structural evolution
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Polyploidy, the result of whole-genome duplication (WGD), is a major driver of eukaryote evolution. Yet WGDs are hugely disruptive mutations, and we still lack a clear understanding of their fitness consequences. Here, we study whether WGDs result in greater diversity of genomic structural variants (SVs) and how they influence evolutionary dynamics in a plant genus, Cochlearia (Brassicaceae). By using long-read sequencing and a graph-based pangenome, we find both negative and positive interactions between WGDs and SVs. Masking of recessive mutations due to WGDs leads to a progressive accumulation of deleterious SVs across four ploidal levels (from diploids to octoploids), likely reducing the adaptive potential of polyploid populations. However, we also discover putative benefits arising from SV accumulation, as more ploidy-specific SVs harbor signals of local adaptation in polyploids than in diploids. Together, our results suggest that SVs play diverse and contrasting roles in the evolutionary trajectories of young polyploids.
1st ed. iv, 360 s.
Encephalization has many contexts and implications. On one hand, it is concerned with the transformation of eating habits, social relationships and communication, cognitive skills and the mind. Along with the increase in brain size on the other hand, encephalization is connected with the creation of more complex brain structures, namely in the cerebral cortex. It is imperative to inquire into the mechanisms which are linked with brain growth and to find out which of these mechanisms allow it and determine it. There exist a number of theories for understanding human brain evolution which originate from neurological sciences. These theories are the concept of radial units, minicolumns, mirror neurons, and neurocognitive networks. Over the course of evolution, it is evident that a whole range of changes have taken place in regards to heredity. These changes include new mutations of genes in the microcephalin complex, gene duplications, gene co-expression, and genomic imprinting. This complex study of the growth and reorganization of the brain and the functioning of hereditary factors and their external influences creates an opportunity to consider the implications of cultural evolution and cognitive faculties.
- MeSH
- biologická evoluce MeSH
- buněčná diferenciace MeSH
- duplikace genu MeSH
- lidé MeSH
- mozek anatomie a histologie MeSH
- regulace genové exprese MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
... Structure and Function of Biological Macromolecules 11 -- 2.1. The Nucleic Acids 13 -- 2.2. ... ... PRINCIPLES OF MOLECULAR SELECTION AND EVOLUTION -- 4. ... ... The Evolution of Hypercycles 228 -- 11.1. Self-Organization of Catalytic Hypercycles 229 -- 11.2. ... ... Evolution in the Test-Tube 257 -- 13.1. The Qp Replicase System 258 -- 13.2. ... ... Experimental Perspectives: An Evolution Machine 272 -- 14. ...
ix, 321 s. : il., tab., grafy ; 26 cm
"Darwinova teorie" je nepřesný pojem. Ve skutečnosti existuje pět základních teorií, jimiž Darwin evoluci vysvětloval. Kromě doslovné víry v Bibli přijetí Darwinovy teorie bránily a brání esencialismus a finalismus. Esencialismus je podkladem transmutacionismu a transformacionismu, překonaných teorií. Darwin nahradil esencialismus populačním myšlením. V průběhu první poloviny minulého století vznikla Moderní syntéza evoluční teorie – neodarwinismus. Současná evoluční genomika potvrdila tři ze šesti pilířů Moderní syntézy: - náhodné dědičné variace jako materiální podklad evoluce, - totožnost základních evolučních procesů v průběhu celé evoluce, a - posledního univerzálního společného předka. Zamítla však další tři: - přírodní výběr jako dominantní hnací sílu evoluce, - gradualismus, čili průběh evoluce v nepatrných krůčcích, a - jednoduchou původní představu stromu života.
"Darwin's theory" is an inaccurate term. In reality there are five basic Darwinian theories of evolution. In addition to rejecting biblical literalism Darwin's theories impeded and impede essentialism and finalism. Essentialism is a basis of transmutationism and transformationism, both antiquated theories. Darwin replaced essentialism by population thinking. So-called Modern synthesis (neo-Darwinism) evolved in the first half of the last century. Contemporary evolutionary genomics corroborates three of the six pillars of Modern synthesis: - random heritable variations, - uniformitarianism and - the last universal common ancestor, but refutes the next three pillars: natural selection as the main driving force of evolution, gradualism (evolution in „infinitesimally“ small steps), and a single large Tree of life.
- Klíčová slova
- současná evoluční genomika, šest teoretických pilířů moderní syntézy (neodarwinismus), Darwinových pět teorií,
- MeSH
- biologická evoluce MeSH
- genomika MeSH
- Publikační typ
- úvodníky MeSH
elektronický časopis
- MeSH
- biologická evoluce MeSH
- druhová specificita MeSH
- fylogeneze MeSH
- genetický kód MeSH
- sekvence nukleotidů MeSH
- Konspekt
- Obecná genetika. Obecná cytogenetika. Evoluce
- NLK Obory
- biologie
- genetika, lékařská genetika
- biologie
- NLK Publikační typ
- elektronické časopisy
Telomeres, which form the protective ends of eukaryotic chromosomes, are a ubiquitous and conserved structure of eukaryotic genomes but the basic structural unit of most telomeres, a repeated minisatellite motif with the general consensus sequence T(n)A(m)G(o), may vary between eukaryotic groups. Previous studies on several species of green algae revealed that this group exhibits at least two types of telomeric sequences, a presumably ancestral type shared with land plants (Arabidopsis type, TTTAGGG) and conserved in, for example, Ostreococcus and Chlorella species, and a novel type (Chlamydomonas type, TTTTAGGG) identified in Chlamydomonas reinhardtii. We have employed several methodical approaches to survey the diversity of telomeric sequences in a phylogenetically wide array of green algal species, focusing on the order Chlamydomonadales. Our results support the view that the Arabidopsis-type telomeric sequence is ancestral for green algae and has been conserved in most lineages, including Mamiellophyceae, Chlorodendrophyceae, Trebouxiophyceae, Sphaeropleales, and most Chlamydomonadales. However, within the Chlamydomonadales, at least two independent evolutionary changes to the Chlamydomonas type occurred, specifically in a subgroup of the Reinhardtinia clade (including C. reinhardtii and Volvox carteri) and in the Chloromonadinia clade. Furthermore, a complex structure of telomeric repeats, including a mix of the ancestral Arabidopsis-type motifs and derived motifs identical to the human-type telomeric repeats (TTAGGG), was found in the chlamydomonadalean clades Dunaliellinia and Stephanosphaeria. Our results indicate that telomere evolution in green algae, particularly in the order Chlamydomonadales, is far more dynamic and complex than thought before. General implications of our findings for the mode of telomere evolution are discussed.
- MeSH
- Chlorophyta genetika MeSH
- molekulární evoluce MeSH
- telomery genetika MeSH
- Volvocida genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Macmillan series in physical anthropology
XII, 322 s. : il. ; 24 cm
