TY  - JOUR
A1  - Hojsgaard, Diego
A1  - Schartl, Manfred
T1  - Skipping sex: A nonrecombinant genomic assemblage of complementary reproductive modules
JF  - BioEssays
N2  - The unusual occurrence and developmental diversity of asexual eukaryotes remain a puzzle. De novo formation of a functioning asexual genome requires a unique assembly of sets of genes or gene states to disrupt cellular mechanisms of meiosis and gametogenesis, and to affect discrete components of sexuality and produce clonal or hemiclonal offspring. We highlight two usually overlooked but essential conditions to understand the molecular nature of clonal organisms, that is, a nonrecombinant genomic assemblage retaining modifiers of the sexual program, and a complementation between altered reproductive components. These subtle conditions are the basis for physiologically viable and genetically balanced transitions between generations. Genomic and developmental evidence from asexual animals and plants indicates the lack of complementation of molecular changes in the sexual reproductive program is likely the main cause of asexuals' rarity, and can provide an explanatory frame for the developmental diversity and lability of developmental patterns in some asexuals as well as for the discordant time to extinction estimations.
KW  - amphimixis
KW  - apomixis
KW  - automixis
KW  - gynogenesis
KW  - hybridogenesis
KW  - parthenogenesis
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225818
VL  - 43
IS  - 1
ER  - 
TY  - JOUR
A1  - Schmid, Michael
A1  - Evans, Ben J.
A1  - Bogart, James P.
T1  - Polyploidy in Amphibia
JF  - Cytogenetic and Genome Research
N2  - This review summarizes the current status of the known extant genuine polyploid anuran and urodelan species, as well as spontaneously originated and/or experimentally produced amphibian polyploids. The mechanisms by which polyploids can originate, the meiotic pairing configurations, the diploidization processes operating in polyploid genomes, the phenomenon of hybridogenesis, and the relationship between polyploidization and sex chromosome evolution are discussed. The polyploid systems in some important amphibian taxa are described in more detail.
KW  - allopolyploidy
KW  - Anura
KW  - autopolyploidy
KW  - diploidization
KW  - hybridogenesis
KW  - polyploidization
KW  - sex chromosome evolution
KW  - Urodela
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-196730
SN  - 1424-8581
SN  - 1424-859X
N1  - This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.
VL  - 145
IS  - 3-4
ER  -