Cytogenetic evidence of nucleolar dominance in allotetraploid species of<i>Brachypodium</i>

Idziak, D.; Hasterok, Robert

doi:10.1139/g08-017

Cited by 30 publications

(34 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The smaller number of endosperm protein subunits shared by the 2n = 10 and 2n = 20 forms than between either of the above and the 2n = 30 forms corroborates the possible allopolyploidal origin of the 2n = 30 forms. Some authors have already proposed the classification of the different ploidy forms of B. distachyon as a different species (Hasterok et al 2004(Hasterok et al , 2006Idziak and Hasterok 2008). …”

Section: Discussionmentioning

confidence: 99%

“…The species of the genus Brachypodium have small chromosomes of variable number (x = 5, 7, 8, 9 or 10), making them unusual among the members of the Pooideae, which tend to have large chromosomes and base number of 7 (Shi et al 1993;Draper et al 2001;Hasterok et al 2004Hasterok et al , 2006Idziak and Hasterok 2008;Garvin et al 2008). Although ecotypes of B. distachyon with 10, 20 and 30 chromosomes have been described, some authors have indicated that these numbers do not represent a simple autopolyploid series (Robertson 1981).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Prolamin storage proteins and alloploidy in wild populations of the small grass Brachypodium distachyon (L.) P. Beauv.

et al. 2011

View full text Add to dashboard Cite

This paper reports the glutenin diversity of a collection of 23 wild populations of the grass Brachypodium distachyon collected in the Mediterranean and southern areas of the Iberian Peninsula. The plant material studied included the three different cytotypes of this species: 2n = 10, 2n = 20 and 2n = 30. A specific method of extraction was used to isolate the glutenin subunits from the caryopsis. Separation by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) showed them to correspond to wheat low-molecular-weight glutenin subunits (LMW-GS). Twenty-two LMW-GS-like were identified that showed great diversity within and between populations. All the populations investigated were polymorphic for the endosperm proteins studied. The 2n = 30 forms had the largest number of subunits; these were also more diverse than those of the 2n = 10 or 2n = 20 forms. The 2n = 10 forms, the most common in the higher, interior areas of the Iberian Peninsula, showed the smallest subunit variation. In fact, negative correlations were found between subunit diversity and altitude and longitude. In contrast, a positive correlation was detected with the annual average temperature and the indices of thermicity and Mediterraneity. The similarity between the populations was estimated using the Sorensen-Dice coefficient, calculated on the basis of the presence/absence of the 22 LMW-GS proteins. The similarity indices were used to produce a dendrogram using the unweighted pair-group method with arithmetic means (UPGMA). This method produced three main groups corresponding to the three cytotypes. An analysis was made of the possible correlation between eco-geographic and climatic factors and the gene diversity and polymorphism shown in the populations. The diversity correlated positively with the number of chromosomes (2n), annual mean temperature, index of thermicity and index of Mediterraneity. In contrast, diversity correlated negatively with altitude, longitude and index of precipitation during the summer. The number of chromosomes correlated negatively with altitude, longitude and precipitation during summer and positively with all the other climatic indices. These results are coherent with the fact that diploid forms were more common in areas of the interior and at higher altitude, where the climate is more extreme.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Prolamin storage proteins and alloploidy in wild populations of the small grass Brachypodium distachyon (L.) P. Beauv.

et al. 2011

View full text Add to dashboard Cite

show abstract

“…The plant also has small physical stature, short life cycle, and undemanding growth requirementsall of which make it amenable to high-throughput genetic screening. Therefore, Brachypodium could serve as a utility model system for various types of plant research Li et al 2008;Idziak and Hasterok 2008;Parker et al 2008;Spielmeyer et al 2008).…”

Section: Introductionmentioning

confidence: 99%

Structural characterization of Brachypodium genome and its syntenic relationship with rice and wheat

et al. 2009

View full text Add to dashboard Cite

Brachypodium distachyon (Brachypodium) has been recently recognized as an emerging model system for both comparative and functional genomics in grass species. In this study, 55,221 repeat masked Brachypodium BAC end sequences (BES) were used for comparative analysis against the 12 rice pseudomolecules. The analysis revealed that *26.4% of BES have significant matches with the rice genome and 82.4% of the matches were homologous to known genes. Further analysis of paired-end BES and *1.0 Mb sequences from nine selected BACs proved to be useful in revealing conserved regions and regions that have undergone considerable genomic changes. Differential gene amplification, insertions/deletions and inversions appeared to be the common evolutionary events that caused variations of microcolinearity at different orthologous genomic regions. It was found that *17% of genes in the two genomes are not colinear in the orthologous regions. Analysis of BAC sequences also revealed higher gene density (*9 kb/gene) and lower repeat DNA content (*13.1%) in Brachypodium when compared to the orthologous rice regions, consistent with the smaller size of the Brachypodium genome. The 119 annotated Brachypodium genes were BLASTN compared against the wheat EST database and deletion bin mapped wheat ESTs. About 77% of the genes retrieved significant matches in the EST database, while 9.2% matched to the bin mapped ESTs. In some cases, genes in single Brachypodium BACs matched to multiple ESTs that were mapped to the same deletion bins, suggesting that the Brachypodium genome will be useful for ordering wheat ESTs within the deletion bins and developing specific markers at targeted regions in the wheat genome.

show abstract

“…The presence of inactive rDNA sites was reported for many other plant species, e.g. Lupinus cosentinii [46], three diploid Brassica species of the U-triangle [51] and allotetraploid Brachypodium hybridum (ABR113) [52].…”

Section: Activity Of Rrna Genesmentioning

confidence: 99%

Intraspecific polymorphism of ribosomal DNA loci number and morphology in Brachypodium pinnatum and Brachypodium sylvaticum

Breda

Wolny

Hasterok

2012

Cellular and Molecular Biology Letters

Self Cite

View full text Add to dashboard Cite

Abbreviations used: Ag-NOR -silver-binding nucleolar organizer region; BAC -bacterial artificial chromosome; CMA+ -chromomycin A 3 positive bands; FISH -fluorescence in situ hybridisation; GISH -genomic in situ hybridisation; ITS -internal transcribed spacer; NOR -nucleolar organizer region; NTS -non-transcribed spacer; rDNA -ribosomal DNA Abstract: The genus Brachypodium has become the target of extensive cytomolecular studies since one of its representatives, B. distachyon, has been accepted as a model plant for temperate cereals and forage grasses. Recent preliminary studies suggested that intraspecific rDNA polymorphism can occur in at least two members of the genus, B. sylvaticum and B. pinnatum, so the aim of this study was to further analyse this phenomenon. FISH with 25S rDNA and 5S rDNA probes was performed on somatic metaphase chromosomes, supplemented by the silver staining technique which distinguishes transcriptionally active from inactive 18S-5.8S-25S rDNA loci. The number, size and chromosomal distribution of 5S rDNA loci were very constant: two loci were invariably observed in all studied diploid accessions of both species, while four 5S rDNA loci were present in the tetraploid B. pinnatum. In contrast to 5S rDNA loci, those of the 35S rDNA were more variable. Two or three loci were observed in the diploid B. pinnatum and four in tetraploid accessions. In chromosome complements of B. sylvaticum accessions from two to six 35S rDNA sites were detected. Regardless of total rDNA locus number, only two were transcriptionally active in diploid accessions of both species, while two or four were active in the tetraploid B. pinnatum. Additionally, the fluorescent CMA/DAPI banding method was used to identify the relation between rDNA sites and CMA+ bands. It was revealed that the number and chromosomal distribution of CMA+ bands are in congruence only with 35S rDNA loci which gave strong FISH signals.

show abstract

Cytogenetic evidence of nucleolar dominance in allotetraploid species ofBrachypodium

Cited by 30 publications

References 36 publications

Prolamin storage proteins and alloploidy in wild populations of the small grass Brachypodium distachyon (L.) P. Beauv.

Prolamin storage proteins and alloploidy in wild populations of the small grass Brachypodium distachyon (L.) P. Beauv.

Structural characterization of Brachypodium genome and its syntenic relationship with rice and wheat

Intraspecific polymorphism of ribosomal DNA loci number and morphology in Brachypodium pinnatum and Brachypodium sylvaticum

Contact Info

Product

Resources

About