New species with B chromosomes discovered since 1980

Jones, Neil

doi:10.1007/s13237-017-0215-6

Cited by 34 publications

(25 citation statements)

References 188 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The B chromosomes (B s ) were initially described in 1907 as additional elements to the standard karyotype in species of the Metapodius genus (Hemiptera) [ 1 ]. The number of eukaryotic species with B s were estimated from 1685 [ 2 ] in 1980 to more than 2828 [ 3 ] in 2017. Among Orthopteran species, B s were described in 191 species, which constitutes 11,9% of studied species [ 4 ].…”

Section: Introductionmentioning

confidence: 99%

B Chromosomes in Grasshoppers: Different Origins and Pathways to the Modern Bs

Jetybayev

Bugrov

Dzuybenko

et al. 2018

Genes

View full text Add to dashboard Cite

B chromosomes (Bs) were described in most taxa of eukaryotes and in around 11.9% of studied Orthopteran species. In some grasshopper species, their evolution has led to many B chromosome morphotypes. We studied the Bs in nine species (Nocaracris tardus, Nocaracris cyanipes, Aeropus sibiricus, Chorthippus jacobsoni, Chorthippus apricarius, Bryodema gebleri, Asiotmethis heptapotamicus songoricus, Podisma sapporensis, and Eyprepocnemis plorans), analyzing their possible origin and further development. The studied Bs consisted of C-positive or C-positive and C-negative regions. Analyzing new data and considering current hypotheses, we suggest that Bs in grasshoppers could arise through different mechanisms and from different chromosomes of the main set. We gave our special attention to the Bs with C-negative regions and suggest a new hypothesis of B chromosome formation from large or medium autosomes. This hypothesis includes dissemination of repetitive sequences and development of intercalary heterochromatic blocks in euchromatic chromosome arm followed by deletion of euchromatic regions located between them. The hypothesis is based on the findings of the Eyprepocnemis plorans specimens with autosome containing numerous intercalary repeat clusters, analysis of C-positive Bs in Eyprepocnemis plorans and Podisma sapporensis containing intercalary and terminal C-negative regions, and development of heterochromatic neo-Y chromosome in some Pamphagidae grasshoppers.

show abstract

Section: Introductionmentioning

confidence: 99%

B Chromosomes in Grasshoppers: Different Origins and Pathways to the Modern Bs

Jetybayev

Bugrov

Dzuybenko

et al. 2018

Genes

View full text Add to dashboard Cite

show abstract

“…Despite the fact that B chromosomes add significant amounts of genetic material to the genome, B chromosomes have rarely been associated with novel phenotypes, the most frequent exception being an effect on fertility [2,6,20,21,22]. With a limited list of known B-specific sequences and few or no visible phenotypes beyond drive, the prevalent view has been that B chromosomes carry few genes [14,23].…”

Section: Introductionmentioning

confidence: 99%

Genomic Characterization of a B Chromosome in Lake Malawi Cichlid Fishes

Clark

Conte

Kocher

2018

Preprint

View full text Add to dashboard Cite

B chromosomes (Bs) were discovered a century ago, and since then most studies have focused on describing their distribution and abundance using traditional cytogenetics. Only recently have attempts been made to understand their structure and evolution at the level of DNA sequence. Many questions regarding the origin, structure, function and evolution of B chromosomes remain unanswered. Here we identify B chromosome sequences from several species of cichlid fish from Lake Malawi by examining the ratios of DNA sequence coverage in individuals with and without B chromosomes. We examine the efficiency of this method, and compare results using both Illumina and PacBio sequence data. The B chromosome sequences detected in 13 individuals from 7 species were compared to assess the rates of sequence replacement. B-specific sequence common to at least 12 of the 13 datasets are identified as the “Core” B chromosome. The location of B sequence homologs throughout the genome provides further support for theories of B chromosome evolution. Finally, we identified candidate genes located on the B chromosome which may regulate the segregation and maintenance of the B chromosome.

show abstract

“…These properties are essentially the way that we define B chromosomes today, with the additional facts that they are usually smaller than the basic A chromosome set (As) and often heterochromatic. They can be detected at mitosis and meiosis (Figure ), and are now known in close to two thousand species of plants and animals (Jones, ; Jones & Rees, ). A number of review papers deal with the story of B chromosomes (Table ), including the most recent discoveries that they may contain transcribed genes.…”

Section: Introduction—what Are B Chromosomes?mentioning

confidence: 99%

Are B chromosomes useful for crop improvement?

Jones

Ruban

2019

Plants People Planet

Self Cite

View full text Add to dashboard Cite

Societal Impact Statement Ensuring the sustainable production of food within the context of an increasing world population is a huge challenge facing humankind. Here we review the existence of additional, non‐essential chromosomes, known as B chromosomes, and consider their potential usefulness for crop improvement. These enigmatic chromosomes have long fascinated scientists and although their origin and function in plants is somewhat obscure, new research is beginning to shed light on these mysterious chromosomes. This work suggests that B chromosomes may be useful for crop improvement, particularly in grasses, where they show promise as a mechanism to introduce new genes, which could potentially help us to produce more efficient crops. Summary The question of the usefulness of supernumerary B chromosomes (Bs) has long fascinated cytogeneticists. Since their discovery in 1907 thousands of species with Bs have been discovered, but their function in the genetics system remains enigmatic, from their origin, evolution, and adaptive significance, as well as their molecular structure and organization. New research is beginning to answer some of these tantalizing questions. Here, we summarize the known data and conclude that Bs are potentially useful, but only in a few known cases, especially in the grasses, and notably in terms of their engineering as plant artificial chromosomes (mini‐chromosomes) to carry whole suites of transgenes outside of, and free from interference with, the normal genome.

show abstract

New species with B chromosomes discovered since 1980

Cited by 34 publications

References 188 publications

B Chromosomes in Grasshoppers: Different Origins and Pathways to the Modern Bs

B Chromosomes in Grasshoppers: Different Origins and Pathways to the Modern Bs

Genomic Characterization of a B Chromosome in Lake Malawi Cichlid Fishes

Are B chromosomes useful for crop improvement?

Contact Info

Product

Resources

About