Biology subjects

Poidevin, L.

Publications and source records attributed to Poidevin, L..

3 recordsLinked to original sources

bioRxiv2021

Comparative transcriptome analysis of noble crayfish and marbled crayfish immune response to Aphanomyces astaci challenges

Introduction of invasive North American crayfish species and their pathogen Aphanomyces astaci has significantly contributed to the decline of European freshwater crayfish populations. In this study, noble crayfish, a susceptible native European species, and marbled crayfish, an invasive disease-resistant species, were challenged with haplogroup A (low virulence) and haplogroup B (high virulence) strain of A. astaci. Hepatopancreatic tissue was isolated 3 and 21 days post-challenge. Our results revealed strong up-regulation in expression levels of the prophenoloxidase cascade immune-related genes in the haplogroup B challenged noble crayfish 3 days post-challenge. In the marbled crayfish, we observed an up-regulation of immune system relevant genes (DSCAM, AP, ALFs, CTLs and hemocyanin) 3 days post-challenge. This response highlights the marbled crayfish capability of building the immune tolerance. Furthermore, we successfully characterised several novel immune related gene groups in both crayfish species, contributing to our current understanding of crayfish immune related genes landscape. Graphical abstracta) Study species noble crayfish (Astacus astacus) in purple and marbled crayfish (Procambarus virginalis) in green challenged with the pathogen Aphanomyces astaci haplogroup A (Hap A) strain of low virulence and haplogroup B (Hap B) strain of high virulence. b) Sampling scheme of the infection experiment: 5 individuals were taken from the experiment three- and 21-days post-challenge. From each individual, a hepatopancreas sample was taken, followed by RNA isolation and sequencing. c) De novo transcriptome assembly and annotation were conducted for each species. d) Differential gene expression analysis revealed the distinct immune response in the noble crayfish 3 days post-challenge with the Hap B strain of A. astaci and marbled crayfish 3 days post-challenge with the Hap A strain of A. astaci. Immune related DEGs were not present in either species 21 days post-challenge with A. astaci. e) Noble crayfish challenged with the Hap B strain of A. astaci were acutely infected and ultimately moribund, while the A. astaci Hap A challenged marbled crayfish showed high resistance to the pathogen, resulting infected without any mortality. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=103 SRC="FIGDIR/small/445163v1_ufig1.gif" ALT="Figure 1"> View larger version (53K): org.highwire.dtl.DTLVardef@d1830aorg.highwire.dtl.DTLVardef@f2196forg.highwire.dtl.DTLVardef@63c8f2org.highwire.dtl.DTLVardef@11da1b6_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

bioRxiv2020

Characterization of novel pollen-expressed transcripts reveals their potential roles in pollen heat stress response in Arabidopsis thaliana.

The male gametophyte is the most heat-sensitive of all plant tissues. In recent years, long noncoding RNAs (lncRNAs) have emerged as important components of cellular regulatory networks involved in most biological processes, including response to stress. While examining RNAseq datasets of developing and germinating Arabidopsis thaliana pollen exposed to heat stress (HS), we identified 66 novel and 246 recently-annotated intergenic expressed loci (XLOCs) of unknown function, with the majority encoding lncRNAs. Comparison to HS in cauline leaves and other RNAseq experiments, indicated 74% of the 312 XLOCs are pollen-specific, and at least 42% are HS-responsive. Phylogenetic analysis revealed 96% of the genes evolved recently in Brassicaceae. We found that 50 genes are putative targets of microRNAs, and that 30% of the XLOCs contain small open reading frames (ORFs) with homology to protein sequences. Finally, RNAseq of ribosome-protected RNA fragments together with predictions of periodic footprint of the ribosome P-sites indicated that 23 of these ORFs are likely to be translated. Our findings indicate that many of the 312 unknown genes might be functional, and play significant role in pollen biology, including the HS response.

plant biology↗

bioRxiv2020

Transcriptome and translatome changes in germinated pollen under heat stress uncover roles of transporter genes involved in pollen tube growth.

Plant reproduction is one key biological process very sensitive to heat stress and, as a consequence, enhanced global warming poses serious threats to food security worldwide. In this work we have used a high-resolution ribosome profiling technology to study how heat affects both the transcriptome and the translatome of Arabidopsis thaliana pollen germinated in vitro. Overall, a high correlation between transcriptional and translational responses to high temperature was found, but specific regulations at the translational level were also present. We show that bona fide heat shock genes are induced by high temperature indicating that in vitro germinated pollen is a suitable system to understand the molecular basis of heat responses. Concurrently heat induced significant down-regulation of key membrane transporters required for pollen tube growth, thus uncovering heat-sensitive targets. We also found that a large subset of the heat-repressed transporters is specifically up-regulated, in a coordinated manner, with canonical heat-shock genes in pollen tubes grown in vitro and semi in vivo, based on published transcriptomes from Arabidopsis thaliana. Ribosome footprints were also detected in gene sequences annotated as non-coding, highlighting the potential for novel translatable genes and translational dynamics.

plant biology↗