Protein Complex Analysis
Protein Complex Analysis - Related Videos
02:41
Protein Complex Assembly
0 Views •
2020
Proteins can form homomeric complexes with another unit of the same protein or heteromeric complexes with different types. Most protein complexes self-assemble spontaneously via ordered pathways, while some proteins need assembly factors that guide their proper assembly. Despite the crowded intracellular environment, proteins usually interact with their correct partners and form functional complexes. Many viruses self-assemble into a fully functional unit using the infected host cell to...
01:57
Protein Complexes with Interchangeable Parts
0 Views •
2020
Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct. The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
05:13
Isolation of Proteins from Viral DNA-protein Complexes
0 Views •
2026
Source: Dembowski, J. A., et al. Purification of Viral DNA for the Identification of Associated Viral and Cellular Proteins. J. Vis. Exp. (2017).This video demonstrates the isolation of protein–viral DNA complexes from cell nuclei using click chemistry and magnetic bead purification. The protocol involves labeling viral genomes with alkyne-modified nucleotides, biotinylation via a click reaction, and binding to streptavidin-coated magnetic beads. Following washing and heat elution, the purified...
16:40
T-wave Ion Mobility-mass Spectrometry: Basic Experimental Procedures for Protein Complex Analysis
0 Views •
Cited by 51 •
2010
Ion mobility-mass spectrometry is an emerging gas-phase technology that separates ions, based on their collision cross-section and mass. The method provides three-dimensional information on the overall topology and shape of protein complexes. Here, we outline a basic procedure for instrument setting and optimization, calibration of drift times, and data interpretation.
15:35
Analyzing Large Protein Complexes by Structural Mass Spectrometry
0 Views •
Cited by 68 •
2010
Mass spectrometry has proven to be a valuable tool for analyzing large protein complexes. This method enables insights into the composition, stoichiometry and overall architecture of multi-subunit assemblies. Here, we describe, step-by-step, how to perform a structural mass spectrometry analysis, and characterize macromolecular structures.
FAQs
Native conditions help preserve protein assemblies and their associated partners during isolation. This is important because disrupting the complex before analysis could obscure which proteins function together. Maintaining the assembly allows researchers to examine complex composition more faithfully and relate detected interactions to cellular organization, regulation, or organelle function.
Both approaches isolate a target protein together with associated proteins, but they do so through different targeting strategies. Affinity purification captures the target using an affinity-based interaction, whereas immunoprecipitation uses an antibody-directed approach. The recovered material can then be examined to determine which partners were present in the isolated complex.
Differences in the proteins associated with a complex can reflect changes caused by mutations, signaling, or disease. Comparing complex composition under different biological conditions may therefore reveal regulatory mechanisms or altered interaction networks. These patterns help connect molecular changes in protein assemblies with broader effects on cellular organization and phenotype.
A typical workflow preserves the complex under native conditions, isolates a target protein with its associated partners, and identifies the recovered components. Researchers may use affinity purification or immunoprecipitation for isolation, followed by mass spectrometry or gel electrophoresis for component analysis. The resulting information can be interpreted as part of an interaction network.
Mass spectrometry and gel electrophoresis provide complementary ways to examine isolated complex material. In the described workflow, both techniques can support identification of the proteins recovered with a target. Their results help determine complex composition, which can then be used to investigate interaction networks, regulatory mechanisms, or condition-dependent changes.
This approach is useful when researchers need to connect molecular interactions with cellular functions. Applications include studying enzyme assemblies, transcriptional regulation, organelle function, and therapeutic targets. By examining which proteins occur together and how composition changes with mutations, signaling, or disease, investigators can relate complex organization to cellular phenotypes.