Molecular evolution and epigenetics of Thysanoptera derived from the Frankliniella fusca genome assembly

Monday, November 14, 2022

11:42 AM – 11:54 AM PT

Location: Vancouver Convention Centre, Meeting Room 221/222

Presenting Author(s)

Michael A. Catto

Graduate Student
University of Georgia
Athens, Georgia

Co-Author(s)

PL

Paul Labadie

North Carolina State University
Raleigh, North Carolina
AJ

Alana Lynn Jacobson

Auburn University
Auburn, Alabama
GK

George Kennedy

North Carolina State University
Raleigh, North Carolina
Rajagopalbabu Srinivasan

Professor
University of Georgia
Griffin, Georgia
BH

Brendan G. Hunt

Associate Professor
University of Georgia
Griffin, Georgia

The tobacco thrips (Frankliniella fusca) is an agriculturally important pest that can transmit the tomato spotted wilt orthotospovirus to crops such as tobacco, peanut, and tomato. The structural and functional genomics within the order Thysanoptera has only begun to be explored, with genome assemblies of the melon thrips (Thrips palmi) and western flower thrips (Frankliniella occidentalis) previously reported. We report the genome assembly of F. fusca, the first Frankliniella genome assembled from long-read sequence data. Analyses of protein evolution based on F. fusca and F. occidentalis orthologs revealed that around 1% of genes have a signal of positive selection when averaged across constituent codons. Consideration of the ~1,000 genes with a transcriptional response to F. fusca infection by tomato spotted wilt virus revealed no consistent differences in the rate of protein evolution for such genes when compared to others. However, 10 virus-responsive genes exhibit substitution patterns consistent with positive selection, highlighting potential interaction between protein evolution and pressures related to virus infection. Investigation of the mutational consequences of DNA methylation revealed the Frankliniella genomes have similar methylation patterns that are in line with expectations from other insect taxa, but that genes with homology to DNA methyltransferase 3 in each species are numerous and incomplete, a relatively unique phenomenon.