Related Experiment Video
Updated: Jun 29, 2026

Method to Visualize and Analyze Membrane Interacting Proteins by Transmission Electron Microscopy
Published on: March 5, 2017
Localization and analysis of nonpolar regions in onconase
E Y Kolbanovskaya1, A C Terwisscha van Scheltinga, V G Mukhortov
1Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow.
Abstract:
A detailed analysis of the composition and properties of hydrophobic nuclei and microclusters has been carried out for onconase. Two main hydrophobic nuclei in the onconase structure were detected. Their composition and shape were found to be very similar to those of RNase A, in accordance with the predictions made. The nuclei in onconase are more compact, the side-chain atoms of residues included in the nuclei in onconase form more contacts with the environment than in RNase A. The hydrophobic nuclei should be considered as individual structural units along with elements of the secondary structure. Differences in composition and conformation of exposed loops between onconase and RNase A were found. The additional hydrophobic clusters attached to the nuclei in onconase might be involved in the fixation of an appropriate conformation of site(s) for manifestation of the biological activity of onconase. A comparison of amphibian representatives of the RNase A superfamily was also made. The results obtained suggest that the availability of nonpolar residues in established key positions of amino acid sequences determines the characteristic fold of homologous proteins and the structure of the active site cleft.
More Related Videos
Related Concept Videos
Molecular Shape and Polarity
Conserved Binding Sites
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...
Nuclear Localization Signals and Import
Nuclear Overhauser Enhancement (NOE)
Western Blotting
The technique begins with separating proteins from the sample using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), followed by protein transfer, immunoblotting, and finally, protein detection.
Insensitive Nuclei Enhanced by Polarization Transfer (INEPT)

