Chromosomal Mapping of Tandem Repeats Revealed Massive Chromosomal Rearrangements and Insights Into Senna tora Dysploidy

• DOI: 10.3389/fpls.2021.629898
• Publication Date: 2021-02-10T15:27:47Z
• Authors: Nomar Espinosa Wa...; Remnyl Joyce Pell...; Sang-Ho Kang; Hyun Hee Kim
• Keywords: Direct repeat; Subtelomere

Tandem repeats can occupy a large portion of plant genomes and either cause or result from chromosomal rearrangements, which are important drivers dysploidy-mediated karyotype evolution speciation. To understand the contribution tandem in shaping extant Senna tora dysploid karyotype, we analyzed composition abundance S. genome compared distribution these between closely related euploid, occidentalis . Using read clustering algorithm, identified major visualized their by fluorescence situ hybridization. We eight independent covering ~85 Mb ~12% genome. The unit lengths copy numbers had ranges 7–5,833 bp 325–2.89 × 10 6 , respectively. Three short duplicated sequences were found 45S rDNA intergenic spacer, one was also detected at an extra-NOR locus. canonical telomeric repeat (TTTAGGG) n as very intense signals numerous pericentromeric interstitial loci. StoTR05_180, showed subtelomeric predominantly unusual not only enabled easy identification individual chromosomes but revealed massive rearrangements that have likely played roles its karyotype.