Project description:Large-scale identification of transcripts with large cross-genotype differences in abundance provides a genome-wide approach to identify natural variation in gene function. Transcript profiling was performed in 20 Arabidopsis accessions at dusk, dawn and after a 6h extension of the night. Individual genes with a high variance in transcript abundances across accessions were identified by inspection at each individual time point and by ANOVA across all three time points. Up to 40% of genes show significant changes in transcript abundance between accessions, with over-enrichment for biotic resistance, including pathogenesis resistance proteins and glucosinolate metabolism, cell wall modification, minor carbohydrate metabolism, amino acid degradation, brassinosteroid metabolism, redox and abiotic stress and underrepresentation of photosynthesis, DNA synthesis, RNA processing, regulation of transcription, protein synthesis and protein targeting. Some functional classes were enriched at all three time points. Genes related to carbon starvation-responses were enriched specifically at dawn, when their transcript abundance varied independently of carbohydrate levels, pointing to genetic variation in the sensitivity with which low carbon is sensed. Cross-accession correlation networks were generated at each time point to identify sets of genes whose transcripts show coordinated change in abundance between accessions. A cluster that was highly enriched for cold-response genes was found at dusk and after an extension of the night. Another cluster found at all three time points was highly enriched for glucosinolate biosynthesis, and correlated with glucosinolate content. We conclude that genes involved in stress and defense related processes show especially large and coordinated natural variation in transcript abundance.
Project description:Genetic interactions between SUPPRESSOR OF GENE SILENCING3 and ABSCISIC ACID HYPERSENSITIVE1/CAP-BINDING PROTEIN80 affecting fertilization, embryogenesis, germination, flowering time, and powdery mildew resistance