Evolutionary history of Silene latifolia sex chromosomes revealed by genetic mapping of four genes.
The sex chromosomes of dioecious white campion, Silene latifolia (Caryophyllaceae), are of relatively recent origin (10-20 million years), providing a unique opportunity to trace the origin and evolution of sex chromosomes in this genus by comparing closely related Silene species with and without sex chromosomes. Here I demonstrate that four genes that are X-linked in S. latifolia are also linked in nondioecious S. vulgaris, which is consistent with Ohno's (1967) hypothesis that sex chromosomes evolve from a single pair of autosomes. I also report a genetic map for four S. latifolia X-linked genes, SlX1, DD44X, SlX4, and a new X-linked gene SlssX, which encodes spermidine synthase. The order of the genes on the S. latifolia X chromosome and divergence between the homologous X- and Y-linked copies of these genes supports the "evolutionary strata" model, with at least three consecutive expansions of the nonrecombining region on the Y chromosome (NRY) in this plant species.
Filatov
Dmitry A
DA
School of Biosciences, University of Birmingham, Edgbaston, UK. d.filatov@bham.ac.uk
D002874:Chromosome Mapping; D003433:Crosses, Genetic; D017931:DNA Primers / Q000235:genetics; D018744:DNA, Plant; D019143:Evolution, Molecular; D017343:Genes, Plant; D008957:Models, Genetic; D010944:Plants / Q000235:genetics; D016133:Polymerase Chain Reaction; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA; D012730:Sex Chromosomes; D029751:Silene / Q000235:genetics*; D014960:X Chromosome; D014998:Y Chromosome
D017931:DNA Primers; D018744:DNA, Plant