scholarly journals Reconstruction of ancestral chromosome architecture and gene repertoire reveals principles of genome evolution in a model yeast genus

2016 ◽  
Vol 26 (7) ◽  
pp. 918-932 ◽  
Author(s):  
Nikolaos Vakirlis ◽  
Véronique Sarilar ◽  
Guénola Drillon ◽  
Aubin Fleiss ◽  
Nicolas Agier ◽  
...  
Keyword(s):  
Genome Evolution ◽  
Gene Repertoire ◽  
Yeast Genus ◽  
Chromosome Architecture ◽  
Ancestral Chromosome

scholarly journals Limited DNA repair gene repertoire in Ascomycete yeast revealed by comparative genomics

2019 ◽  
Author(s):  
Shira Milo ◽  
Reut Harari Misgav ◽  
Einat Hazkani-Covo ◽  
Shay Covo
Keyword(s):  
Dna Repair ◽  
Genome Evolution ◽  
Genomic Analysis ◽  
Comparative Genomic ◽  
Gene Repertoire ◽  
Dna Repair Genes ◽  
Repair Gene ◽  
Brettanomyces Bruxellensis ◽  
Dna Repair Gene ◽  
Repair Genes

Abstract Ascomycota is the largest phylogenetic group of fungi that includes species important to human health and wellbeing. DNA repair is important for fungal survival and genome evolution. Here, we describe a detailed comparative genomic analysis of DNA repair genes in Ascomycota. We determined the DNA repair gene repertoire in Taphrinomycotina, Saccharomycotina, Leotiomycetes, Sordariomycetes, Dothideomycetes, and Eurotiomycetes. The subphyla of yeasts, Saccharomycotina and Taphrinomycotina, have a smaller DNA repair gene repertoire comparing to Pezizomycotina. Some genes were absent from most, if not all, yeast species. To study the conservation of these genes in Pezizomycotina, we used the GLOOME algorithm that provides the expectations of gain or loss of genes given the tree topology. Genes that were absent from most of the species of Taphrinomycotina or Saccharomycotina showed lower conservation in Pezizomycotina. This suggests that the absence of some DNA repair in yeasts is not random; genes with a tendency to be lost in other classes are missing. We ranked the conservation of DNA repair genes in Ascomycota. We found that Rad51 and its paralogs were less conserved than other recombinational proteins, suggesting that there is a redundancy between Rad51 and its paralogs, at least in some species. Finally, based on the repertoire of UV repair genes, we found conditions that differentially kill the wine pathogen Brettanomyces bruxellensis and not Saccharomyces cerevisiae. In summary, our analysis provides testable hypotheses to the role of DNA repair proteins in the genome evolution of Ascomycota.

Evolution of Eukaryotic Gene Repertoire and Gene Structure: Discovering the Unexpected Dynamics of Genome Evolution

2003 ◽  
Vol 68 (0) ◽  
pp. 293-302 ◽  
Author(s):  
I.B. ROGOZIN ◽  
V.N. BABENKO ◽  
N.D. FEDOROVA ◽  
J. D. JACKSON ◽  
A.R. JACOBS ◽  
...  
Keyword(s):  
Genome Evolution ◽  
Gene Structure ◽  
Gene Repertoire ◽  
Eukaryotic Gene

scholarly journals Transposon-mediated telomere destabilization: a driver of genome evolution in the blast fungus

2020 ◽  
Author(s):  
Mostafa Rahnama ◽  
Olga Novikova ◽  
John H Starnes ◽  
Shouan Zhang ◽  
Li Chen ◽  
...  
Keyword(s):  
Genome Evolution ◽  
Magnaporthe Oryzae ◽  
Tandem Repeats ◽  
Collateral Damage ◽  
High Frequencies ◽  
Chromosome Architecture ◽  
Molecular Alterations ◽  
Rdna Sequences ◽  
And Function ◽  
Independent Expansion

Abstract The fungus Magnaporthe oryzae causes devastating diseases of crops, including rice and wheat, and in various grasses. Strains from ryegrasses have highly unstable chromosome ends that undergo frequent rearrangements, and this has been associated with the presence of retrotransposons (Magnaporthe oryzae Telomeric Retrotransposons—MoTeRs) inserted in the telomeres. The objective of the present study was to determine the mechanisms by which MoTeRs promote telomere instability. Targeted cloning, mapping, and sequencing of parental and novel telomeric restriction fragments (TRFs), along with MinION sequencing of genomic DNA allowed us to document the precise molecular alterations underlying 109 newly-formed TRFs. These included truncations of subterminal rDNA sequences; acquisition of MoTeR insertions by ‘plain’ telomeres; insertion of the MAGGY retrotransposons into MoTeR arrays; MoTeR-independent expansion and contraction of subtelomeric tandem repeats; and a variety of rearrangements initiated through breaks in interstitial telomere tracts that are generated during MoTeR integration. Overall, we estimate that alterations occurred in approximately sixty percent of chromosomes (one in three telomeres) analyzed. Most importantly, we describe an entirely new mechanism by which transposons can promote genomic alterations at exceptionally high frequencies, and in a manner that can promote genome evolution while minimizing collateral damage to overall chromosome architecture and function.

Nuclear Envelope Dynamics During Mitosis

1988 ◽  
Vol 46 ◽  
pp. 224-225
Author(s):  
Brian Burke
Keyword(s):  
Nuclear Envelope ◽  
Membrane Vesicles ◽  
Nuclear Pore ◽  
Nuclear Pore Complexes ◽  
Animal Cells ◽  
Interphase Chromosome ◽  
Lamin B ◽  
Chromosome Architecture ◽  
Complex Membrane ◽  
Pore Complexes

The nuclear envelope is a complex membrane structure that forms the boundary of the nuclear compartment in eukaryotes. It regulates the passage of macromolecules between the two compartments and may be important for organizing interphase chromosome architecture. In interphase animal cells it forms a remarkably stable structure consisting of a double membrane ouerlying a protein meshwork or lamina and penetrated by nuclear pore complexes. The latter form the channels for nucleocytoplasmic exchange of macromolecules, At the onset of mitosis, however, it rapidly disassembles, the membranes fragment to yield small vesicles and the lamina, which is composed of predominantly three polypeptides, lamins R, B and C (MW approx. 74, 68 and 65 kDa respectiuely), breaks down. Lamins B and C are dispersed as monomers throughout the mitotic cytoplasm, while lamin B remains associated with the nuclear membrane vesicles.

Sign in / Sign up

Export Citation Format

Share Document