Results 21 to 30 of about 2,455 (197)
Improved Basic Cytogenetics Challenges Holocentricity of Butterfly Chromosomes [PDF]
Cytogenetic and Genome Research, 2022 Mitotic chromosomes of butterflies, which look like dots or short filaments in most published data, are generally considered to lack localised centromeres and thus to be holokinetic. This particularity, observed in a number of other invertebrates, is associated with meiotic particularities known as “inverted meiosis,” in which the first division is ...
Bernard Dutrillaux +5 more
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Chiasmatic and achiasmatic inverted meiosis of plants with holocentric chromosomes. [PDF]
Nat Commun, 2014 AbstractMeiosis is a specialized cell division in sexually reproducing organisms before gamete formation. Following DNA replication, the canonical sequence in species with monocentric chromosomes is characterized by reductional segregation of homologous chromosomes during the first and equational segregation of sister chromatids during the second ...
Cabral G +4 more
europepmc +6 more sources
Holocentric chromosomes in animals and plants: what do we know about these points outside the curve?
Evidência, 2023 Usually, members of the Eukarya domain have kinetochores grouped at a single point, characterizing monocentric chromosomes. However, in some taxa the protein apparatus that composes the kinetochore is distributed continuously or discretely along the ...
Gabriela Corrêa Morais +2 more
doaj +1 more source
Meiosis Progression and Recombination in Holocentric Plants: What Is Known?
Frontiers in Plant Science, 2021 Differently from the common monocentric organization of eukaryotic chromosomes, the so-called holocentric chromosomes present many centromeric regions along their length.
Paulo G. Hofstatter +3 more
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Holocentric chromosomes: from tolerance to fragmentation to colonization of the land. [PDF]
Ann Bot, 2018 The dispersed occurrence of holocentric chromosomes across eukaryotes implies they are adaptive, but the conditions under which they confer an advantage over monocentric chromosomes remain unclear. Due to their extended kinetochore and the attachment of spindle microtubules along their entire length, holocentric chromosomes tolerate fragmentation ...
Zedek F, Bureš P.
europepmc +4 more sources
Zipping up the Synaptonemal Complex: Pathways to Homologous Chromosome Synapsis. [PDF]
BioessaysThe synaptonemal complex (SC) is a conserved protein structure that assembles between homologous chromosomes during meiosis. Here, we review pathways promoting homologous synapsis across model organisms, examining coordination with homolog pairing and recombination, spatiotemporal regulation of SC assembly, and the conserved molecular modules coupling ...
Gold AL, Kim Y.
europepmc +2 more sources
Unlocking holocentric chromosomes: new perspectives from comparative and functional genomics? [PDF]
Curr Genomics, 2012 The presence of chromosomes with diffuse centromeres (holocentric chromosomes) has been reported in several taxa since more than fifty years, but a full understanding of their origin is still lacking. Comparative and functional genomics are nowadays furnishing new data to better understand holocentric chromosome evolution thus opening new perspectives ...
Mandrioli M, Manicardi GC.
europepmc +4 more sources
A holocentric twist to chromosomal speciation?
Trends in Ecology & Evolution, 2022 Chromosomal rearrangements trigger speciation by acting as barriers to gene flow. However, the underlying theory was developed with monocentric chromosomes in mind. Holocentric chromosomes, lacking a centromeric region, have repeatedly evolved and account for a significant fraction of extant biodiversity.
Kay Lucek +2 more
openaire +6 more sources
A satellite explosion in the genome of holocentric nematodes. [PDF]
PLoS ONE, 2013 Centromere sequences in the genome are associated with the formation of kinetochores, where spindle microtubules grow in mitosis. Centromere sequences usually have long tandem repeats (satellites).
Juan A Subirana, Xavier Messeguer
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Centromere diversity and its evolutionary impacts on plant karyotypes and plant reproduction. [PDF]
New PhytolSummary Karyotype changes are a formidable evolutionary force by directly impacting cross‐incompatibility, gene dosage, genetic linkage, chromosome segregation, and meiotic recombination landscape. These changes often arise spontaneously and are commonly detected within plant lineages, even between closely related accessions.
Steckenborn S, Marques A.
europepmc +2 more sources