Species diversity of Androctonus crassicauda and Hemiscorpius lepturus using different metabolic genes expressed in RNA-seq data

Abstract

Introduction: The order of scorpions belongs to the category of arachnids and the branch of
arthropods, and according to the extensive studies that are being carried out today in the field
of phylogenetic and morphological around the world, the classification of scorpions is also
being updated. The aim of this studies reconstructs the metabolic network of Androctonus
crassicauda and Hemiscorpius lepturus using RNA-seq studies for suggestion of key
metabolic genes differentially expressed between two scorpion species as a molecular marker
to evaluate the genetic diversity of different scorpion species.
Materials & methods: For this purpose, Scorpions were caught using ultraviolet light in
different areas of Khuzestan province (10 samples of each species). Scorpions were poisoned
by electric shock method, and after 72 hours of poisoning, the venom gland was isolated and
powdered using a porcelain mortar and liquid nitrogen. RNA extraction from the venom gland
was performed using the commercial RNeasy Animal Mini Kit (Qiagen, Valencia, CA, USA)
according to the company's instructions. Transcriptome sequencing and differential gene
expression analysis of two scorpion species were performed by RSEM software.
Results: The results of analyzes showed that a total of 688060 genes were identified in two
species, of which 42676 genes had significant differences in expression (p<0.05). The gene
ontology of the differentially expressed genes was performed using Kegg and GO databases
and the results showed that the genes involved in the metabolic pathway are the most abundant.
Reconstruction of scorpion metabolic network and its analysis using string database and
cystoscope software led to the identification of 5 metabolic hub genes. Finally, using the amino
acid sequences of Hub genes (triose phosphate isomerase, citrate synthase, glucose
6-phosphate isomerase, catalase and enolase), a phylogenetic tree was constructed using 7
scorpion species.
Conclusion: This study evaluated the use of these 5 metabolic genes to study phylogenetic
relationships in scorpions.