Diversity and Function of Appressoria

et al. 2022

Front. Microbiol.

Biotrophic plant pathogenic fungi are widely distributed and are among the most damaging pathogenic organisms of agriculturally important crops responsible for significant losses in quality and yield. However, the pathogenesis of obligate parasitic pathogenic microorganisms is still under investigation because they cannot reproduce and complete their life cycle on an artificial medium. The successful lifestyle of biotrophic fungal pathogens depends on their ability to secrete effector proteins to manipulate or evade plant defense response. By integrating genomics, transcriptomics, and effectoromics, insights into how the adaptation of biotrophic plant fungal pathogens adapt to their host populations can be gained. Efficient tools to decipher the precise molecular mechanisms of rust–plant interactions, and standardized routines in genomics and functional pipelines have been established and will pave the way for comparative studies. Deciphering fungal pathogenesis not only allows us to better understand how fungal pathogens infect host plants but also provides valuable information for plant diseases control, including new strategies to prevent, delay, or inhibit fungal development. Our review provides a comprehensive overview of the efforts that have been made to decipher the effector proteins of biotrophic fungal pathogens and demonstrates how rapidly research in the field of obligate biotrophy has progressed.

Section: Biotrophic Plant Fungal Pathogens Infection Strategiesmentioning

confidence: 99%

Infection Strategies and Pathogenicity of Biotrophic Plant Fungal Pathogens

Mapuranga

et al. 2022

Front. Microbiol.

“…Appressorial melanization, as occurring in Colletotrichum , Magnaporthe , Polystigma , and in Phyllosticta species, differs clearly from hyphal cell wall melanization with respect to cell specificity of polymer formation and localization of the product [ 34 , 35 ]. In appressoria, melanin is localized in the cell wall in direct proximity of the appressorial plasma membrane, and not at the outer cell wall layer, arguing against a role as a ROS scavenger.…”

Section: Cell Wall Polymers Are Major Determinants In the C...mentioning

confidence: 99%

Fungal Pathogenesis-Related Cell Wall Biogenesis, with Emphasis on the Maize Anthracnose Fungus Colletotrichum graminicola

Silva

Aliyeva-Schnorr

Wirsel

et al. 2022

Plants

The genus Colletotrichum harbors many plant pathogenic species, several of which cause significant yield losses in the field and post harvest. Typically, in order to infect their host plants, spores germinate, differentiate a pressurized infection cell, and display a hemibiotrophic lifestyle after plant invasion. Several factors required for virulence or pathogenicity have been identified in different Colletotrichum species, and adaptation of cell wall biogenesis to distinct stages of pathogenesis has been identified as a major pre-requisite for the establishment of a compatible parasitic fungus–plant interaction. Here, we highlight aspects of fungal cell wall biogenesis during plant infection, with emphasis on the maize leaf anthracnose and stalk rot fungus, Colletotrichum graminicola.

“…As a biotrophy fungus similar to U. maydis , U. esculenta continuously draws nutrition from the host to proliferate and extend by entering into the plant cell wall, therefore it is necessary to break through the first layer of the plant defense network, the plant cell wall [ 8 , 9 , 10 ]. There are diverse strategies existed, e.g., hemibiotroph fungi such as Magnaporthe oryzae and Colletotrichum species possess melanized appressorium with extremely high turgor pressure, which converts to mechanical pressure to help with going through the plant cuticle and plant cell wall [ 11 , 12 ]. Biotrophs such as U. maydis and U. hordei have non-melanized appressorium and facilitate penetration of the cuticle and plant cell wall by secretion of plant cell wall degrading enzymes (CWDEs) and mechanical force [ 13 , 14 ].…”

Section: Introductionmentioning

confidence: 99%

An Endoglucanase Secreted by Ustilago esculenta Promotes Fungal Proliferation

Bian

et al. 2022

JoF

Ustilago esculenta is a fungus of two morphological forms, among the filamentous dikaryon that can induce the plant stem to expand to form fleshy stem. In order to establish biotrophy with Zizania latifolia which belongs to the tribe Oryzeae (Poaceae), U. esculenta firstly needs to secrete a bunch of effectors, among them being cell wall degrading enzymes (CWDEs). We have isolated a gene, UeEgl1, which was differentially expressed in MT-type and T-type U. esculenta at an early stage of infection, and specifically induced in the filamentous growth of the T-type. Bioinformatics analysis and enzyme activity assay indicated that UeEgl1 functions outside the cell as a β-1,4-endoglucanase with a conserved domain of the glycosyl hydrolase family 45 (GH45) which targets the main component of the plant cell wall β-1,4 linked glycosidic bonds. The phenotype analysis of UeEgl1 deletion mutants and UeEgl1 over-expression transformants showed that UeEgl1 had no significant effect on the budding, cell fusion, and filamentous growth of U. esculenta in vitro. Further study found that over-expression of UeEgl1 promoted the proliferation of mycelia inside Z. latifolia, and raised plant defense responses. The above results show that the UeEgl1 gene may play an important role in the early stage of infection through the decomposition of the plant cell wall.