Dataset Information

Deep sequencing analysis of toad Rhinella schneideri skin glands and partial biochemical characterization of its cutaneous secretion.

ABSTRACT:

Background

Animal poisons and venoms are sources of biomolecules naturally selected. Rhinella schneideri toads are widespread in the whole Brazilian territory and they have poison glands and mucous gland. Recently, protein from toads' secretion has gaining attention. Frog skin is widely known to present great number of host defense peptides and we hypothesize toads present them as well. In this study, we used a RNA-seq analysis from R. schneideri skin and biochemical tests with the gland secretion to unravel its protein molecules.

Methods

Total RNA from the toad skin was extracted using TRizol reagent, sequenced in duplicate using Illumina Hiseq2500 in paired end analysis. The raw reads were trimmed and de novo assembled using Trinity. The resulting sequences were submitted to functional annotation against non-redundant NCBI database and Database of Anuran Defense Peptide. Furthermore, we performed caseinolytic activity test to assess the presence of serine and metalloproteases in skin secretion and it was fractionated by fast liquid protein chromatography using a reverse-phase column. The fractions were partially sequenced by Edman's degradation.

Results

We were able to identify several classes of antimicrobial peptides, such as buforins, peroniins and brevinins, as well as PLA₂, lectins and galectins, combining protein sequencing and RNA-seq analysis for the first time. In addition, we could isolate a PLA₂ from the skin secretion and infer the presence of serine proteases in cutaneous secretion.

Conclusions

We identified novel toxins and proteins from R. schneideri mucous glands. Besides, this is a pioneer study that presented the in depth characterization of protein molecules richness from this toad secretion. The results obtained herein showed evidence of novel AMP and enzymes that need to be further explored.

SUBMITTER: Shibao PYT

PROVIDER: S-EPMC6267030 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

Deep sequencing analysis of toad <i>Rhinella schneideri</i> skin glands and partial biochemical characterization of its cutaneous secretion.

Shibao Priscila Yumi Tanaka PYT Cologna Camila Takeno CT Morandi-Filho Romualdo R Wiezel Gisele Adriano GA Fujimura Patricia Tiemi PT Ueira-Vieira Carlos C Arantes Eliane Candiani EC

The journal of venomous animals and toxins including tropical diseases 20181129

<h4>Background</h4>Animal poisons and venoms are sources of biomolecules naturally selected. <i>Rhinella schneideri</i> toads are widespread in the whole Brazilian territory and they have poison glands and mucous gland. Recently, protein from toads' secretion has gaining attention. Frog skin is widely known to present great number of host defense peptides and we hypothesize toads present them as well. In this study, we used a RNA-seq analysis from <i>R. schneideri</i> skin and biochemical tests ...[more]

PMID: 30519258

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