Extraordinary tertiary constrictions of Tripsacum dactyloides chromosomes: implications for karyotype evolution of polyploids driven by segmental chromosome losses.
Tripsacum dactyloides (2n = 2x = 36) is an ancient tetraploid species. Here we report that T. dactyloides chromosomes contain an extraordinary tertiary constriction, which causes a radical and distant separation of a terminal segment from the chromosome. The relationships between extraordinary tertiary constriction and segmental chromosome loss as well as karyotype evolution of polyploid species are discussed.
Department of Horticulture, University of Wisconsin, Madison, Wisconsin 53706, USA.
Dal-Hoe
DH
Koo
Jiming
J
Jiang
D005075:Biological Evolution; D032461:Chromosomes, Plant / Q000235:genetics* / Q000648:ultrastructure; D018744:DNA, Plant / Q000235:genetics; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D008957:Models, Genetic; D006109:Poaceae / Q000145:classification / Q000235:genetics* / Q000648:ultrastructure; D011123:Polyploidy; D018626:Retroelements
D018744:DNA, Plant; D018626:Retroelements