scholarly journals Role of MPK4 in pathogen-associated molecular pattern-triggered alternative splicing in Arabidopsis

2019 ◽  
Author(s):  
Jeremie Bazin ◽  
Kiruthiga Mariappan ◽  
Thomas Blein ◽  
Ronny Voelz ◽  
Martin Crespi ◽  
...  
Keyword(s):  
Alternative Splicing ◽  
Protein Kinases ◽  
Transcriptome Analysis ◽  
Splicing Factors ◽  
Transcriptional Level ◽  
Mitogen Activated Protein Kinases ◽  
Molecular Pattern ◽  
Mitogen Activated Protein ◽  
Alternatively Spliced ◽  
Pathogen Associated Molecular Pattern

AbstractAlternative splicing (AS) of pre-mRNAs in plants is an important mechanism of gene regulation in environmental stress tolerance but plant signals involved are essentially unknown. Pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) is mediated by mitogen-activated protein kinases and the majority of PTI defense genes are regulated by MPK3, MPK4 and MPK6. These responses have been mainly analyzed at the transcriptional level, however many splicing factors are direct targets of MAPKs. Here, we studied alternative splicing induced by the PAMP flagellin in Arabidopsis. We identified 506 PAMP-induced differentially alternatively spliced (DAS) genes. Although many DAS genes are targets of nonsense-mediated degradation (NMD), only 19% are potential NMD targets. Importantly, of the 506 PAMP-induced DAS genes, only 89 overlap with the set of 1849 PAMP-induced differentially expressed genes (DEG), indicating that transcriptome analysis does not identify most DASevents. Global DAS analysis of mpk3, mpk4, and mpk6 mutants revealed that MPK4 is a key regulator of PAMP-induced differential splicing, regulating AS of a number of splicing factors and immunity-related protein kinases, such as the calcium-dependent protein kinase CPK28, the cysteine-rich receptor like kinases CRK13 and CRK29 or the FLS2 co-receptor SERK4/BKK1. These data suggest that MAP kinase regulation of splicing factors is a key mechanism in PAMP-induced AS regulation of PTI.Significance statementAlternative pre-mRNA splicing (AS) affects plant responses to environmental stresses. So far, however, the regulation of AS is little understood. Here, we studied AS induced by the pathogen-associated molecular pattern (PAMP) flagellin in Arabidopsis. We identified 506 differentially alternatively spliced (DAS) genes, 89 of which overlap with the 1849 DEG, indicating that the majority of DAS events go undetected by common transcriptome analysis. PAMP-triggered immunity is mediated by mitogen-activated protein kinases. Global DAS analysis of MAPK mutants revealed that MPK4 is a key regulator of AS by affecting splicing factors and a number of important protein kinases involved in immunity. Since PAMP-triggered phosphorylation of several splicing factors is directly mediated by MAPKs, we discovered a key mechanism of AS regulation.

scholarly journals Vigilant Keratinocytes Trigger Pathogen-Associated Molecular Pattern Signaling in Response to Streptococcal M1 Protein

2015 ◽  
Vol 83 (12) ◽  
pp. 4673-4681 ◽  
Author(s):  
Sandra T. Persson ◽  
Laura Wilk ◽  
Matthias Mörgelin ◽  
Heiko Herwald
Keyword(s):  
Protein Kinases ◽  
Inflammatory Mediators ◽  
Intracellular Signaling ◽  
Protective Mechanism ◽  
Mitogen Activated Protein Kinases ◽  
M1 Protein ◽  
Molecular Pattern ◽  
Superficial Skin ◽  
Mitogen Activated Protein ◽  
Pathogen Associated Molecular Pattern

The human skin exerts many functions in order to maintain its barrier integrity and protect the host from invading microorganisms. One such pathogen isStreptococcus pyogenes, which can cause a variety of superficial skin wounds that may eventually progress into invasive deep soft tissue infections. Here we show that keratinocytes recognize soluble M1 protein, a streptococcal virulence factor, as a pathogen-associated molecular pattern to release alarming inflammatory responses. We found that this interaction initiates an inflammatory intracellular signaling cascade involving the activation of the mitogen-activated protein kinases extracellular signal-regulated kinase (ERK), p38, and Jun N-terminal protein kinase and the subsequent induction and mobilization of the transcription factors NF-κB and AP-1. We also determined the imprint of the inflammatory mediators released, such as interleukin-8 (IL-8), growth-related oncogene alpha, migration inhibitory factor, extracellular matrix metalloproteinase inducer, IL-1α, IL-1 receptor a, and ST2, in response to streptococcal M1 protein. The expression of IL-8 is dependent on Toll-like receptor 2 activity and subsequent activation of the mitogen-activated protein kinases ERK and p38. Notably, this signaling seems to be distinct for IL-8 release, and it is not shared with the other inflammatory mediators. We conclude that keratinocytes participate in a proinflammatory manner in streptococcal pattern recognition and that expression of the chemoattractant IL-8 by keratinocytes constitutes an important protective mechanism against streptococcal M1 protein.

scholarly journals Melanin Biosynthesis in the Maize Pathogen Cochliobolus heterostrophus Depends on Two Mitogen-Activated Protein Kinases, Chk1 and Mps1, and the Transcription Factor Cmr1

2007 ◽  
Vol 6 (3) ◽  
pp. 421-429 ◽  
Author(s):  
Noa Eliahu ◽  
Aeid Igbaria ◽  
Mark S. Rose ◽  
Benjamin A. Horwitz ◽  
Sophie Lev
Keyword(s):  
Transcription Factor ◽  
Protein Kinases ◽  
Noncoding Rna ◽  
Magnaporthe Grisea ◽  
Cochliobolus Heterostrophus ◽  
Transcriptional Level ◽  
Melanin Biosynthesis ◽  
Mitogen Activated Protein Kinases ◽  
Mitogen Activated Protein ◽  
Hyperosmotic Environment

ABSTRACT The maize pathogen Cochliobolus heterostrophus requires two mitogen-activated protein kinases (MAPKs), Chk1 and Mps1, to produce normal pigmentation. Young colonies of mps1 and chk1 deletion mutants have a white and autolytic appearance, which was partially rescued by a hyperosmotic environment. We isolated the transcription factor Cmr1, an ortholog of Colletotrichum lagenarium Cmr1 and Magnaporthe grisea Pig1, which regulates melanin biosynthesis in C. heterostrophus. Deletion of CMR1 in C. heterostrophus resulted in mutants that lacked dark pigmentation and acquired an orange-pink color. In cmr1 deletion strains the expression of putative scytalone dehydratase (SCD1) and hydroxynaphthalene reductase (BRN1 and BRN2) genes involved in melanin biosynthesis was undetectable, whereas expression of PKS18, encoding a polyketide synthase, was only moderately reduced. In chk1 and mps1 mutants expression of PKS18, SCD1, BRN1, BRN2, and the transcription factor CMR1 itself was very low in young colonies, slightly up-regulated in aging colonies, and significantly induced in hyperosmotic conditions, compared to invariably high expression in the wild type. These findings indicate that two MAPKs, Chk1 and Mps1, affect Cmr1 at the transcriptional level and this influence is partially overridden in stress conditions including aging culture and hyperosmotic environment. Surprisingly, we found that the CMR1 gene was transcribed in both sense and antisense directions, apparently producing mRNA as well as a long noncoding RNA transcript. Expression of the antisense CMR1 was also Chk1 and Mps1 dependent. Analysis of chromosomal location of the melanin biosynthesis genes in C. heterostrophus resulted in identification of a small gene cluster comprising BRN1, CMR1, and PKS18. Since expression of all three genes depends on Chk1 and Mps1 MAPKs, we suggest their possible epigenetic regulation.

scholarly journals Mitogen activated protein kinases function as a cohort during a plant defense response

2018 ◽  
Author(s):  
Brant T. McNeece ◽  
Keshav Sharma ◽  
Gary W. Lawrence ◽  
Kathy S. Lawrence ◽  
Vincent P. Klink
Keyword(s):  
Gene Expression ◽  
Signal Transduction ◽  
Protein Kinases ◽  
Defense Response ◽  
Defense Genes ◽  
Root Cells ◽  
Mitogen Activated Protein Kinases ◽  
Molecular Pattern ◽  
Mitogen Activated Protein ◽  
Effector Triggered Immunity

ABSTRACTMitogen activated protein kinases (MAPKs) play important signal transduction roles. However, little is known regarding whether MAPKs influence the gene expression of other family members and the relationship that expression has to a biological process. Transcriptomic studies have identified MAPK gene expression occurring within root cells undergoing a defense response to a pathogenic event in the allotetraploidGlycine max. Furthermore, functional analyses are presented for its 32 MAPKs revealing 9 of the 32 MAPKs have a defense role, including homologs ofArabidopsis thalianaMAPK (MPK) MPK2, MPK3, MPK4, MPK5, MPK6, MPK13, MPK16 and MPK20. Defense signal transduction processes occurring through pathogen activated molecular pattern (PAMP) triggered immunity (PTI) and effector triggered immunity (ETI) have been determined in relation to these MAPKs. PTI has been analyzed by examiningBOTRYTIS INDUCED KINASE1(BIK1),ENHANCED DISEASE SUSCEPTIBILITY1(EDS1) andLESION SIMULATING DISEASE1(LSD1). ETI has been analyzed by examining the role of the bacterial effector protein harpin and the downstream cell membrane receptorNON-RACE SPECIFIC DISEASE RESISTANCE1(NDR1). Experiments have identified 5 different types of gene expression relating to MAPK expression. The MAPKs are shown to influence PTI and ETI gene expression and a panel of proven defense genes including an ABC-G type transporter, 20S membrane fusion particle components, glycoside biosynthesis, carbon metabolism, hemicellulose modification, transcription andPATHOGENESIS RELATED 1(PR1). The experiments show MAPKs broadly influence the expression of other defense MAPKs, including the co-regulation of parologous MAPKs and reveal its relationship to proven defense genes.

Sign in / Sign up

Export Citation Format

Share Document