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Creating and Applying a Reference to Facilitate the Discussion and Classification of Proteins in a Diverse Group
Published on: August 16, 2017
Molecular evolution of PIII-SVMP and RGD disintegrin genes from the genus Crotalus
Julio G Soto1, Stephanie A White, Steven R Reyes
1Biological Sciences Department, San Jose State University, One Washington Square, Duncan Hall 254, San Jose, CA 95192-0100, United States. jsoto3@emai.sjsu.edu
Gene
|November 23, 2006
Summary
Researchers identified RGD disintegrins and PIII-SVMPs from rattlesnake venom. Phylogenetic analysis revealed distinct evolutionary paths for these snake venom proteins, suggesting rapid evolution of PIII-SVMPs leading to RGD disintegrins.
Area of Science:
- Molecular Biology
- Evolutionary Biology
- Biochemistry
Background:
- Disintegrins, including RGD disintegrins and PIII-SVMPs, are found in Crotalus spp. rattlesnake venom.
- These proteins play roles in biological processes, and understanding their evolution is crucial.
Purpose of the Study:
- To isolate and characterize RGD disintegrin and PIII-SVMP cDNAs from specific rattlesnake species.
- To perform phylogenetic analysis to understand the evolutionary relationships between these venom proteins.
Main Methods:
- Isolation of six cDNAs (three RGD disintegrins, three PIII-SVMPs) from rattlesnake venom glands using RT-PCR.
- Amino acid identity comparisons between the isolated proteins.
- Phylogenetic analysis using Neighbor-joining, Phi(ST) pairwise comparison, and AMOVA on DNA sequences.
Main Results:
- Identified six cDNAs: atroxatin, mojastin, viridistatin (RGD disintegrins) and catroriarin, scutiarin, viristiarin (PIII-SVMPs).
- High amino acid identity observed within RGD disintegrins and PIII-SVMPs.
- Phylogenetic analysis showed distinct clades for RGD/MVD disintegrins and PIII-SVMPs, with significant genetic differences.
Conclusions:
- The study suggests rapid evolution of PIII-SVMP genes led to the emergence of RGD disintegrin genes in Crotalus.
- Post-divergence, PIII-SVMP genes accumulated mutations at a lower rate compared to the evolutionary events leading to RGD disintegrins.
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