InsectOR – webserver for sensitive identification of insect olfactory receptor genes from non-model genomes

Abstract

13Insect Olfactory Receptors (ORs) are diverse family of membrane protein receptors responsi- 14 ble for most of the insect olfactory perception and communication, and hence they are of utmost im-15 portance for developing repellents or pesticides. Hence, accurate gene prediction of insect ORs from 16 newly sequenced genomes is an important but challenging task. We have developed a dedicated web-17 server, 'insectOR', to predict and validate insect OR genes using multiple gene prediction algo-18 rithms, accompanied by relevant validations. It is possible to employ this sever nearly automatically 19 and perform rapid prediction of the OR gene loci from thousands of OR-protein-to-genome align-20 ments, resolve gene boundaries for tandem OR genes and refine them further to provide more com-21 plete OR gene models. InsectOR outperformed the popular genome annotation pipelines (MAKER 22 and NCBI eukaryotic genome annotation) in terms of overall sensitivity at base, exon and locus lev-23 el, when tested on two distantly related insect genomes. It displayed more than 95% nucleotide level 24 precision in both tests. Finally, given the same input data and parameters, InsectOR missed less than 25 2% gene loci, in contrast to 55% loci missed by MAKER for Drosophila melanogaster. The web-26

Expansion and accelerated evolution of 9-exon odorant receptors in Polistes paper wasps

“…Some long Trinity genes contain multiple 7-transmembrane domains 138 and likely represent concatenated OR genes. The small fraction of the P. fuscatus OR repertoire 139 predicted by transcriptome assembly is consistent with previous observations that annotation of 140 OR repertoires using only transcriptome data typically fails to recover all ORs (Karpe et al 2016(Karpe et al , 141 2017(Karpe et al , 2020. 142 Manual gene annotation of P. fuscatus ORs recovered 231 gene models across 28 scaffolds ( Figure S2), of which 28 are pseudogenes and 10 are incomplete gene models (7 missing N termini, 2 missing C termini, and one missing both N and C termini).…”