Dissecting the role of histidine kinase and HOG1 mitogen-activated protein kinase signalling in stress tolerance and pathogenicity of Parastagonospora nodorum on wheat

نویسندگان

  • Evan John
  • Francisco Lopez-Ruiz
  • Kasia Rybak
  • Carl J. Mousley
  • Richard P. Oliver
  • Kar-Chun Tan
چکیده

The HOG1 mitogen-activated protein kinase (MAPK) pathway is activated through two-component histidine kinase (HK) signalling. This pathway was first characterized in the budding yeast Saccharomyces cerevisiae as a regulator of osmotolerance. The fungus Parastagonospora nodorum is the causal agent of septoria nodorum blotch of wheat. This pathogen uses host-specific effectors in tandem with general pathogenicity mechanisms to carry out its infection process. Genes showing strong sequence homology to S. cerevisiae HOG1 signalling pathway genes have been identified in the genome of P. nodorum. In this study, we examined the role of the pathway in the virulence of P. nodorum on wheat by disrupting putative pathway component genes: HOG1 (SNOG_13296) MAPK and NIK1 (SNOG_11631) hybrid HK. Mutants deleted in NIK1 and HOG1 were insensitive to dicarboximide and phenylpyrrole fungicides, but not a fungicide that targets ergosterol biosynthesis. Furthermore, both Δnik1 and Δhog1 mutants showed increased sensitivity to hyperosmotic stress. However, HOG1, but not NIK1, is required for tolerance to elevated temperatures. HOG1 deletion conferred increased tolerance to 6-methoxy-2-benzoxazolinone, a cereal phytoalexin. This suggests that the HOG1 signalling pathway is not exclusively associated with NIK1. Both Δnik1 and Δhog1 mutants retained the ability to infect and cause necrotic lesions on wheat. However, we observed that the Δhog1 mutation resulted in reduced production of pycnidia, asexual fruiting bodies that facilitate spore dispersal during late infection. Our study demonstrated the overlapping and distinct roles of a HOG1 MAPK and two-component HK signalling in P. nodorum growth and pathogenicity.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Comparison of MAPK and thioredoxin gene expression in wheat seedlings exposed to silver nitrate and silver nanoparticle

The extensive use of heavy metals and nanoparticles (NPs) has led to their release into the environment that might have negative impacts on both organisms and the environment. In this study, the molecular responses of wheat seedlings to silver nitrate and silver nanoparticles (AgNPs) were assessed by transcript accumulation analysis of genes coding for products potentially involved in heavy met...

متن کامل

Inactivation of mitogen-activated protein kinase signaling pathway reduces caspase-14 expression in impaired keratinocytes

Objective(s):Several investigations have revealed that caspase-14 is responsible for the epidermal differentiation and cornification, as well as the regulation of moisturizing effect. However, the precise regulation mechanism is still not clear. This study was aimed to investigate the expression of caspase-14 in filaggrin-deficient normal human epidermal keratinocytes (NHEKs) and to explore the...

متن کامل

Iranian crack induces hepatic injury through mitogen-activated protein kinase pathway in the liver of Wistar rat

Objective(s): Iranian crack (IC) is a heroin-based substance manifesting various pathologic side effects. Herein, we aimed to investigate the mechanism of IC-induced liver injuries in Wistar rats. Materials and Methods: Twenty male Wistar rats were randomly divided into two groups: control, and IC (0.9 mg/kg/day/IP, for 30 days). Mitochondrial reactive oxygen species (ROS) production was measur...

متن کامل

Group III histidine kinase is a positive regulator of Hog1-type mitogen-activated protein kinase in filamentous fungi.

We previously reported that the group III histidine kinase Dic1p in the maize pathogen Cochliobolus heterostrophus is involved in resistance to dicarboximide and phenylpyrrole fungicides and in osmotic adaptation. In addition, exposure to the phenylpyrrole fungicide fludioxonil led to improper activation of Hog1-type mitogen-activated protein kinases (MAPKs) in some phytopathogenic fungi, inclu...

متن کامل

Anti-inflammatory Effects of Oxymatrine Through Inhibition of Nuclear Factor–kappa B and Mitogen-activated Protein Kinase Activation in Lipopolysaccharide-induced BV2 Microglia Cells

Oxymatrine, a potent monosomic alkaloid extracted from Chinese herb Sophora japonica (Sophora flavescens Ait.). possesses anti-inflammatory activittyes.  This study was designed to investigate the effects of oxymatrine on nuclear factor–kappa B (NF-κB) and mitogen-activated protein kinase (MAPK)-dependent inflammatory responses in lipopolysaccharide (LPS)-activated microglia. In this paper, BV2...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره 162  شماره 

صفحات  -

تاریخ انتشار 2016