In silico mining and FISH mapping of a chromosome-specific satellite DNA in Capsicum annuum L

Abstract

Background: A large proportion of eukaryote nuclear genomes is composed of repetitive DNA. Tracing the dynamics of repetitive elements in the genomes of related taxa can reveal important information about their phylogenic relationships as well as traits that have become distinct to a lineage.

Objective: Study the genomic abundance and chromosomal location of repetitive DNA in Capsicum annuum L. to understand the repeat dynamics.

Method: We quantified repeated DNA content in the C. annuum genome using the RepeatExplorer pipeline.

Results: About 42% of the C. annuum genome dataset comprised repetitive elements. Of these, 0.011, 0.98, 3.09, and 0.024% represented high and low confidence satellite repeats, putative long-terminal repeats (LTRs), and rDNA sequences, respectively. One novel high confidence 167-bp satellite repeat with a genomic proportion of 0.011%, Ca167TR, was identified. Furthermore, FISH with Ca167TR on metaphase chromosomes of C. annuum revealed signals in the subtelomeric regions of the short and long arms of chromosome 3 and 4, respectively.

Conclusion: Further understanding of the origin and associated functions of Ca167TR and other repeats in Capsicum will give us insights into the genomic relationships and functions of the genome.

Keywords: Capsicum annuum L.; FISH; Karyotype; RepearExplorer; Repetitive DNA.