Special Issue "Evolution, Composition and Regulation of Supernumerary B Chromosomes"
Deadline for manuscript submissions: 31 August 2018
Dr. Vladimir Trifonov
Supernumerary B chromosomes are dispensable genetic elements found in thousands of species of plants and animals, and some fungi. Since their discovery, more than a century ago, they have been a source of puzzlement, as they only occur in some members of a population and are absent from others. When they do occur, they are often harmful, and in the absence of 'selfishness', based on mechanisms of mitotic and meiotic drive, there appears to be no obvious reasons for their existence. Cytogeneticists have long wrestled with questions about the biological existence of these enigmatic B chromosomes, including their lack of any adaptive properties, apparent absence of functional genes, their origin, sequence organization and co-evolution as nuclear parasites. Emerging new technologies are now enabling researchers to step up a gear, to look enthusiastically beyond the previous limits of the horizon, and to uncover the secrets of these 'silent' elements. Detailed investigations into their DNA composition, transcriptional activity and effects on the host transcriptome profile are beginning to uncover a wealth of new information. Contributing authors come from across a wide range of species, and different systems, and their thematic output will give a broad view and a significant step forward to understanding this perplexing biological story.Prof. Andreas Houben
Prof. Neil Jones
Prof. Cesar Martins
Dr. Vladimir Trifonov
Manuscript Submission Information
Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.
Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Genes is an international peer-reviewed open access monthly journal published by MDPI.
Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.
- accessory chromosome
- B chromosome
- supernumerary chromosome
- selfish DNA
- chromosome drive
- gene silencing
- Muller’s ratchet
- mutation accumulation
- repetitive DNA
- next generation sequencing
- chromosome thripsis
The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.
Tentative title: Structural and functional analysis of transposable elements focusing on B chromosomes of the cichlid fish Astatotilapia latifasciata
Authors: Rafael LB COAN and Cesar MARTINS
Authors affiliation: Sao Paulo State University (UNESP), Institute of Biosciences, Department of Morphology, Botucatu, SP, Brazil.
Tentative abstract: B chromosomes (B) are supernumerary elements found in many taxonomic groups. Most B chromosomes are rich in heterochromatin and composed of abundant repetitive sequences, especially transposable elements (TE). Bs origin is generally linked to the A chromosome complement (A). The first report of a B chromosome in African cichlids was on Astatotilapia latifasciata, which can harbor 0, 1 or 2 B chromosomes. Classical cytogenetics studies found high TE content on the species B chromosome. In this study, we aim to understand TE composition and expression on A. latifasciata genome and its relation to the B chromosome. We use bioinformatics analysis to find TE organization on the genome, and also their composition on the B chromosome. Bioinformatics findings were validated by fluorescent in situ hybridization (FISH) and real-time PCR (qPCR). A latifasciata has a TE content similar to other cichlid fishes and several expanded elements on its B chromosome. With RNA sequencing data (RNA-seq) we showed that all major TE classes are transcribed in brain, muscle and male/female gonads. The evaluation of TE expression between B- and B+ individuals showed that few elements have differential expression among groups and expanded B elements were not highly transcribed. Putative silencing mechanisms may the acting on the B chromosome of A. latifasciata to prevent adverse consequences of repeat transcription and mobilization on the genome.
Tentative title: Transmission and drive involving parasitic B chromosomes
Author: Neil Jones
Tentative abstract: B chromosomes are enigmatic additional elements in the genomes of thousands of species of plants, animals and fungi. How do these non-essential, harmful and parasitic chromosomes maintain their presence in their hosts, making demands on all the essential functions of their host genomes? The answer seems to be that they have mechanisms of drive which enable them to enhance their transmission rates by various processes of non-Mendelian inheritance. These processes are reviewed and discussed.