Karyotyping and identifying all of the chromosomes of allopolyploid
Two almost identical clones, Aesp20 (997 nt) and Aesp21 (1001 nt), exhibited similarity to Ty3-gypsy of Brachypodium distachyon and 66-68% of homology at 88-89% coverage to the Ty3-gypsy VRN-B1 retrotransposon of allopolyploid
Based on the coassembly of homoeologs, SNiPloid compares either putative SNPs detected from an allopolyploid
to those obtained in its parental genomes, or putative SNPs derived from two allopolyploid
accessions to search for polymorphism.
(2005), using RAPD analysis, have proved that the origin of these species is allopolyploid
instead of autopolyploid.
The popular Gossypium hirsutum among the four species is an allopolyploid
(2n=4x=52; AD-genome) species that has originated from a single polyploidization event involving two diploid species; an A-genome maternal parent and a D-genome paternal parent approximately 0.5-2 mya (Cronn et al., 1999).
Though the causes of this persistence in mango mitosis is not clear, it was assumed to be associated with (a) the allopolyploid
nature of mango; (b) disturbance in the biosynthesis of some nucleolar component which stimulated the persistence; (c) disturbance in some pathway related to nucleolar disassembly; (d) failure in the phosphorilation machinery at RNA pol I, as mentioned before; and (e) requirement of some nucleolar proteins to the mango cell cycle progression compelling its persistence.
Parallel domestication, convergent evolution and duplicated gene recruitment in allopolyploid
Recent studies have shown that the allopolyploid
formation in triticale and wheat is accompanied by diverse genetic and epigenetic events (Ma et al., 2004; Feldman & Levy 2005; Ma & Gustafson, 2006, 2008).
The high proportion of bivalents at meiosis with the presence of some multivalents led Stebbins (1948) to propose an autoallopolyploid or segmental allopolyploid
Allopolyploidy speciation can result from somatic chromosome doubling into a diploid hybrid, followed by selfing to produce a tetraploid, as in Primula kewensis, an allopolyploid
that arose spontaneously in 1909 among cultivated diploid hybrids of P.
Polymorphism and concerted evolution in a tamdemly repeated gene family: 5S ribosomal DNA in diploid and allopolyploid
evolution coupled with diploidization may also facilitate the formation of new species capable of utilizing unique niches via plasticity and subsequent niche specialization.