Transcripts and tumors: regulatory and metabolic programming during biotrophic phytopathogenesis

Abstract

Biotrophic fungal pathogens of plants must sense and adapt to the host environment to complete their life cycles. Recent transcriptome studies of the infection of maize by the biotrophic pathogen Ustilago maydis are providing molecular insights into an ordered program of changes in gene expression and the deployment of effectors as well as key features of nutrient acquisition. In particular, the transcriptome data provide a deeper appreciation of the complexity of the transcription factor network that controls the biotrophic program of invasion, proliferation, and sporulation. Additionally, transcriptome analysis during tumor formation, a key late stage in the life cycle, revealed features of the remodeling of host and pathogen metabolism that may support the formation of tremendous numbers of spores. Transcriptome studies are also appearing for other smut species during interactions with their hosts, thereby providing opportunities for comparative approaches to understand biotrophic adaptation.

Integrative Analysis of Breast Cancer Cells Reveals an Epithelial-Mesenchymal Transition Role in Adaptation to Acidic Microenvironment

“…Biological networks are used widely to model biological interactions at the molecular level to understand biological processes particularly in the case of cancer (39). To assess biological networks different techniques have been developed; centrality analysis is one of them (40,41). Centrality analysis ranks the nodes (genes in gene regulatory networks) based on their significance.…”

The Unfolded Protein Response Regulates Pathogenic Development of Ustilago maydis by Rok1-Dependent Inhibition of Mating-Type Signaling

“…Another important role of this regulatory connection for biotrophic growth in planta is predicted based on the influence on the b regulatory network. Expression of effector-encoding genes during pathogenic development is mainly controlled by the b heterodimer or b -regulated transcription factors, including Rbf1, Hdp2, and, potentially, Biz1 (10, 28, 29, 40, 56). Their proper folding, processing, and secretion, however, is dependent on a functional UPR (48, 57, 58).…”

Progress in pathogenesis research of Ustilago maydis, and the metabolites involved along with their biosynthesis

“…Early in the infection process, gene regulation of the zinc finger transcription factor Rbf1 is known to be required for the initial steps of pathogenic development, including hyphal formation, induction of G2 cell cycle arrest, and stress‐mediated plant infiltration (Heimel, Scherer, Vranes, et al, 2010 ). The transcription factors Hdp2 and Biz1 downstream of Rbf1 are involved in the multiple regulation of effectors during the biotrophic establishment stage, and 228 effector genes, including important effectors such as Pep1, Pit2, Rsp3, and See1, are up‐regulated (Brefort et al, 2014 ; Lanver et al, 2017 ; Schmitz et al, 2018 ).…”