Differential venom gland gene expression analysis of juvenile and adult scorpions Androctonus crassicauda

Background

The Androctonus crassicauda, belonging to the genus Androctonus of the family Buthidae, is the most venomous scorpion in Middle East countries. However, the venom gland transcriptome profile of A. crassicauda scorpion has not yet been studied. In this study, we elucidated and compared the venom gland gene expression profiles of adult and juvenile male scorpion A. crassicauda using high-throughput transcriptome sequencing. This is the first report of transcriptional analysis of the venom glands of scorpions in different growth stages, with insights into the identification of the key genes during venom gland development.

Results

A total of 209,951 mRNA transcripts were identified from total RNA-seq data, of which 963 transcripts were differentially expressed (DE) in adult and juvenile scorpions (p < 0.01). Overall, we identified 558 up-regulated and 405 down-regulated transcripts in the adult compared to the juvenile scorpions, of which 397 and 269 unique unigenes were annotated, respectively. GO and KEGG enrichment analyses indicated that the metabolic, thermogenesis, cytoskeleton, estrogen signaling, GnRH signaling, growth hormone signaling, and melanogenesis pathways were affected by two different growth conditions and the results suggested that the DE genes related to those pathways are important genes associated with scorpion venom gland development, in which they may be important in future studies, including Chs, Elovl, MYH, RDX, ACTN, VCL, PIP5K, PP1C, FGFR, GNAS, EGFR, CREB, CoA, PLCB, CALM, CACNA, PKA and CAMK genes.

Conclusions

These findings broadened our knowledge of the differences between adult and juvenile scorpion venom and opened new perspectives on the application of comparative transcriptome analysis to identify the special key genes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08866-1.

Arizona Ridge-nosed rattlesnake envenomation: Case report of a personal encounter with the official state reptile of Arizona, Crotalus willardi willardi

This case report describes the effects of an envenomation from one of the most infrequently encountered species of rattlesnake in the United States, Crotalus willardi willardi (C. w. willardi), the Arizona Ridge-nosed Rattlesnake. A previously healthy 57-year-old male sustained a bite to his non-dominant hand from a C. w. willardi. The most pronounced effect from the envenomation was edema and progression of edema that extended from his hand to the mid bicep. He also experienced erythema and tenderness to palpation in the affected limb, and some diminished range of motion in the hand. He expressed only minimal pain. Other than a mildly positive D-Dimer and leukocytosis, he had no significant hematologic effects and no systemic effects. He was treated with standard doses of Crotalidae Polyvalent Immune Fab (Ovine). He reported complete recovery from the envenomation within three days of the bite. Although envenomation from rattlesnakes is somewhat common in Arizona, knowing the exact species of snake is not. Confirmed documentation is exceedingly rare as most people do not recognize the different rattlesnake species. In addition, some species of rattlesnake (such as C. w. willardi) are especially reclusive and found only in isolated mountainous regions. Being able to confirm an envenomation by C. w. willardi would require not only someone knowledgeable in herpetology, but also, preferably, photographic evidence. This case has both.

Necrotizing fasciitis following venomous snakebites in a tertiary hospital of southwest Taiwan

BACKGROUND

Necrotizing fasciitis following venomous snakebites is uncommon. The purpose of this study was to describe the initial clinical features of necrotizing fasciitis after snakebites, and to identify the risk factors for patients with cellulitis who later developed necrotizing fasciitis.

METHODS

Sixteen patients with surgically confirmed necrotizing fasciitis and 25 patients diagnosed with cellulitis following snakebites were retrospectively reviewed over a 6-year period. Differences in patient characteristics, clinical presentations, snake species and laboratory data were compared between the necrotizing fasciitis and the cellulitis groups.

RESULTS

None of the 41 patients died after being bitten by a snake. Twenty-nine patients (70.7%) were bitten by a cobra. Enterococcus species and Morganella morganii were the most common pathogens identified in wound cultures. Relative to the cellulitis group, the necrotizing fasciitis group had significantly higher rates of hemorrhagic bullae (p=0.000), patients with underlying chronic disease (p=0.019), white blood cell counts (p=0.035), segmented white cell counts (p=0.02), and days of hospitalization (p=0.001).

CONCLUSIONS

Victims of venomous snakebites should be admitted for close monitoring of secondary wound infections. The risk factors of developing necrotizing fasciitis from cellulitis following snakebites were associated with chronic underlying diseases and leukocytosis (total white blood-cell counts ≥10000cells/mm³ and ≥80% of segmented leukocyte forms). Physicians should be alert to a worsening wound condition after a snakebite, and surgical interventions should be performed for established necrotizing fasciitis with the empirical use of third-generation cephalosporins plus other regimens.