The wide distribution and horizontal transfers of beta satellite DNA in eukaryotes

Jiawen Yang,Bin Yuan,Yu Wu,Meiyu Li,Jian Li,Donglin Xu,Zeng-Hong Gao,Guangwei Ma,Yiting Zhou,Yachao Zuo,Jin Wang,Yabin Guo

doi:10.1016/j.ygeno.2020.10.006

Abstract

Beta satellite DNA (satDNA), also known as Sau3A sequences, are repetitive DNA sequences reported in human and primate genomes. It is previously thought that beta satDNAs originated in old world monkeys and bursted in great apes. In this study, we searched 7821 genome assemblies of 3767 eukaryotic species and found that beta satDNAs are widely distributed across eukaryotes. The four major branches of eukaryotes, animals, fungi, plants and Harosa/SAR, all have multiple clades containing beta satDNAs. These results were also confirmed by searching whole genome sequencing data (SRA) and PCR assay. Beta satDNA sequences were found in all the primate clades, as well as in Dermoptera and Scandentia, indicating that the beta satDNAs in primates might originate in the common ancestor of Primatomorpha or Euarchonta. In contrast, the widely patchy distribution of beta satDNAs across eukaryotes presents a typical scenario of multiple horizontal transfers.

Highlights

The genomes of eukaryotes comprise large tracts of repeated sequences, including satellite DNAs, minisatellite, microsatellite sequences and transposable elements (Charlesworth, Sniegowski, Stephan 1994)
Beta satellite DNA (satDNA) typically exist as tandem repeats in human genome, and the similar pattern were identified in the contigs/scaffolds of certain non-primate species (Fig. S2), indicating that they may play similar roles as they do in primate genomes
Similar to the genome BLAST results, beta satDNAs were found in all primate clades, as well as in Dermoptera and Scandentia

Summary

Introduction

The genomes of eukaryotes comprise large tracts of repeated sequences, including satellite DNAs (satDNAs), minisatellite, microsatellite sequences and transposable elements (Charlesworth, Sniegowski, Stephan 1994). After filtering the BLAST outputs, we found 33,150 beta satDNA copies in 166 genome assemblies of 116 species (Fig. 1, Fig. S1, Table S1 and S2, and Supplementary File 1). Beta satDNAs were found in the genome assemblies of four Bovinae species.

Results

Conclusion