Histone interaction

The histones interact with each other in very specific ways. H3 and H4 form a tetramer containing two mol-... 

B. In Vivo Studies of Histone-Histone Interactions and Contacts. 9... 

C. Histone-Histone Interactions in Salt-Dissociated Chromatin. 12... 

During the course of the article, we will present evidence that the histones constitute part of a self-assembly system (Section IV). In the absence of DNA they retain the information to interact with each other to form a hierarchy of structures with dimensions, periodicities, and intermolecular contacts, compatible with what is known about the protein core of chromatin. This strongly suggests that histone-histone interactions have a fundamental role in chromatin structure. 

Hyde and Walker, 1975a) indicate that there are two basic types of histone-histone interactions or contacts those within the nucleosome which result in the formation of histone octamers and those between nucleosomes which give rise to higher oligomers. 

D. Histone -Histone Interaction in Vitro 1. Histone Pairs... 

Although the quantitation of the cross-linking data is limited, as discussed above, comparison of the cross-linked histones obtained from chromatin with histone complexes obtained in the absence of DNA can help in developing a more detailed picture of histone-histone interactions. An H2A-H2B dimer was obtained by cross-linking of chromatin with short-range cross-linkers (for references, see Section... 

This may be correlated with the conservation of the primary sequences of the carboxy-terminal regions of the histones and the indications that these are the sites of histone-histone interaction within the nucleosomes (Spiker and Isenberg, 1978). 

B. DNA-Core Histone Interactions Involved in Formation of the Nucleosome... 

Abstract Histone chaperones are the histone interacting factors that stimulate histone transfer... 

It is not widely appreciated that the major aspects of core histone interactions were well understood even before the development of the nucleosome model. Evidence for strong H2A H2B dimer interactions and an FI3 H4 tetramer was available in the early seventies (see Ref. [1], Chapter 2). By 1978, the rigorous sedimentation equilibrium studies from Moudrianakis laboratory had elucidated the thermodynamics of octamer formation [7]. What was missing, of course, was any structural information concerning these interactions. This was overcome by arduous X-ray diffraction studies, culminating in the elegantly detailed structures we have today [15,17,18], see also Flarp et al., this volume, p. 13. We now know how the core... 

Fig. 20. Packing interactions between NCP molecules, which are a consequence of crystallization, nevertheless provide hints for higher order chromatin structure assembly, (a) Histone-histone interactions shown at the site of the cacodylate ion. In addition to binding interactions with the cacodylate ion, the N-terminal tail is involved in significant interactions with the patch of acidic residues on the dimer face of the neighbor NCP. The orientation of the dyad alternates between the two NCP molecules, (b) DNA base stacking is continuous between neighboring NCP molecules in the crystal lattice as the DNA exits one NCP and enters the next. The stacking interaction is strong enough to force a shift in the terminal phosphates for adjoining 5 termini.

Glowczewski, L., Yang, P., Kalashtrikova, T., Santisteban, M.S., and Smith, M.M. (2000) Histone-histone interactions and centromere function. Mol. Cell. Biol. 20, 5700-5711. 

The temporal sequence of H3 and H4 methylation after synthesis has been examined in Ehrlich ascites tumor cells [144] and trout testis [149]. Methylation lagged histone synthesis, and the histone was methylated after being bound to DNA. H4 methylation follows the stepwise acetylations and deacetylations [149]. It was suggested that methylation was involved in final arrangement of H3 and H4 on newly replicated DNA [144] and might be involved in histone interactions with other proteins such as histone kinases [149]. 

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