Mapping the Conformation Space of Wildtype and Mutant H-Ras with a Memetic, Cellular, and Multiscale Evolutionary Algorithm.

An important goal in molecular biology is to understand functional changes upon single-point mutations in proteins. Doing so through a detailed characterization of structure spaces and underlying energy landscapes is desirable but continues to challenge methods based on Molecular Dynamics. In this p...

Full description

Saved in:
Bibliographic Details
Main Authors: Rudy Clausen, Buyong Ma, Ruth Nussinov, Amarda Shehu
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2015-09-01
Series:PLoS Computational Biology
Online Access:https://doi.org/10.1371/journal.pcbi.1004470
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849331166903009280
author Rudy Clausen
Buyong Ma
Ruth Nussinov
Amarda Shehu
author_facet Rudy Clausen
Buyong Ma
Ruth Nussinov
Amarda Shehu
author_sort Rudy Clausen
collection DOAJ
description An important goal in molecular biology is to understand functional changes upon single-point mutations in proteins. Doing so through a detailed characterization of structure spaces and underlying energy landscapes is desirable but continues to challenge methods based on Molecular Dynamics. In this paper we propose a novel algorithm, SIfTER, which is based instead on stochastic optimization to circumvent the computational challenge of exploring the breadth of a protein's structure space. SIfTER is a data-driven evolutionary algorithm, leveraging experimentally-available structures of wildtype and variant sequences of a protein to define a reduced search space from where to efficiently draw samples corresponding to novel structures not directly observed in the wet laboratory. The main advantage of SIfTER is its ability to rapidly generate conformational ensembles, thus allowing mapping and juxtaposing landscapes of variant sequences and relating observed differences to functional changes. We apply SIfTER to variant sequences of the H-Ras catalytic domain, due to the prominent role of the Ras protein in signaling pathways that control cell proliferation, its well-studied conformational switching, and abundance of documented mutations in several human tumors. Many Ras mutations are oncogenic, but detailed energy landscapes have not been reported until now. Analysis of SIfTER-computed energy landscapes for the wildtype and two oncogenic variants, G12V and Q61L, suggests that these mutations cause constitutive activation through two different mechanisms. G12V directly affects binding specificity while leaving the energy landscape largely unchanged, whereas Q61L has pronounced, starker effects on the landscape. An implementation of SIfTER is made available at http://www.cs.gmu.edu/~ashehu/?q=OurTools. We believe SIfTER is useful to the community to answer the question of how sequence mutations affect the function of a protein, when there is an abundance of experimental structures that can be exploited to reconstruct an energy landscape that would be computationally impractical to do via Molecular Dynamics.
format Article
id doaj-art-9c4fd0d3cd874813925de4c604fb7e78
institution Kabale University
issn 1553-734X
1553-7358
language English
publishDate 2015-09-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Computational Biology
spelling doaj-art-9c4fd0d3cd874813925de4c604fb7e782025-08-20T03:46:42ZengPublic Library of Science (PLoS)PLoS Computational Biology1553-734X1553-73582015-09-01119e100447010.1371/journal.pcbi.1004470Mapping the Conformation Space of Wildtype and Mutant H-Ras with a Memetic, Cellular, and Multiscale Evolutionary Algorithm.Rudy ClausenBuyong MaRuth NussinovAmarda ShehuAn important goal in molecular biology is to understand functional changes upon single-point mutations in proteins. Doing so through a detailed characterization of structure spaces and underlying energy landscapes is desirable but continues to challenge methods based on Molecular Dynamics. In this paper we propose a novel algorithm, SIfTER, which is based instead on stochastic optimization to circumvent the computational challenge of exploring the breadth of a protein's structure space. SIfTER is a data-driven evolutionary algorithm, leveraging experimentally-available structures of wildtype and variant sequences of a protein to define a reduced search space from where to efficiently draw samples corresponding to novel structures not directly observed in the wet laboratory. The main advantage of SIfTER is its ability to rapidly generate conformational ensembles, thus allowing mapping and juxtaposing landscapes of variant sequences and relating observed differences to functional changes. We apply SIfTER to variant sequences of the H-Ras catalytic domain, due to the prominent role of the Ras protein in signaling pathways that control cell proliferation, its well-studied conformational switching, and abundance of documented mutations in several human tumors. Many Ras mutations are oncogenic, but detailed energy landscapes have not been reported until now. Analysis of SIfTER-computed energy landscapes for the wildtype and two oncogenic variants, G12V and Q61L, suggests that these mutations cause constitutive activation through two different mechanisms. G12V directly affects binding specificity while leaving the energy landscape largely unchanged, whereas Q61L has pronounced, starker effects on the landscape. An implementation of SIfTER is made available at http://www.cs.gmu.edu/~ashehu/?q=OurTools. We believe SIfTER is useful to the community to answer the question of how sequence mutations affect the function of a protein, when there is an abundance of experimental structures that can be exploited to reconstruct an energy landscape that would be computationally impractical to do via Molecular Dynamics.https://doi.org/10.1371/journal.pcbi.1004470
spellingShingle Rudy Clausen
Buyong Ma
Ruth Nussinov
Amarda Shehu
Mapping the Conformation Space of Wildtype and Mutant H-Ras with a Memetic, Cellular, and Multiscale Evolutionary Algorithm.
PLoS Computational Biology
title Mapping the Conformation Space of Wildtype and Mutant H-Ras with a Memetic, Cellular, and Multiscale Evolutionary Algorithm.
title_full Mapping the Conformation Space of Wildtype and Mutant H-Ras with a Memetic, Cellular, and Multiscale Evolutionary Algorithm.
title_fullStr Mapping the Conformation Space of Wildtype and Mutant H-Ras with a Memetic, Cellular, and Multiscale Evolutionary Algorithm.
title_full_unstemmed Mapping the Conformation Space of Wildtype and Mutant H-Ras with a Memetic, Cellular, and Multiscale Evolutionary Algorithm.
title_short Mapping the Conformation Space of Wildtype and Mutant H-Ras with a Memetic, Cellular, and Multiscale Evolutionary Algorithm.
title_sort mapping the conformation space of wildtype and mutant h ras with a memetic cellular and multiscale evolutionary algorithm
url https://doi.org/10.1371/journal.pcbi.1004470
work_keys_str_mv AT rudyclausen mappingtheconformationspaceofwildtypeandmutanthraswithamemeticcellularandmultiscaleevolutionaryalgorithm
AT buyongma mappingtheconformationspaceofwildtypeandmutanthraswithamemeticcellularandmultiscaleevolutionaryalgorithm
AT ruthnussinov mappingtheconformationspaceofwildtypeandmutanthraswithamemeticcellularandmultiscaleevolutionaryalgorithm
AT amardashehu mappingtheconformationspaceofwildtypeandmutanthraswithamemeticcellularandmultiscaleevolutionaryalgorithm