Accumulation of chloroplast DNA sequences on the Y chromosome of Silene latifolia.
Silene latifolia is a model dioecious plant with heteromorphic sex chromosomes. The Y chromosome is the largest in this species. Theoretical models propose an accumulation of repetitive DNA sequences in non-recombining parts of the Y chromosome. In this study, we isolated a BAC7H5 clone preferentially hybridizing to the Y chromosome of S. latifolia. Sequence analysis revealed that this BAC7H5 contains part of the chloroplast genome, indicating that these chloroplast sequences have accumulated on the Y chromosome and also may contribute to its large size. We constructed Y chromosome- and X chromosome-specific libraries and screened them to find Y- and/or X-linked copies of chloroplast sequences. Sequence analysis revealed higher divergence of a non-genic region of the chloroplast sequences located on the Y chromosome while genic regions tested showed only very low (max 0.9%) divergence from their chloroplast homologues.
Kejnovsky
Eduard
E
Laboratory of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, CZ-612 65, Brno, Czech Republic. kejnovsk@ibp.cz
Kubat
Zdenek
Z
Hobza
Roman
R
Lengerova
Martina
M
Sato
Shusei
S
Tabata
Satoshi
S
Fukui
Kiichi
K
Matsunaga
Sachihiro
S
Vyskot
Boris
B
D001483:Base Sequence; D022202:Chromosomes, Artificial, Bacterial / Q000235:genetics; D032461:Chromosomes, Plant / Q000235:genetics*; D017931:DNA Primers / Q000235:genetics; D018742:DNA, Chloroplast / Q000235:genetics*; D019143:Evolution, Molecular; D017404:In Situ Hybridization, Fluorescence; D008957:Models, Genetic; D008969:Molecular Sequence Data; D012689:Sequence Homology, Nucleic Acid; D029751:Silene / Q000235:genetics*
D017931:DNA Primers; D018742:DNA, Chloroplast