Reconstruction of insect hormone pathways in an aquatic firefly, Sclerotia aquatilis (Coleoptera: Lampyridae), using RNA-seq

Abstract

Insect hormones: ecdysteroids and juvenile hormones have crucial functions during the regulation of different developmental pathways in insects. Insect metamorphosis is one of the primary pathways regulated by these hormones. The insect hormone biosynthetic pathway is conserved among arthropods, including insects, with some variations in the form of hormones used among each group of insects. In this study, the candidate genes involved in the insect hormone pathways and their functional roles were assessed in an aquatic firefly, Sclerotia aquatilis using a high-throughput RNA sequencing technique. Illumina next-generation sequencing (NGS) was used to generate transcriptome data for the different developmental stages (i.e., larva, pupa, and adult) of S. aquatilis. A total of 82,022 unigenes were generated across all different developmental stages. Functional annotation was performed for each gene, based on multiple biological databases, generating 46,230 unigenes. These unigenes were subsequently mapped using KEGG pathways. Accordingly, 221 protein-encoding genes involved in the insect hormone pathways were identified, including, JHAMT, CYP15A1, JHE, and Halloween family genes. Twenty potential gene candidates associated with the biosynthetic and degradation pathways for insect hormones were subjected to real-time PCR, reverse transcriptase PCR (RT-PCR) and sequencing analyses. The real-time PCR results showed similar expression patterns as those observed for transcriptome expression profiles for most of the examined genes. RT-PCR and Sanger sequencing confirmed the expressed coding sequences of these gene candidates. This study is the first to examine firefly insect hormone pathways, facilitating a better understanding of firefly growth and development.

Developmental Transcriptome Analysis of Red-Spotted Apollo Butterfly, Parnassius bremeri

“…The genes encoding farnesyl diphosphate synthase (FPPS), farnesol dehydrogenase (FDH), juvenile hormone acid methyltransferase (JHAMT), methyl farnesoate epoxidase (CYP15A1), Juvenile hormone epoxide hydrolase-like (JHEH), and Juvenile hormone esterase-like (JHE1) coding were manually curated and assigned to the Juvenile hormone metabolic pathway at each stage and tissue comparison [ 20 ]. In the overall comparisons, a total of 118 DEGs were downregulated, whereas 71 DEGs were upregulated with respect to the members of the JH signaling pathway.…”

Peppers in Diet: Genome-Wide Transcriptome and Metabolome Changes in Drosophila melanogaster

“…Glycine and serine metabolism provides the essential precursors for proteins and nucleic acid biosynthesis [ 60 ]. Integration of metabolomic and transcriptomic data revealed the dysregulation of the insect hormone biosynthesis pathway with the habanero-pepper versus control diet, which might affect insect metamorphosis in Drosophila [ 61 ]. These findings enhance the integration between transcripts and metabolomics and provide deeper insights into the molecular mechanisms involved in the response to dietary habanero-pepper consumption.…”

Peer Review #2 of "SMRT sequencing of the full-length transcriptome of the Rhynchophorus ferrugineus (Coleoptera: Curculionidae) (v0.1)"

“…As expected, massive transcriptome data of R. ferrugineus was generated, including 63,801 full-length transcripts with 2,964 bp of average length and 3,547 bp of N50 length. The amount of transcriptome data acquired in red palm weevil was much higher than that in Coleoptera insects with different developmental stages by second-generation sequencing, such as Hypothenemus hampei (average length 1,609.92 bp and N50 length 2,427 bp ) (Noriega et al, 2019), Nicrophorus orbicollis (average length 1,193 bp and N50 length 2,856 bp) (Won et al, 2018), Sclerotia aquatilis (average length 1,394 bp and N50 length 2,666 bp) (Chanchay et al, 2019), and Batocera horsfieldi (average length 1,188 bp and N50 length 3,143 bp) (Yang et al, 2018). Meanwhile, a total of 54,999 (86.20%) among 63,801 transcripts of R. ferrugineus were successfully annotated as known homologous genes using seven databases.…”

“…Short-reading transcriptome sequencing has been widely used to describe gene expression levels, and many model organisms and non-model organism transcriptomes were obtained by short-sequence sequencing on a second-generation sequencing platform (Nagalakshmi et al, 2008;Ekblom & Galindo, 2011;Djebali et al, 2012). Recently, the expression analysis of Coleoptera insects at different developmental stages have been studied using the next-generation sequencing method (Won et al, 2018;Chanchay et al, 2019;Noriega et al, 2019). Additionally, the research on transcriptome of R. ferrugineus intestinal microbes showed those microbes in the intestine of larva had profound effects on the immune stimulation and nutritional metabolism (Habineza et al, 2019;Muhammad et al, 2019).…”