Project description:<p>Genome-wide association studies (GWAS) identified thousands of genetic loci associated with complex plant traits, including many traits of agronomical importance. However, functional interpretation of GWAS results remains challenging because of large candidate regions due to linkage disequilibrium. High-throughput omics technologies, such as genomics, transcriptomics, proteomics, and metabolomics open new avenues for integrative systems biological analyses and help to nominate systems information supported (prime) candidate genes. In the present study, we capitalize on a diverse canola population with spring-type 477 lines which was previously analysed by high-throughput phenotyping (Knoch et al., 2020), and by RNA sequencing and metabolite profiling for multi-omics-based hybrid performance prediction (Knoch et al., 2021). We deepened the phenotypic data analysis, now providing 123 time-resolved image-based traits, to gain insight into the complex relations during early vegetative growth and re-analysed the transcriptome data based on the latest Darmor-bzh v10 genome assembly (Rousseau-Gueutin et al., 2020). Genome-wide association testing revealed 61,298 robust quantitative trait loci (QTL) including 187 metabolite-QTL, 56,814 expression-QTL, and 4,297 phenotypic QTL, many clustered in pronounced hotspots. Combining information about QTL colocalisation across omics layers and correlations between omics features allowed us to discover prime candidate genes for metabolic and vegetative growth variation. Prioritized candidate genes for early biomass accumulation include A06p05760.1_BnaDAR (PIAL1), A10p16280.1_BnaDAR, C07p48260.1_BnaDAR (PRL1), and C07p48510.1_BnaDAR (CLPR4). Moreover, we observed unequal effects of the Brassica A and C subgenomes on early biomass production.</p><p><br></p>
Project description:Many crop species have complex genomes, making the conventional pathway to associating molecular markers with trait variation, which includes genome sequencing, both expensive and time-consuming. We used a streamlined approach to rapidly develop a genomics platform for hexaploid wheat based on the inferred order of expressed sequences. This involved assembly of the transcriptomes for the progenitor genomes of bread wheat, the development of a genetic linkage map comprising 9495 mapped transcriptome-based SNP markers, use of this map to rearrange the genome sequence of Brachypodium distachyon into pseudomolecules representative of the genome organization of wheat and sequence similarity-based mapping onto this resource of the transcriptome assemblies. To demonstrate that this approximation of gene order in wheat is appropriate to underpin association genetics analysis, we undertook Associative Transcriptomics for straw biomass traits, identifying associations and even candidate genes for height, weight and width.
Project description:The evolution of maize yields under drought is of particular concern in the context of climate change and human population growth. To better understand the mechanisms associated with the genetic polymorphisms underlying the variations of traits related to drought tolerance, we used a systems genetics approach integrating high-throughput phenotypic, proteomics and genomics data acquired on 254 maize hybrids grown under two watering conditions. We show that the genetic architecture of protein abundances depends on protein function and that water deficit strongly remodeled the proteome and induced a reprogramming of the genetic control of the abundances of proteins involved in drought and stress response. These findings bring several lines of evidence supporting candidate genes at many loci and provide novel insight into the molecular mechanisms of drought tolerance.
Project description:Western commercial pig breeds have been intensively selected, resulting in a sizeable, rapid, and efficient accretion of muscle but a reduction in meat quality. When compared with Western commercial pig breeds, Chinese indigenous pig breeds exhibited slower growth rates and reduced lean meat content but superior perceived meat quality. To study the factors that determine meat quality, we examined piglets of one Western commercial breed (Yorkshire) and one Chinese indigenous breed (Wannanhua) and sequenced the longissimus dorsi muscle using RNA-sequencing (RNA-seq). We analyzed their transcriptomes, focusing on identifying candidate genes that may influence porcine muscle growth, meat quality and adipose deposition. Gene ontology functional enrichment and pathway enrichment analyses identified differentially expressed genes primarily associated with glycolytic metabolism, biological processes of muscle development and signaling pathways related to fatty acid metabolism, growth and carcass traits. This finding suggests that the differentially expressed genes may play important roles in determining meat quality traits. Quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) confirmed the differential expression of twelve selected differentially expressed genes. This study identified a number of novel candidate genes for porcine meat quality and carcass traits that merit further investigation to elucidate the molecular mechanisms responsible for muscle growth and fat deposition.
Project description:Floral nectar proteins (nectarins) are mainly enzymes and play important roles in inhibiting microbial growth in nectar and tailoring nectar chemistry before or after secretory. Nectar proteomes are usually small, but only very few plant species have had their nectar proteomes thoroughly investigated. Nectarins from Nicotiana tabacum (NT) were separated using two-dimensional gel electrophoresis, and then analyzed using mass spectrometry. Glycoproteins were isolated from raw NT nectar, separated by SDS-PAGE, and identified by mass spectrometry. All eight identified nectarins and four invertase genes’ expression were analysed by qPCR. Sugars composition, total sugar concentration, protein content, polyphenol content and hydrogen peroxide content were compared at different time intervals in extracted nectar and nectar in situ after secretion. Totally, eight nectarins were detected in NT nectar in which only two are glycoproteins, beta-xylosidase and a protein with unknown function. All of the eight nectarin genes expression was not nectary-specific and not synchronous along with the nectary development. After secretion, NT nectar in flower tube changed from sucrose–rich to hexose-rich type even though no free invertase or its activity was detected in NT nectar. No sugar composition changes observed in extracted nectar after incubating at 30 ℃ up to 48 hours in plastic tubes. Our results indicate that nectar post-secretory changes could be a complex process and tissue closely contact with nectar might function in it.
2019-08-20 | PXD011658 | Pride
Project description:Identifying Candidate resistance genes for Cassava Brown Streak Virus
Project description:Cultivated carrot (Daucus carota L. ssp. sativus) was domesticated from wild carrot (Daucus carota L. ssp. carota) with radical different traits. The aim of this study was to compare the root transcriptomes between cultivated and wild carrots for SNP discovery, inferring domestication process, and identifying domestication genes. Six cultivated carrots representing main European carrot root types and five wild carrot populations from widely dispersed sites were used. The root transcriptomes were sequenced with multiplexing paried-end sequencing in Illumina Genome Analyzer IIx.
Project description:Many flowering plants attract pollinators by offering a reward of floral nectar. Remarkably, the molecular events involved in the development of nectaries, the organs that produce nectar, as well as the synthesis and secretion of nectar itself, are poorly understood. Indeed, to date, no genes have been shown to directly affect the de novo production or quality of floral nectar. To address this gap in knowledge, the ATH1 Affymetrix GeneChip array was used to systematically investigate the Arabidopsis nectary transcriptome to identify genes and pathways potentially involved in nectar production. In this study, we identified a large number of genes differentially expressed between secretory lateral nectaries and non-secretory median nectary tissues, as well as between mature lateral nectaries (post-anthessis) and immature lateral nectary tissue (pre-anthesis).