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Genome-wide Protein-protein Interaction Screening by Protein-fragment Complementation Assay (PCA) in Living Cells
Published on: March 3, 2015
A technique to search for functional similarities in protein-protein interaction networks
Valeria Fionda1, Luigi Palopoli, Simona Panni
1Department of Mathematics, University of Calabria, Rende (CS), Italy. fionda@si.deis.unical.it
International Journal of Data Mining and Bioinformatics
|January 8, 2010
Summary
This study introduces a novel method for comparing protein-protein interaction networks across species. The technique effectively identifies functional orthologs and common biological processes, even for uncharacterized proteins.
Area of Science:
- Computational Biology
- Bioinformatics
- Systems Biology
Background:
- Protein-protein interaction (PPI) networks are crucial for understanding cellular mechanisms.
- Comparing PPI networks across different organisms can reveal conserved biological functions and evolutionary relationships.
- Existing methods often struggle to detect functional similarities when sequence homology is low.
Purpose of the Study:
- To develop and validate a computational method for identifying similarities between PPI networks of distinct species.
- To leverage quantitative and reliability information within PPI data for enhanced network comparison.
- To uncover functional orthologs and common biological processes, particularly for proteins with limited sequence similarity.
Main Methods:
- The core technique involves constructing bipartite graphs by comparing protein neighborhoods across different organisms' PPI networks.
- A maximum weight matching algorithm is applied to these bipartite graphs to identify conserved interaction patterns.
- The method incorporates both quantitative interaction data and reliability scores.
Main Results:
- The approach successfully detected functional orthologs in the PPI networks of *Saccharomyces cerevisiae*, *Drosophila melanogaster*, and *Caenorhabditis elegans*.
- The method proved effective in identifying conserved biological processes involving uncharacterized proteins, outperforming methods relying solely on sequence similarity.
- Experimental results demonstrate the robustness and applicability of the network comparison technique.
Conclusions:
- The developed method provides a powerful tool for cross-species PPI network analysis.
- It enhances the discovery of functional relationships and conserved pathways, especially in the context of limited sequence information.
- This approach facilitates a deeper understanding of protein function and biological system evolution.
Related Concept Videos
02:26Protein Networks
An organism can have thousands of different proteins, and these proteins must cooperate to ensure the health of an organism. Proteins bind to other proteins and form complexes to carry out their functions. Many proteins interact with multiple other proteins creating a complex network of protein interactions.
These interactions can be represented through maps depicting protein-protein interaction networks, represented as nodes and edges. Nodes are circles that are representative of a protein,...
These interactions can be represented through maps depicting protein-protein interaction networks, represented as nodes and edges. Nodes are circles that are representative of a protein,...
02:26Protein Networks
An organism can have thousands of different proteins, and these proteins must cooperate to ensure the health of an organism. Proteins bind to other proteins and form complexes to carry out their functions. Many proteins interact with multiple other proteins creating a complex network of protein interactions.
These interactions can be represented through maps depicting protein-protein interaction networks, represented as nodes and edges. Nodes are circles that are representative of a protein,...
These interactions can be represented through maps depicting protein-protein interaction networks, represented as nodes and edges. Nodes are circles that are representative of a protein,...
02:04Protein-protein Interfaces
Many proteins form complexes to carry out their functions, making protein-protein interactions (PPIs) essential for an organism's survival. Most PPIs are stabilized by numerous weak noncovalent chemical forces. The physical shape of the interfaces determines the way two proteins interact. Many globular proteins have closely-matching shapes on their surfaces, which form a large number of weak bonds. Additionally, many PPIs occur between two helices or between a surface cleft and a polypeptide...
02:04Protein-Protein Interfaces
Many proteins form complexes to carry out their functions, making protein-protein interactions (PPIs) essential for an organism's survival. Most PPIs are stabilized by numerous weak noncovalent chemical forces. The physical shape of the interfaces determines the way two proteins interact. Many globular proteins have closely-matching shapes on their surfaces, which form a large number of weak bonds. Additionally, many PPIs occur between two helices or between a surface cleft and a polypeptide...
02:47Protein Families
Protein families are groups of homologous proteins; that is, they have similarities in amino acid sequences and three-dimensional structures. Protein families usually occur because of gene duplication, where an additional copy of a gene is inserted into the genome of an organism. Mutations that change the amino acids but still allow the protein to be properly synthesized, will lead to new protein family members. If these new proteins contain similar amino acids in key locations, protein...
01:49Conserved Binding Sites
Many proteins’ biological role depends on their interactions with their ligands, small molecules that bind to specific locations on the protein known as ligand-binding sites. Ligand-binding sites are often conserved among homologous proteins as these sites are critical for protein function.
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally analyses the...
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally analyses the...