enhanced leaf colonization by P. infestans”
Claim · model-written summary
Transient expression of AVR2 or CHL1 compromised INF1-triggered immune cell death.
- Treatment
- Transient expression of either AVR2 or CHL1e0
- Interactor
- P. infestansPhytophthora infestanse0pathogen
- Outcome
- immune cell deathe0
- Direction
- compromisede0
Not reportedTaxonComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Transient expression of either AVR2 or CHL1 enhanced leaf colonization by P. infestans and compromised immune cell death activated by perception of the elicitin Infestin1 (INF1)”
Claim · model-written summary
CHL1 silencing reduced P. infestans colonization on Nicotiana benthamiana.
- Taxon
- Nicotiana benthamiana
Nicotiana benthamianae0 - Treatment
- Knockdown of CHL1 transcript using Virus-Induced Gene Silencing (VIGS)e0
- Interactor
- P. infestansPhytophthora infestanse0pathogen
- Gene
- CHL1e0
- Outcome
- colonization of P. infestanse0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Knockdown of CHL1 transcript using Virus-Induced Gene Silencing (VIGS) reduced colonization of P. infestans on Nicotiana benthamiana”
Claim · model-written summary
Silencing NbCHL1 attenuated AVR2 suppression of INF1-triggered cell death.
- Treatment
- NbCHL1-silenced plantse0
- Gene
- NbCHL1e0
- Outcome
- ability of AVR2 to suppress INF1-triggered cell deathe0
- Direction
- attenuatede0
Not reportedTaxonComparator
Verbatim
e0“the ability of AVR2 to suppress INF1-triggered cell death was attenuated in NbCHL1-silenced plants”
t0“RXLR Effector AVR2 Up-Regulates a Brassinosteroid-Responsive bHLH Transcription Factor to Suppress Immunity”
The same questions in other papers
loss of function · Phytophthora infestans · Nicotiana benthamianaPositive and negative results
6 papers in the same direction as this paper · 21 in the opposite direction
- negative
- negative
- positive
24 papers more in this group
See all 28 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.