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In higher plants, double fertilisation initiates seed development. One sperm cell fuses with the egg cell and gives rise to the embryo, the second sperm cell fuses with the central cell and gives rise to the endosperm. The endosperm develops as a syncytium with the gradual organisation of domains
BACKGROUND
The analysis of molecular variation within and between populations is crucial to establish strategies for conservation as well as to detect the footprint of spatially heterogeneous selection. The traditional estimator of genetic differentiation (F(ST)) has been shown to be misleading if
Simple de novo screens in Arabidopsis thaliana have previously identified mutants that affect endosperm development but viable-embryo mutants have not been identified. Our strategy to identify autonomous embryo development was to uncouple embryo and endosperm fertilisation. This involved a
Arabidopsis thaliana is a small cruciferous weed which grows naturally, mainly in Europe. Because of its qualities of small size, rapid growth, low chromosome number and self-fertilisation, I adapted it to aseptic growth in purified agar in sterile test-tubes. I found that it secreted various
BACKGROUND
New generation sequencing technology has allowed investigation of the small RNA populations of flowering plants at great depth. However, little is known about small RNAs in their reproductive cells, especially in post-meiotic cells of the gametophyte generation. Pollen - the male
Changes in breeding system are a regular evolutionary change in plants, as self-fertilisation is often advantageous, particularly for weedy and colonising species. The adoption of Arabidopsis thaliana as a plant model species has led to interest in how self-incompatibility was lost so that this
Sexual reproduction in flowering plants is distinct from that in animals since gametogenesis requires production of haploid spores, which divide and differentiate into specialised gametophyte structures. Anti-Silencing Function 1 (ASF1) is a histone H3/H4 chaperone involved in chromatin remodeling
BACKGROUND
Telomeres, as elaborate nucleo-protein complexes, ensure chromosomal stability. When impaired, the ends of linear chromosomes can be recognised by cellular repair mechanisms as double-strand DNA breaks and can be healed by non-homologous-end-joining activities to produce dicentric
The rsw1 mutant of Arabidopsis thaliana is mutated in a gene encoding a cellulose synthase catalytic subunit. Mutant seedlings produce almost as much cellulose as the wild type at 21 degrees C but only about half as much as the wild type at 31 degrees C. We used this conditional phenotype to
Pollen tube growth is essential for plant reproduction. Their rapid extension using polarized tip growth provides an exciting system for studying this specialized type of growth. Self-Incompatibility (SI) is a genetically controlled mechanism to prevent self-fertilisation. Mechanistically, one of
Rootcaps of the wild type (WT) and of a starchless, gravitropic mutant (TC7) of Arabidopsis thaliana L. were examined by electron microscopy to identify cellular polarities with respect to gravity. In columella cells, nuclei are located proximally, and the nuclear envelope is continuous with
The growth and geotropic movements of roots and hypocotyls of lettuce have been studied on board the Salyut 7 station in a stationary position and on the centrifuge at 0.01, 0.1 and 1 g. On the centrifuge at 0.1 and 0.01 g as well as under weightlessness, the final length of hypocotyls was by 8-16%
BACKGROUND
Seed development in the angiosperms requires the production of a female gametophyte (embryo sac) within the ovule. Many aspects of female reproductive development in cereal crops are yet to be described, largely due to the technical difficulty in obtaining phenotypic information at the
Fruits exhibit a vast array of different 3D shapes, from simple spheres and cylinders to more complex curved forms; however, the mechanism by which growth is oriented and coordinated to generate this diversity of forms is unclear. Here, we compare the growth patterns and orientations for two very
The role of resource availability in determining the incidence of masting has been widely studied, but how floral transition and initiation are regulated by the resource level is unclear. We tested the hypothesis that floral transition is stimulated by high resource availabiltiy in Fagus crenata