Untitled

Abstract

A comprehensive survey of the molecular-cytogenetic features of the Vicia faba chromosome complement (2n = 12) is given. It includes previous as well as new original data. Various Giemsa, restriction endonuclease and fluorochrome banding patterns, azacytidine-mediated segment extension, replication patterns, lateral A/T asymmetry and sequence localization data for tandemly arranged simple sequence repeats, dispersed repeats and coding sequences as well as histone acetylation patterns are considered. This allows not only to distinguish and characterize telomeres, subtelomeres, centromeres and the NOR, but also the structure of the 5S rRNA gene loci and two main types of interstitial heterochromatin. Additionally, it offers physical landmarks within euchromatic areas. Thus, the field bean genome, exemplified by the reconstructed karyotype ACB, belongs to the cytogenetically best investigated plant genomes.

Distribution of 45S rDNA sites in chromosomes of plants: Structural and evolutionary implications

“…In Amaryllidaceae, Asteraceae, Cycadaceae, Ginkgoaceae, Poaceae, Podocarpaceae and Solanaceae the sites were predominantly terminal, while in Asparagaceae, Cupressaceae, Fabaceae, Pinaceae and Zamiaceae, the most common position was proximal to interstitial (Figure 5). Within some families, such as Solanaceae, the distribution of sites was similar in most genera (Additional file 2: Figure S3), while in others, such as Fabaceae, the sites were predominantly or exclusively proximal in some genera, such as Arachis [61-64] and Lens [65], and mainly terminal in others, as Phaseolus [66,67] and Vicia [68-71] (Additional file 2: Figure S3). The stability of sites in Solanaceae may be related to the karyotype stability of this group [72] although conservation in chromosome number and morphology is not enough to ensure stability of rDNA site position as observed in other taxa with apparently stable karyotype, as Citrus [73] and Pinus [74].…”

Enhancing faba bean (Vicia faba L.) genome resources

“…This is rather surprising given that faba bean is diploid (2 n =12 chromosomes). Chromosome fusion is known to have occurred during faba bean evolution (Fuchs et al , 1998). As with other large genomes, genome size expansion can be accounted for by repetitive DNA sequences that consist of different types of transposable elements.…”

Advancing Eucalyptus Genomics: Cytogenomics Reveals Conservation of Eucalyptus Genomes

“…Comparative cytogenomic analysis is important to understand species evolution through the assessment of genetic divergence between them using genome organization knowledge (Lipman et al, 2013 ; Cai et al, 2014 ). Techniques such as fluorochrome banding (chromomycin, Hoechst, and DAPI) and fluorescence in situ hybridization (FISH) are exceptional molecular cytogenetic tools to reveal phylogenetic relationships among species in several crops (Maluszynska and Heslop-Harrison, 1993 ; Fuchs et al, 1998 ; Hajdera et al, 2003 ; Srisuwan et al, 2006 ), but also in trees (Ribeiro et al, 2008 ). The constitutive heterochromatin (AT-rich or GC-rich DNA) and rRNA genes are the most widely used FISH markers (Siljak-Yakovlev et al, 2014 ), however modern molecular cytogenetic studies benefit from BAC libraries.…”