Abstract Detail

Comparative Genomics/Transcriptomics

Roberts, Wade [1], Alverson, Andrew [1].

Evidence for a recent whole-genome duplication in a diatom genome.

Diatoms (Bacillariophyta) are one of the most species-rich lineages of microbial eukaryotes and contribute significantly to global primary production. Whole-genome duplication (WGD) followed by gene loss and specialization has long been thought to be a powerful mechanism of evolutionary innovation. However, the role of WGD in diatom genome evolution and diversification remains unknown. Long-read sequencing now provides a powerful and cost-effective tool to generate high-quality genomes from understudied groups, such as diatoms. Here, we sequenced the genome of a diatom species and provide initial evidence that it underwent a recent WGD event followed by diploidization. We used nanopore sequencing to assemble a high-quality and contaminant-free genome that is 75 Mb and contains 27,336 genes. We found that nearly all genes were duplicated, but expression patterns and the relative frequencies of heterozygous variants and kmers indicated a diploid genome. We additionally used analyses of synteny, synonymous divergence, and gene trees to provide additional evidence supporting a recent WGD. These results provide important insights into diatom genome evolution and function.

1 - University Of Arkansas, Department Of Biological Sciences, Science And Engineering 601, Fayetteville, AR, 72701, United States

Keywords:
Diatoms
minION genome sequencing
Whole-genome duplication
diploidization.

Presentation Type: Oral Paper
Session: CG2, Functional & Comparative Genetics/Genomics II
Location: Virtual/Virtual
Date: Wednesday, July 29th, 2020
Time: 3:00 PM
Number: CG2001
Abstract ID:648
Candidate for Awards:None