Project description:Integrated metabolomic and transcriptomic analyses reveal different anthocyanin biosynthetic pathways in Fragaria nilgerrensis and Fragaria pentaphylla
Project description:Breeding day-neutral strawberry (Fragaria x ananassa Duchesne) is pivotal to extend fruit-bearing season and increase the efficiency of production. However, genetic improvement of day-neutrality by the means of molecular marker technologies remains slow due to genome complexity of octoploid strawberry. This study employs an innovative approach by integrating the Subtracted Diversity Array (SDA) technology and Bulked Segregant Analysis (BSA) to facilitate the identification of molecular markers associated with day-neutrality in octoploid strawberry. A Fragaria Discovery Panel (FDP) containing 287 features specific to strawberry genome was constructed as a platform for rapid screening of DNA polymorphism between one short day (SD) strawberry DNA bulk and three day-neutral (DN) bulks varrying in flowering strength. Differential array hybridisation patterns between the DN and SD bulks revealed a novel molecular marker, FaP2E11, closely linked to CYTOKININ OXIDASE 1 (CKX1) gene possibly involved in promoting flowering under non-inductive condition. Interestingly, a 12 bp deletion was observed within the FaP2E11 sequence cloned from SD genotypes but not DN genotypes. As cytokinin is required to induce flowering, this result indicates that full sequence of FaP2E11 and the sequence with deletion are allelic variants linked to the low enzyme activity CKX1 and the wild type alleles, respectively.
Project description:Plants remember what they have experienced and are thereby able to confront repeated stresses more promptly and strongly. A subset of genes showed increased transcript levels under drought stress conditions, followed by a return to basal levels during recovery (watered) states, and then displayed elevated levels again under subsequent drought conditions. To screen for a set of drought stress memory genes in soybean (Glycine max L. cv. Daepoong), we designed a 180K DNA chip comprising 60-bp probes synthesized in situ to examine 55,588 loci. Through microarray analysis using the DNA chip, we identified 2,165 and 2,385 genes with more than 4-fold increases or decreases in transcript levels, respectively, under initial (first) drought stress conditions, when compared with the non-treated control. The transcript levels of the genes returned to basal levels during recovery (watered) states, then 677 and 987 genes displayed more than 16-fold elevated or reduced levels, respectively, under subsequent (second) drought conditions, when compared to the non-treated control. Gene Ontology analysis classified the drought stress memory genes into several functional categories, including those involved in trehalose biosynthesis and drought tolerance responses. We selected a number of drought stress memory genes encoding various transcription factors, protein phosphatase 2Cs, and late embryogenesis abundant proteins, and confirmed the microarray data by quantitative reverse-transcription real-time PCR. Upon repeated watering and subsequent (third) drought treatment, the elevated levels of the drought stress memory gene transcripts were propagated into newly developed second leaves, although at reduced levels when compared to the second drought treatment on the first leaves.
