Soukupova, M., Nevrtalova, E., Čížková, J., Vogel, I., Cegan, R., Hobza, R., Vyskot, B.
CYTOGENETIC AND GENOME RESEARCH
143:
96-103,
2014
Keywords:
Anther culture, Cytometry, Dihaploids, Genome sequencing, Haploid female plants, Sex chromosomes, Silene latifolia
Abstract:
Silene latifolia (or white campion) possesses a well-established
sex determination system with a dominant Y chromosome
in males (the mammalian type). The heteromorphic
sex chromosomes X and Y in S. latifolia largely stopped recombination;
thus, we can expect a gradual genetic degeneration
of the Y chromosome. It is well proven that neither
diploid nor polyploid S. latifolia sporophytes can survive
without at least one X, so the only life stage possessing the
Y as the sole sex chromosome is the male gametophyte (pollen
tube), while the female gametophyte seems to be X-dependent.
Previous studies on anther-derived plants of this
species showed that the obtained plants (largely haploid or
dihaploid) were phenotypically and cytologically female. In
this paper, we provide molecular evidence for the inviability
of plants lacking the X chromosome. Using sex-specific PCR
primers, we show that all plantlets and plants derived from
anther cultures are female. In studying anther-derived diploid
females by sequencing of X-linked markers, we demonstrate
that these plants are really homozygous dihaploids. A
haploid regenerant plant was sequenced (8× genome coverage)
using Illumina technology. Genome data are disposable
in the EMBL database as a standard for full genome and X
chromosome assembly in this model species. Homozygous
dihaploids were back-crossed with males to yield a progeny
useful for the study of the evolution of the Y chromosome.
Fulltext: contact IEB authors
IEB authors: Jana Čížková,
Roman Hobza
