Project description:Perennial plants, like fruit trees grown in temperate regions, are characterized by bud dormancy, a rest state that protects the bud from cold during winter. At the same time, these plants have developed a requirement for winter chill for correct flowering. However, winters are becoming increasingly warm in temperate regions, resulting in dramatic effects on the flowering output and therefore crop yield. A compound that successfully compensates for missing winter chill is hydrogen cyanamide, which has been used to synchronize and advance flowering time in a range of commercially important fruit crops. Hydrogen cyanamide also represents a unique tool for researchers to study controlled endodormancy release. Here, we treated dormant sweet cherry flower buds with hydrogen cyanamide, sampling flower buds at different time points after treatment. RNAseq revealed more than 6,000 hydrogen cyanamide-responsive genes. In accordance with these results, hydrogen cyanamide treatment increased the levels of jasmonoyl-isoleucine (JA-Ile) and the cytokinins trans-zeatin riboside (tZR), dihydrozeatin (DZ) and dihydrozeatin riboside (DZR). Furthermore, hydrogen cyanamide affected the expression of antioxidant- and cell wall loosening-associated transcripts. These results suggest a complex mechanism of action for hydrogen cyanamide-induced endodormancy release, including key roles for JA-Ile, zeatin-type cytokinins and hydrogen cyanide.
Project description:Optimised flowering time is an important trait ensuring successful plant adaptation and crop productivity. SOC1-like genes encode MADS transcription factors known to play important roles in flowering control in many plants. This includes the best characterised eudicot model Arabidopsis thaliana (Arabidopsis) where SOC1 promotes flowering and functions as a floral integrator gene integrating signals from different flowering time regulatory pathways. Medicago truncatula (Medicago) is a temperate reference legume with strong genomic and genetic resources used to study flowering pathways in legumes. Interestingly, despite responding to the similar floral-inductive cues of extended cold (vernalisation) followed by warm long days, as winter annual Arabidopsis, Medicago lacks FLC and CO which are key regulators of flowering in Arabidopsis. Unlike Arabidopsis with one SOC1 gene, multiple gene duplication events have given rise to three MtSOC1 paralogs within the Medicago genus in legumes; one Fabaceae group A SOC1 gene, MtSOC1a, and two tandemly-repeated Fabaceae group B SOC1 genes, MtSOC1b and MtSOC1c. Previously, we showed that MtSOC1a has unique functions in floral promotion in Medicago. The Mtsoc1a Tnt1 retroelement insertion single mutant showed moderately delayed flowering in long and short day photoperiods, with and without prior vernalization, compared with wild type. On the other hand, Mtsoc1b Tnt1 single mutants did not have altered flowering time or flower development, indicating that it was redundant in an otherwise wild type background. Here, we describe the generation of Mtsoc1 triple mutant plants by CRISPR-Cas9 gene editing. Two independent Mtsoc1 homozygous triple mutants were non-flowering and bushy in floral inductive VLD. Phenotyping and gene expression analyses by RNA-seq and RT-qPCR indicate that the Mtsoc1 triple mutants remain vegetative. Thus overall, the Mtsoc1 triple mutants are dramatically different from the single Mtsoc1a mutant and the Arabidopsis soc1 mutant; implicating multiple MtSOC1 genes in critical overlapping roles in the transition to flowering in Medicago.
Project description:The veins of leaves are a highly evolved vascular network that allows plants to grow large and complex. The patterning process leading to their formation involves the integration of several internal and external signals, such as plant hormone auxin. Here, we show that an evolutionarily conserved transcription factor controlling leaf vein growth in flowering plants VDOF1 is dependent on autophagy for its activity in Arabidopsis thaliana leaf, suggesting that this pathway might be required for proper vascular system development in leaf. Taken together, our data forms that during leaf vein patterning there is presents a network in which a module that links VDOF1-ATG8-ANT1-SCR-SHR factors integrates Space-time dimension to provide more vein density, which establish a precondition for C4 photosynthesis transition.
Project description:Abscisic acid (ABA) regulates seed and bud dormancy. We show by forward and reverse genetic analysis that the tomato transcription factor SlZFP2 is required for release of bud and seed dormancy through negative regulation of ABA biosynthesis. We also demonstrated that ABA promotes growth and represses flowering in tomato both through transcriptional control on the florigen-encoding gene SINGLE FLOWER TRUSS (SFT) in tomato. To gain further insight on transcriptome changes by overexpresion of HA-SlZFP2, we sequenced two lines of p35S:HA-SlZFP2 in LA1589 background and their nontransgenic siblings on Illumina Hiseq2000 platform. Two homozygous transgenic lines 103 and 104 showing very similar phenotypes in flowering and branching were chosen for profiling gene expression via RNA sequencing. Their respective nontransgenic siblings were served as controls (103N and 104N).
Project description:Using WGBS we investigated blood DNA methylation profiles of Cooinda the Alpine dingo and determined putative regulatory elements (unmethylated regions, UMRs, and lowly methylated regions, LMRs).
Project description:Abscisic acid (ABA) regulates seed and bud dormancy. We show by forward and reverse genetic analysis that the tomato transcription factor SlZFP2 is required for release of bud and seed dormancy through negative regulation of ABA biosynthesis. We also demonstrated that ABA promotes growth and represses flowering in tomato both through transcriptional control on the florigen-encoding gene SINGLE FLOWER TRUSS (SFT) in tomato. To gain further insight on transcriptome changes by overexpresion of HA-SlZFP2, we sequenced two lines of p35S:HA-SlZFP2 in LA1589 background and their nontransgenic siblings on Illumina Hiseq2000 platform.
Project description:Gene expression profile of flower buds at stage 13, open flowers at stage 14 and siliques at stages 15/16, according to Smyth et al., 1990) of ABAP1 overexpressing (ABAP1OE) plants compared to wild type flower buds, open flowers and siliques (Col-0) using a a whole-genome oligonucleotide array (Operon) (platform accession number accession number GPL1077). ABAP1 is a negative regulator of the cell cycle that binds to transcription factors and represses their target gene expression, including pre-replication complex genes. All experiments were performed in triplicate.
Project description:We sequenced mRNA from late vegetative meristems of tomato mutant TERMINARING FLOWER as well as the wild type progenitor to see genome-wide expression changes affected by the mutation. Meristems from multiple plants at the same developmental stages were collected for both mutants and wild types. The meristems were pooled together for mRNA extractions. Two biological replicates for each genotypes were prepared for mRNA extraction and sequencing library construction.