Plant Physiology Preview
Published on August 24, 2007; 10.1104/pp.107.104380
Received June 26, 2007
Accepted August 13, 2007
Ancestral Chromosomal Blocks Are Triplicated in Brassiceae Species with Varying Chromosome Number and Genome Size
Martin A. Lysak *, Kwok Cheung , Michaela Kitschke , and Petr Bures
Department of Functional Genomics and Proteomics, Masaryk University, Kamenice 5, CZ – 625 00, Brno, Czech Republic; Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AB, UK; Department of Botany and Zoology, Masaryk University, Kotlárská 2, CZ – 611 37, Brno, Czech Republic
* Corresponding author; email: lysak{at}sci.muni.cz.
The paleopolyploid character of genomes of the economically important genus Brassica and closely related species (tribe Brassiceae) is still fairly controversial. Here we report on the comparative painting analysis of the block F of the crucifer Ancestral Karyotype (AK; n=8), consisting of 24 conserved genomic blocks, in ten species traditionally treated as members of the tribe Brassiceae. Three homeologous copies of block F were identified per haploid chromosome complement in Brassiceae species with 2n=14, 18, 20, 32, and 36. In high polyploid (n 30) species Crambe maritima (2n=60), C. cordifolia (2n=120) and Vella pseudocytisus (2n=68), six, twelve, and six copies of the analyzed block have been revealed, respectively. Homeologous regions resembled the ancestral structure of block F within the AK or were altered by inversions and/or translocations. In two species of the subtribe Zillineae, two of the three homeologous regions were combined via a reciprocal translocation onto one chromosome. Altogether these findings provide compelling evidence of an ancient hexaploidization event and corresponding whole-genome triplication shared by the tribe Brassiceae. No direct relationship between chromosome number and genome size variation (1.2-2.5 pg/2C) variation has been found in Brassiceae species with 2n=14-36. Only two homeologous copies of block F suggest a whole-genome duplication but not the triplication event in Orychophragmus violaceus (2n=24), and confirm a phylogenetic position of this species outside the tribe Brassiceae. Chromosome duplication detected in Orychophragmus as well as chromosome rearrangements shared by Zillineae species demonstrate the usefulness of comparative cytogenetics for elucidation of phylogenetic relationships.
This article has been cited by other articles:
|
|
|
|
 
X.-H. Ge, J. Wang, and Z.-Y. Li
Different genome-specific chromosome stabilities in synthetic Brassica allohexaploids revealed by wide crosses with Orychophragmus
Ann. Bot.,
July 1, 2009;
104(1):
19 - 31.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
Y. Tu, J. Sun, X. Ge, and Z. Li
Chromosome elimination, addition and introgression in intertribal partial hybrids between Brassica rapa and Isatis indigotica
Ann. Bot.,
May 1, 2009;
103(7):
1039 - 1048.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
L. Peruzzi, I. J. Leitch, and K.F. Caparelli
Chromosome diversity and evolution in Liliaceae
Ann. Bot.,
February 1, 2009;
103(3):
459 - 475.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. A. Lysak, M. A. Koch, J. M. Beaulieu, A. Meister, and I. J. Leitch
The Dynamic Ups and Downs of Genome Size Evolution in Brassicaceae
Mol. Biol. Evol.,
January 1, 2009;
26(1):
85 - 98.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
X. Tang, D. Szinay, C. Lang, M. S. Ramanna, E. A. G. van der Vossen, E. Datema, R. K. Lankhorst, J. de Boer, S. A. Peters, C. Bachem, et al.
Cross-Species Bacterial Artificial Chromosome-Fluorescence in Situ Hybridization Painting of the Tomato and Potato Chromosome 6 Reveals Undescribed Chromosomal Rearrangements
Genetics,
November 1, 2008;
180(3):
1319 - 1328.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
T. Mandakova and M. A. Lysak
Chromosomal Phylogeny and Karyotype Evolution in x=7 Crucifer Species (Brassicaceae)
PLANT CELL,
October 1, 2008;
20(10):
2559 - 2570.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
