Dataset Information

Cold-induced secondary dormancy and its regulatory mechanisms in Beta vulgaris.

ABSTRACT: The dynamic behaviour of seeds in soil seed banks depends on their ability to act as sophisticated environmental sensors to adjust their sensitivity thresholds for germination by dormancy mechanisms. Here we show that prolonged incubation of sugar beet fruits at low temperature (chilling at 5°C, generally known to release seed dormancy of many species) can induce secondary nondeep physiological dormancy of an apparently nondormant crop species. The physiological and biophysical mechanisms underpinning this cold-induced secondary dormancy include the chilling-induced accumulation of abscisic acid in the seeds, a reduction in the embryo growth potential and a block in weakening of the endosperm covering the embryonic root. Transcriptome analysis revealed distinct gene expression patterns in the different temperature regimes and upon secondary dormancy induction and maintenance. The chilling caused reduced expression of cell wall remodelling protein genes required for embryo cell elongation growth and endosperm weakening, as well as increased expression of seed maturation genes, such as for late embryogenesis abundant proteins. A model integrating the hormonal signalling and master regulator expression with the temperature-control of seed dormancy and maturation programmes is proposed. The revealed mechanisms of the cold-induced secondary dormancy are important for climate-smart agriculture and food security.

SUBMITTER: Hourston JE

PROVIDER: S-EPMC9305896 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Plants that exhibit secondary growth, such as trees, are a prominent feature of terrestrial ecosystems. Furthermore, secondary growth itself, particularly wood, has huge economic value. Despite the importance of secondary growth from both basic and applied science perspectives, little is known about the molecular mechanisms that underpin this facet of plant development. The proposed microarray experiments are designed to expand our knowledge of the regulation of secondary growth by combining the power of Arabidopsis genetics with complete transcriptome analysis. It is now well established that Arabidopsis can be grown under conditions that induce secondary growth in the hypocotyl, albeit small, wood. We have grown 8500 Arabidopsis plants of different genotypes under these conditions and will extract RNA from the developing vascular cambia of these plants to subject them to complete transcriptome analysis.The mutants that we have chosen for these analyses are all related to each other on the basis of the fact that they impact dormancy in either seeds or shoots (abi1, aba1, max4, axr1, AtMYB61 knockout, AtMYB50 knockout). The mutants themselves are the core group of mutants that are the focus of a three laboratory consortium, funded under the BBSRC Exploiting Genomics Initiative, to investigate the molecular basis of meristem dormancy in Arabidopsis. The other partners in the consortium are Dr. Ottoline Leyser (York) and Dr. Michael Holdsworth (IACR). While the Leyser and Holdsworth groups have investigated the impact of these mutations on transcriptome activity in shoot meristems and seeds respectively, our work focuses on the vascular cambium. Thus, this work will not only provide insights into the regulation of cambial function, but, when compared with the existing datasets from the Leyser and Holdworth labs, the work should also provide insights into the relationship between dormancy-impacted phenomena in different meristematic regions. Beyond this, the specific work on the cambium-specific regulation of genes in the MYB61KO will provide even greater insights into the functioning of this important resource allocation regulator, as it will build on a significant complete transcriptome dataset that is already available through GARNet. In total, the proposed analyses will generate important new data that builds on existing datasets, to provide an even more comprehensive understanding of gene function, and genetic networks, in an important biological and applied context. Please note that the sample numbers that we have provided below are meant to be the 'base' number for each biological condition (mutant, etc.), and that there will be independent TRIPLICATE biological replicates produced for each condition. (ie. A-1 to A-12). Keywords: strain_or_line_design; ecotype_analysis; mutant; insertion_mutant; gene_knock_out; tissue_organ_specificity;

Project description:The transition from vegetative growth to reproductive development is a complex process that requires an integrated response to multiple environmental cues and endogenous signals. In Arabidopsis thaliana, which has a facultative requirement for vernalization and long days, the genes of the autonomous pathway function as floral promoters by repressing the central repressor and vernalization-regulatory gene FLC. Environmental regulation by seasonal changes in daylength is under control of the photoperiod pathway and its key gene CO. The root and leaf crop species Beta vulgaris in the caryophyllid clade of core eudicots, which is only very distantly related to Arabidopsis, is an obligate long-day plant and includes forms with or without vernalization requirement. FLC and CO homologues with related functions in beet have been identified, but the presence of autonomous pathway genes which function in parallel to the vernalization and photoperiod pathways has not yet been reported. Here, this begins to be addressed by the identification and genetic mapping of full-length homologues of the RNA-regulatory gene FLK and the chromatin-regulatory genes FVE, LD, and LDL1. When overexpressed in A. thaliana, BvFLK accelerates bolting in the Col-0 background and fully complements the late-bolting phenotype of an flk mutant through repression of FLC. In contrast, complementation analysis of BvFVE1 and the presence of a putative paralogue in beet suggest evolutionary divergence of FVE homologues. It is further shown that BvFVE1, unlike FVE in Arabidopsis, is under circadian clock control. Together, the data provide first evidence for evolutionary conservation of components of the autonomous pathway in B. vulgaris, while also suggesting divergence or subfunctionalization of one gene. The results are likely to be of broader relevance because B. vulgaris expands the spectrum of evolutionarily diverse species which are subject to differential developmental and/or environmental regulation of floral transition.

Dataset Information

Cold-induced secondary dormancy and its regulatory mechanisms in Beta vulgaris.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets