RNA-Seq Data Analysis: A Practical Guide for Model and Non-Model Organisms.

RNA sequencing (RNA-seq) has emerged as a powerful tool for assessing genome-wide gene expression, revolutionizing various fields of biology. However, analyzing large RNA-seq datasets can be challenging, especially for students or researchers lacking bioinformatics experience. To address these challenges, we present a comprehensive guide to provide step-by-step workflows for analyzing RNA-seq data, from raw reads to functional enrichment analysis, starting with considerations for experimental design. This is designed to aid students and researchers working with any organism, irrespective of whether an assembled genome is available. Within this guide, we employ various recognized bioinformatics tools to navigate the landscape of RNA-seq analysis and discuss the advantages and disadvantages of different tools for the same task. Our protocol focuses on clarity, reproducibility, and practicality to enable users to navigate the complexities of RNA-seq data analysis easily and gain valuable biological insights from the datasets. Additionally, all scripts and a sample dataset are available in a GitHub repository to facilitate the implementation of the analysis pipeline. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Analysis of data from a model plant with an available reference genome Basic Protocol 2: Gene ontology enrichment analysis Basic Protocol 3: De novo assembly of data from non-model plants.

A Global Analysis of Photoreceptor-Mediated Transcriptional Changes Reveals the Intricate Relationship Between Central Metabolism and DNA Repair in the Filamentous Fungus Trichoderma atroviride.

Light provides critical information for the behavior and development of basically all organisms. Filamentous fungi sense blue light, mainly, through a unique transcription factor complex that activates its targets in a light-dependent manner. In Trichoderma atroviride, the BLR-1 and BLR-2 proteins constitute this complex, which triggers the light-dependent formation of asexual reproduction structures (conidia). We generated an ENVOY photoreceptor mutant and performed RNA-seq analyses in the mutants of this gene and in those of the BLR-1, CRY-1 and CRY-DASH photoreceptors in response to a pulse of low intensity blue light. Like in other filamentous fungi BLR-1 appears to play a central role in the regulation of blue-light responses. Phenotypic characterization of the Δenv-1 mutant showed that ENVOY functions as a growth and conidiation checkpoint, preventing exacerbated light responses. Similarly, we observed that CRY-1 and CRY-DASH contribute to the typical light-induced conidiation response. In the Δenv-1 mutant, we observed, at the transcriptomic level, a general induction of DNA metabolic processes and strong repression of central metabolism. An analysis of the expression level of DNA repair genes showed that they increase their expression in the absence of env-1. Consistently, photoreactivation experiments showed that Δenv-1 had increased DNA repair capacity. Our results indicate that light perception in T. atroviride is far more complex than originally thought.