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BACKGROUND
S. latifolia is a model organism for the study of sex chromosome evolution in plants. Its sex chromosomes include large regions in which recombination became gradually suppressed. The regions tend to expand over time resulting in the formation of evolutionary strata. Non-recombination and
The action of natural selection is expected to reduce the effective population size of a nonrecombining chromosome, and this is thought to be the chief factor leading to genetic degeneration of Y-chromosomes, which cease recombining during their evolution from ordinary chromosomes. Low effective
Most flowering plants are hermaphroditic, having flowers with both male and female parts. Less than 4% of plant species are dioecious (with individuals of separate sexes), and many of these species have chromosome-mediated sex determination. The taxonomic distribution of separate sexes and
The human Y--probably because of its nonrecombining nature--has lost 97% of its genes since X and Y chromosomes started to diverge [1, 2]. There are clear signs of degeneration in the Drosophila miranda neoY chromosome (an autosome fused to the Y chromosome), with neoY genes showing faster protein
The nonrecombining regions of animal Y chromosomes are known to undergo genetic degeneration, but previous work has failed to reveal large-scale gene degeneration on plant Y chromosomes. Here, we uncover rapid and extensive degeneration of Y-linked genes in a plant species, Silene latifolia, that
Sex chromosomes evolved many times independently in many different organisms [1]. According to the currently accepted model, X and Y chromosomes evolve from a pair of autosomes via a series of inversions leading to stepwise expansion of a nonrecombining region on the Y chromosome (NRY) and the
Silene latifolia is a dioecious plant with heteromorphic XY sex chromosomes. Previous studies of sex chromosome-linked genes have suggested a gradual divergence between the X-linked and the Y-linked genes in proportion to the distance from the pseudoautosomal region. However, such a comparison has
The dioecious plant Silene latifolia has both X and Y sex chromosomes. Male-specific random amplified polymorphic DNA (RAPD) fragments were analyzed to identify Y-chromosome-linked sequences. One of the RAPD fragments, MS4, was converted into a more reliable and reproducible sequence-tagged site
When Microbotryum lychnidis-dioicae infects a male Silene latifolia, M. lychnidis-dioicae smut spores develop in the pollen sac instead of pollen. In contrast, when M. lychnidis-dioicae infects a female S. latifolia, the female flowers become male-like, promoting stamen formation. However, it is
When inoculated with the dimorphic smut fungus Microbotryum violaceum (Pers.) G. Deml and Oberwinkler, the female flower of the dioecious plant Silene latifolia (Miller) E.H.L. Krause develops anther-like structures filled with spores instead of pollen grains. Using natural scanning electron
Silene latifolia is dioecious, yet rare hermaphrodites have been found, and such natural mutants can provide valuable insight into genetic mechanisms. Here, we describe a hermaphrodite-inducing mutation that is almost certainly localized to the gynoecium-suppression region of the Y chromosome in S.
The most prominent feature of Y chromosomes is that they do not recombine and are usually genetically degenerate, containing only a few genes. White campion Silene latifolia has evolved sex chromosomes relatively recently, probably within the last 10-15 million years. Perhaps due to its recent
Dioecious white campion Silene latifolia has sex chromosomal sex determination, with homogametic (XX) females and heterogametic (XY) males. This species has become popular in studies of sex chromosome evolution. However, the lack of genes isolated from the X and Y chromosomes of this species is a
Silene latifolia is a model organism to study evolutionary young heteromorphic sex chromosome evolution in plants. Previous research indicates a Y-allele gene degeneration and a dosage compensation system already operating. Here, we propose an epigenetic approach based on analysis of several histone
Sex chromosomes stop recombining and accumulate differences over time. In particular, genes on the chromosome restricted to the heterogametic sex degenerate and become non-functional. Here, we investigated whether or not the degeneration of a plant Y chromosome was sufficient to cause ovules