Proteomic endorsed transcriptomic profiles of venom glands from Tityus obscurus and T. serrulatus scorpions

• Published in: PloS one Vol. 13; no. 3; p. e0193739
• Main Authors: de Oliveira, Ursula Castro, Nishiyama, Jr, Milton Yutaka, Dos Santos, Maria Beatriz Viana, Santos-da-Silva, Andria de Paula, Chalkidis, Hipócrates de Menezes, Souza-Imberg, Andreia, Candido, Denise Maria, Yamanouye, Norma, Dorce, Valquíria Abrão Coronado, Junqueira-de-Azevedo, Inácio de Loiola Meirelles
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 21-03-2018; Public Library of Science (PLoS)
• Subjects: Amino acids; Angiotensin; Antimicrobial peptides; Bioinformatics; Biology and Life Sciences; Bradykinin; Cardiac arrhythmia; Cathepsins; Chymotrypsin; Composition; Core making; Distribution; Endothelins; Enzymes; Epitopes; Evolution; Gene expression; Genetic aspects; Hypertension; Medicine and Health Sciences; Peptides; Peptidyl-dipeptidase A; Phylogenetics; Phylogeny; Physical Sciences; Physiological aspects; Potassium; Proteins; Proteomics; Research and Analysis Methods; Scorpions; Serine; Snakes; Sodium; Species; Tityus; Tityus obscurus; Tityus serrulatus; Toxins; Venom; Venom gland; Venoms; South America; Brazil
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0193739

Except for the northern region, where the Amazonian black scorpion, T. obscurus, represents the predominant and most medically relevant scorpion species, Tityus serrulatus, the Brazilian yellow scorpion, is widely distributed throughout Brazil, causing most envenoming and fatalities due to scorpion sting. In order to evaluate and compare the diversity of venom components of Tityus obscurus and T. serrulatus, we performed a transcriptomic investigation of the telsons (venom glands) corroborated by a shotgun proteomic analysis of the venom from the two species.
The putative venom components represented 11.4% and 16.7% of the total gene expression for T. obscurus and T. serrulatus, respectively. Transcriptome and proteome data revealed high abundance of metalloproteinases sequences followed by sodium and potassium channel toxins, making the toxin core of the venom. The phylogenetic analysis of metalloproteinases from T. obscurus and T. serrulatus suggested an intraspecific gene expansion, as we previously observed for T. bahiensis, indicating that this enzyme may be under evolutionary pressure for diversification. We also identified several putative venom components such as anionic peptides, antimicrobial peptides, bradykinin-potentiating peptide, cysteine rich protein, serine proteinases, cathepsins, angiotensin-converting enzyme, endothelin-converting enzyme and chymotrypsin like protein, proteinases inhibitors, phospholipases and hyaluronidases.
The present work shows that the venom composition of these two allopatric species of Tityus are considerably similar in terms of the major classes of proteins produced and secreted, although their individual toxin sequences are considerably divergent. These differences at amino acid level may reflect in different epitopes for the same protein classes in each species, explaining the basis for the poor recognition of T. obscurus venom by the antiserum raised against other species.