Supplementary Notes on Somatostatin Venom Analogs by Cone Snails
Study Focus
Investigates venom analogs of somatostatin (SS) evolved by fish-hunting cone snails.
Aims to link predatory behavior with the identification of potential drug leads.
Key Contributors
Iris Bea L. Ramiro, Walden E. Bjørn-Yoshimoto, Julita S. Imperial, et al.
Published in Science Advances, March 2022, DOI: 10.1126/sciadv.abk1410
Figures & Explanations
Fig. S1: Mass determination confirms molecular mass of Consomatin Ro1 variant.
Techniques used: Edman degradation, transcriptome analysis.
Fig. S2: Reverse-phase elution profiles display behavior of Consomatin Ro1 against other variants.
Fig. S3: Precursor sequences of Consomatin Ro1 align with other consomatins showing signal peptides and predicted mature toxins.
Red regions: Predicted mature toxin encoding.
Data obtained using SignalP and PeptideCutter software.
Fig. S4: Stability profiles for human SS-14 and Consomatin Ro1 over 24 hours observed via LC/MS peak area analysis.
Fig. S5: Structures of Consomatin Ro1 in crystal formation showcasing interactions and stacking arrangements critical for molecular stability and alignment.
Unique orientation due to PEG interactions.
Fig. S6: Multiple views of Consomatin Ro1 in a crystal structure highlighting differences in residue orientations.
Fig. S7: Calcium signal responses in zebrafish CNS neurons showing varying responses to Consomatin Ro1 and somatostatin, suggesting bioactivity.
14.14% of neurons responded to Consomatin Ro1.
Tables Summarized
Table S1: Timeline of predation events for Conus neocostatus detailing behaviors captured in various video segments.
Table S2: Analysis of C. rolani venom fractions showing bioactivity in mice with detailed behavioral outcomes post-injection.
Table S3: Crystallographic data for Consomatin Ro1 and its refinement statistics including resolution and reflections measured, giving insights into molecular structure analysis.
Table S4: EC50 values for human somatostatins and related consomatins at SST1-5 receptors, indicating compound potency.
Table S5: Overview of venom gland transcriptome datasets used for SS-like sequence identification across various Conus species.
Movie Insights
Movies S1-S6: Document various hunting strategies of cone snails, including taser-and-tether, net-hunting, and ambush techniques, emphasizing their predation mechanics.
Results
Bioactivity of Consomatin Ro1:
14.14% of zebrafish CNS neurons showed a response to Consomatin Ro1, indicating significant bioactivity.
The calcium signal responses in the neurons suggest that Consomatin Ro1 is capable of modulating neuronal activity similarly to somatostatin.
Stability Profiles:
LC/MS peak area analysis revealed that Consomatin Ro1 maintained stability over a 24-hour period, which is critical for potential therapeutic applications.
Structural Insights:
Crystallographic data of Consomatin Ro1 showed unique stacking arrangements and interactions due to PEG, which may influence its stability and function.
Multiple structural views highlight differences in residue orientations, suggesting specific conformations are important for activity.
Key Data
Fig. S1: Mass determination confirms the molecular mass of Consomatin Ro1.
Fig. S4: Stability profiles comparing human SS-14 and Consomatin Ro1, indicating favorable stability for Consomatin Ro1.
Table S4: EC50 values at SST1-5 receptors show the potency of Consomatin Ro1 compared to human somatostatins, providing quantitative insights on its effectiveness.
Table S5: Overview of venom gland transcriptome datasets, emphasizing the extensive diversity and potential for SS-like sequence identification across various Conus species.
Background
Cone snails are known for their complex venom, which includes various bioactive peptides.
Venom analogs of somatostatin evolved by fish-hunting cone snails are of specific interest for their potential medicinal properties.
Past Observations
Previous studies indicated that cone snail venoms can influence neuronal signaling and have applications in pain management and other therapeutic areas.
Early insights show that somatostatin-related peptides might hold similar bioactivity.
Problem
The challenge lies in identifying new compounds that can effectively mimic or enhance the neuropharmacological effects of somatostatin.
Additionally, understanding the structural basis for the activity of these peptides remains limited.
Question
Can the identified venom analog Consomatin Ro1 exhibit bioactivity similar to that of somatostatin, and what structural features contribute to its function?
Hypothesis
Consomatin Ro1 will display bioactive properties comparable to somatostatin due to its structural similarity and unique evolutionary adaptations in the cone snail venom.
Approach
To test the hypothesis, the study will evaluate the biological activity of Consomatin Ro1 in various experimental models, particularly focusing on neuroactivity and stability profiles.
This includes comparing responses in neuronal signaling assays to those evoked by somatostatin.
Methods
The study will employ Edman degradation and transcriptome analysis to determine the molecular characteristics of Consomatin Ro1.
Techniques like LC/MS for stability analysis and calcium signaling assays in zebrafish CNS neurons will be used to assess bioactivity.
Crystallographic analysis will provide insights into its structural properties.
Results
Bioactivity of Consomatin Ro1:
14.14% of zebrafish CNS neurons showed a response to Consomatin Ro1, indicating significant bioactivity.
The calcium signal responses in the neurons suggest that Consomatin Ro1 is capable of modulating neuronal activity similarly to somatostatin.
Stability Profiles:
LC/MS peak area analysis revealed that Consomatin Ro1 maintained stability over a 24-hour period, which is critical for potential therapeutic applications.
Structural Insights:
Crystallographic data of Consomatin Ro1 showed unique stacking arrangements and interactions due to PEG, which may influence its stability and function.
Multiple structural views highlight differences in residue orientations, suggesting specific conformations are important for activity.