Daily genetic profiling indicates JAK/STAT signaling promotes early hepatic stellate cell transdifferentiation

AIM: To identify signaling pathways and genes that initiate and commit hepatic stellate cells (HSCs) to transdifferentiation

Differential toxicity and venom gland gene expression in Centruroides vittatus

Variation in venom toxicity and composition exists in many species. In this study, venom potency and venom gland gene expression was evaluated in Centruroides vittatus, size class I-II (immature) and size class IV (adults/penultimate instars) size classes. Venom toxicity was evaluated by probit analysis and returned ED50 values of 50.1 μg/g for class IV compared to 134.2 μg/g for class I-II 24 hours post injection, suggesting size class IV was 2.7 fold more potent. Next generation sequencing (NGS and qPCR were used to characterize venom gland gene expression. NGS data was assembled into 36,795 contigs, and annotated using BLASTx with UNIPROT. EdgeR analysis of the sequences showed statistically significant differential expression in transcripts associated with sodium and potassium channel modulation. Sodium channel modulator expression generally favored size class IV; in contrast, potassium channel modulators were favored in size class I-II expression. Real-time quantitative PCR of 14 venom toxin transcripts detected relative expression ratios that paralleled NGS data and identified potential family members or splice variants for several sodium channel modulators. Our data suggests ontogenetic differences in venom potency and venom related genes expression exist between size classes I-II and IV

Transcripts associated with venom and venom toxicity.

<p>Transcripts associated with venom and venom toxicity.</p

Distribution of taxonomic identification within scorpion species.

<p>Taxonomic identification of 2,642 annotated transcripts with species identification hits >10e^-5. Taxa higher than the order Scorpiones represented in “other” category.</p

<i>Centruroides vittatus</i> size classes.

<p>Size class determined by measuring scorpion length from prosoma to the posterior of the mesosoma.</p

Differential toxicity and venom gland gene expression in <i>Centruroides vittatus</i>

<div><p>Variation in venom toxicity and composition exists in many species. In this study, venom potency and venom gland gene expression was evaluated in <i>Centruroides vittatus</i>, size class I-II (immature) and size class IV (adults/penultimate instars) size classes. Venom toxicity was evaluated by probit analysis and returned ED₅₀ values of 50.1 μg/g for class IV compared to 134.2 μg/g for class I-II 24 hours post injection, suggesting size class IV was 2.7 fold more potent. Next generation sequencing (NGS and qPCR were used to characterize venom gland gene expression. NGS data was assembled into 36,795 contigs, and annotated using BLASTx with UNIPROT. EdgeR analysis of the sequences showed statistically significant differential expression in transcripts associated with sodium and potassium channel modulation. Sodium channel modulator expression generally favored size class IV; in contrast, potassium channel modulators were favored in size class I-II expression. Real-time quantitative PCR of 14 venom toxin transcripts detected relative expression ratios that paralleled NGS data and identified potential family members or splice variants for several sodium channel modulators. Our data suggests ontogenetic differences in venom potency and venom related genes expression exist between size classes I-II and IV.</p></div

Top 29 expressed sequences identified from the UniProt database.

<p>Top 29 expressed sequences identified from the UniProt database.</p

Effective dose response curves.

<p>Live crickets were injected with, PBS (0), 20, 65, or 134.2 μg/g crude venom. (A) ED50 curves for class IV after 24 hours were 50.1 μg/g (p<0.01) (B) ED50 curves for class I–II after 24 hours were 134.2 μg/g (p <0.02). (C) Temporal responses to 130 μg/g venom were monitored every hour for 4 hours then again at the 24 hour time point. Class I—II venom induced the inability to right (UTR) in 37.5–50.0% of the individuals during early time periods (1–4 hours). Twenty-four hours post stimulation one death (12.5%) was recorded with the remaining individuals unaffected or UTR. Class IV venom demonstrated greater potency inducing UTR response in 62.5% after 1 hour, and a significant shift from UTR to death overtime (Black (UTR) to White (Dead)) (n = 8 per group).</p