Cytogenetics and Evolution

Atanassova, B.; Georgiev, Hristo

doi:10.1201/b10744-4

Cited by 13 publications

(16 citation statements)

References 137 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results are similar to observations made earlier using light microscopic observations of pachytene meiotic chromosomes from certain tomato F 1 hybrids [Khush and Rick, 1963;Rick and Yoder, 1988]. Since synapsis usually starts near telomeres in tomato [Stack and Anderson, 1986], the extensive, regular formation of SC in euchromatin is consistent with the high level of gene colinearity (homology) observed among members of the tomato clade [Rick, 1979;Tanksley et al, 1992;Chetelat and Ji, 2007]. The presence of RNs in numbers similar to those observed in cherry tomato also is consistent with balanced segregation of chromosomes at anaphase I and the generally high levels of fertility of the F 1 hybrids [Rick, 1979;Rick and Yoder, 1988;Sherman and Stack, 1992].…”

Section: Discussionsupporting

confidence: 78%

“…Members of the tomato clade have long been considered to have stable genomes in which speciation has occurred primarily by genic change and not large-scale chromosomal alterations [Rick, 1979;Chetelat and Ji, 2007;Moyle, 2008]. However, our results show that significant changes in chromosome structure have occurred among the different species.…”

Section: Discussioncontrasting

confidence: 53%

“…Although easily visible as mismatched kinetochores in SC spreads, pericentric inversions with breakpoints that occur in recombination-suppressed regions with relatively fewer genes would be expected to have little, if any, effect on genetic linkage maps and would be unlikely to show significant deviation from the marker colinearity usually observed in tomato ! wild species hybrids [Frary et al, 2005;Chetelat and Ji, 2007]. (2) Observed differences in genome sizes (DNA amounts) between species in the tomato clade could provide a second explanation for mismatched kinetochores.…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

Structural Differences in Chromosomes Distinguish Species in the Tomato Clade

Anderson

Covey

Larsen

et al. 2010

Cytogenet Genome Res

View full text Add to dashboard Cite

The tomato clade of Solanaceae is composed of 12 species that are all diploid with the same chromosome number and morphology. Species in the tomato clade are considered to have evolved primarily by genic changes rather than large-scale chromosomal rearrangements because pachytene chromosomes in F₁ hybrids synapse normally along their lengths and linkage maps of intra- and inter-specific hybrids are co-linear. However, small inversions have been reported between tomato and some of its wild relatives. Therefore, we reevaluated 5 F₁ hybrids using high-resolution, electron microscopic examination of pachytene chromosome (= synaptonemal complex) spreads to determine whether any minor structural changes had occurred among species in the tomato clade, which were not easily visible using light microscopic analysis of conventional chromosome squashes. Our study revealed a number of unexpected synaptic configurations such as mismatched kinetochores, inversion loops and reciprocal translocations. Most of these structural differences were in or close to heterochromatin that has comparatively few genes and little recombination, so they would be expected to have little effect on the evident colinearity of linkage maps, especially in euchromatin. However, these results demonstrate that substantial changes in chromosome structure have occurred among species within the tomato clade.

show abstract

Section: Discussionsupporting

confidence: 78%

Section: Discussioncontrasting

confidence: 53%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Structural Differences in Chromosomes Distinguish Species in the Tomato Clade

Anderson

Covey

Larsen

et al. 2010

Cytogenet Genome Res

View full text Add to dashboard Cite

show abstract

“…1). All members of the clade are closely related diploids (2 n = 24) (Peralta and Spooner 2001; Nesbitt and Tanksley 2002) that share a high degree of genomic synteny (Chetelat and Ji 2007), and are to some degree intercrossable (Rick 1979). Recent taxonomic revision indicates that Lycopersicon is nested within Solanum and renames Lycopersicon species accordingly (Peralta and Spooner 2001).…”

Section: Biological Diversitymentioning

confidence: 99%

Ecological and Evolutionary Genomics in the Wild Tomatoes (Solanum Sect. Lycopersicon)

Moyle¹

2008

Evolution

104

126

View full text Add to dashboard Cite

The plant group Solanum section Lycopersicon (the clade containing the domesticated tomato and its wild relatives) is ideal for integrating genomic tools and approaches into ecological and evolutionary research. Wild species within Lycopersicon span broad morphological, physiological, life history, mating system, and biochemical variation, and are separated by substantial, but incomplete postmating reproductive barriers, making this an ideal system for genetic analyses of these traits. This ecological and evolutionary diversity is matched by many logistical advantages, including extensive historical occurrence records for all species in the group, publicly available germplasm for hundreds of known wild accessions, demonstrated experimental tractability, and extensive genetic, genomic, and functional tools and information from the tomato research community. Here I introduce the numerous advantages of this system for Ecological and Evolutionary Functional Genomics (EEFG), and outline several ecological and evolutionary phenotypes and questions that can be fruitfully tackled in this system. These include biotic and abiotic adaptation, reproductive trait evolution, and the genetic basis of speciation. With the modest enhancement of some research strengths, this system is poised to join the best of our currently available model EEFG systems. K E Y W O R D S :Abiotic, adaptation, natural selection, reproductive isolation, speciation, tomato. Feder and Mitchell-Olds 2003) aims to provide a detailed mechanistic understanding of the genetic basis of natural biological diversity, and the evolutionary processes responsible for the creation and maintenance of this diversity. To do this requires both an understanding of the mechanistic basis of phenotypic variation (i.e., an ability to connect genotype to phenotype), and an understanding of the mechanistic basis of adaptation (i.e., an ability to connect natural phenotypic variation with fitness consequences in the wild). In this sense, EEFG encompasses many of the aims of classical "ecological and evolutionary genetics" (e.g., Stebbins 1950; Dobzhansky 1970) albeit with more explicitly molecular, and correspondingly more ambitious, goals. The use of genomic tools to address ecological and evolutionary questions is already attracting accelerating interest (e.g., Ecological and Evolutionary Functional Genomics (EEFG-

show abstract

“…Furthermore, linkage maps of intra‐ and inter‐specific hybrids were found to be largely colinear (Pertuzé et al. , 2002; Chetelat and Ji, 2007; Moyle, 2008). Both similarity in chromosome morphology and marker colinearity supported the notion that Solanum species have evolved primarily by genic change rather than by large‐scale chromosomal rearrangements.…”

Section: Introductionmentioning

confidence: 99%

Structural homology in the Solanaceae: analysis of genomic regions in support of synteny studies in tomato, potato and pepper

et al. 2012

View full text Add to dashboard Cite

SUMMARYWe have analysed the structural homology in euchromatin regions of tomato, potato and pepper with special attention for the long arm of chromosome 2 (2L). Molecular organization and colinear junctions were delineated using multi-color BAC FISH analysis and comparative sequence alignment. We found large-scale rearrangements including inversions and segmental translocations that were not reported in previous comparative studies. Some of the structural rearrangements are specific for the tomato clade, and differentiate tomato from potato, pepper and other Solanaceous species. Although local gene vicinity is largely preserved, there are many small-scale synteny perturbations. Gene adjacency in the aligned segments was frequently disrupted for 47% of the ortholog pairs as a result of gene and LTR retrotransposon insertions, and occasionally by single gene inversions and translocations. Our data also suggests that long distance intrachromosomal rearrangements and local gene rearrangements have evolved frequently during speciation in the Solanum genus, and that small changes are more prevalent than large-scale differences. The occurrence of sonata and harbinger transposable elements and other repeats near or at junction breaks is considered in the light of repeat-mediated rearrangements and a reconstruction scenario for an ancestral 2L topology is discussed.

show abstract

Cytogenetics and Evolution

Cited by 13 publications

References 137 publications

Structural Differences in Chromosomes Distinguish Species in the Tomato Clade

Structural Differences in Chromosomes Distinguish Species in the Tomato Clade

Ecological and Evolutionary Genomics in the Wild Tomatoes (Solanum Sect. Lycopersicon)

Structural homology in the Solanaceae: analysis of genomic regions in support of synteny studies in tomato, potato and pepper

Contact Info

Product

Resources

About