the cotton centromere contains a ty3-gypsy-like ltr retroelement棉花着丝粒包含ty3-gypsy-like ltr retroelement.pdfVIP

The Cotton Centromere Contains a Ty3-gypsy-like LTR Retroelement 1 1 1 1 1 4 Song Luo , Jennifer Mach , Bradley Abramson , Rolando Ramirez , Robert Schurr , Pierluigi Barone , 2,3 4 Gregory Copenhaver , Otto Folkerts * 1 Chromatin, Inc., Chicago, Illinois, United States of America, 2 Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America, 3 Carolina Center for Genome Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America, 4 Chromatin, Inc., Champaign, Illinois, United States of America Abstract The centromere is a repeat-rich structure essential for chromosome segregation; with the long-term aim of understanding centromere structure and function, we set out to identify cotton centromere sequences. To isolate centromere-associated sequences from cotton, (Gossypium hirsutum) we surveyed tandem and dispersed repetitive DNA in the genus. Centromere- associated elements in other plants include tandem repeats and, in some cases, centromere-specific retroelements. Examination of cotton genomic survey sequences for tandem repeats yielded sequences that did not localize to the centromere. However, among the repetitive sequences we also identified a gypsy-like LTR retrotransposon (Centromere Retroelement Gossypium, CRG) that localizes to the centromere region of all chromosomes in domestic upland cotton, Gossypium hirsutum, the major commercially grown cotton. The location of the functional centromere was confirmed by immunostaining with antiserum to the centromere