Related Experiment Videos
Ionic strength induced structure in histone H4 and its fragments
Biochemistry
|July 29, 1975
Summary
Histone H4 undergoes salt-induced folding and self-association, forming alpha-helices and beta-structures. The critical region for this process in histone H4 is identified as fragment (25-67).
Area of Science:
- Biochemistry
- Structural Biology
- Biophysics
Background:
- Histone H4 is a key component of chromatin.
- Understanding histone folding and self-association is crucial for comprehending DNA packaging and gene regulation.
Purpose of the Study:
- To investigate the salt-induced folding and self-association of intact histone H4 and its specific fragments.
- To identify the critical region within histone H4 responsible for its structural changes and aggregation.
Main Methods:
- Nuclear Magnetic Resonance (NMR) spectroscopy
- Circular Dichroism (CD) spectroscopy
- Infrared (IR) spectroscopy
Main Results:
- Intact histone H4 showed rapid alpha-helix formation and aggregation, followed by slower beta-structure formation.
- Fragment (25-67) mimicked the fast structural changes (helix formation, aggregation) of intact histone H4 but lacked time-dependent effects.
- Other histone H4 fragments exhibited minimal interaction.
Conclusions:
- Fragment (25-67) contains the critical region for histone H4 folding and self-association.
- A model proposes alpha-helix formation between residues 49-73 and beta-structure formation between residues 74-C-terminus in histone H4 self-association.