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Cruaud, C.

Publications and source records attributed to Cruaud, C..

39 records · Page 3Linked to original sources

Optimized real-time qPCR assays for detecting and quantifying the Fusarium and Microdochium species responsible for wheat head blight, as defined by MIQE guidelines

In order to better understand the Fusarium head blight disease, reliable real-time PCR assays for detection and quantification of fungal species belonging to the Fusarium and Microdochium genus are needed. Specific qPCR assays were developed for nine of those species. All criteria required for reproducing the assays are presented. The assays were species specific and allow quantification of at least 5 pg of fungal DNA and detection of 0.5 pg of fungal DNA per PCR reaction. Moreover we showed that the quantification performances of the tests were not altered in the presence of DNA of closely related species in the sample. The assays were tested on field samples and have been already used in greenhouse experiments.

molecular biology↗

De novo Clustering Nanopore Long Reads of Transcriptomics Data by Gene

Long-read sequencing currently provides sequences of several thousand base pairs. This allows to obtain complete transcripts, which offers an un-precedented vision of the cellular transcriptome.\n\nHowever the literature is lacking tools to cluster such data de novo, in particular for Oxford Nanopore Technologies reads, because of the inherent high error rate compared to short reads.\n\nOur goal is to process reads from whole transcriptome sequencing data accurately and without a reference genome in order to reliably group reads coming from the same gene. This de novo approach is therefore particularly suitable for non-model species, but can also serve as a useful pre-processing step to improve read mapping. Our contribution is both to propose a new algorithm adapted to clustering of reads by gene and a practical and free access tool that permits to scale the complete processing of eukaryotic transcriptomes.\n\nWe sequenced a mouse RNA sample using the MinION device, this dataset is used to compare our solution to other algorithms used in the context of biological clustering. We demonstrate its is better-suited for transcriptomics long reads. When a reference is available thus mapping possible, we show that it stands as an alternative method that predicts complementary clusters.

bioinformatics↗

High-quality de novo genome assembly of the Dekkera bruxellensis UMY321 yeast isolate using Nanopore MinION sequencing

Genetic variation in natural populations represents the raw material for phenotypic diversity. Species-wide characterization of genetic variants is crucial to have a deeper insight into the genotype-phenotype relationship. With the advent of new sequencing strategies and more recently the release of long-read sequencing platforms, it is now possible to explore the genetic diversity of any non-model organisms, representing a fundamental resource for biological research. In the frame of population genomic surveys, a first step is evidently to obtain the complete sequence and high quality assembly of a reference genome. Here, we completely sequenced and assembled a reference genome of the non-conventional Dekkera bruxellensis yeast. While this species is a major cause of wine spoilage, it paradoxically contributes to the specific flavor profile of some Belgium beers. In addition, an extreme karyotype variability is observed across natural isolates, highlighting that D. bruxellensis genome is very dynamic. The whole genome of the D. bruxellensis UMY321 isolate was sequenced using a combination of Nanopore long-read and Illumina short-read sequencing data. We generated the most complete and contiguous de novo assembly of D. bruxellensis to date and obtained a first glimpse into the genomic variability within this species by comparing the sequences of several isolates. This genome sequence is therefore of high value for population genomic surveys and represents a reference to study genome dynamic in this yeast species.

genomics↗