Prothymosin alpha modulates the interaction of histone H1 with chromatin.
AUTOR(ES)
Karetsou, Z
RESUMO
Prothymosin alpha (ProTalpha) is an abundant acidic nuclear protein that may be involved in cell proliferation. In our search for its cellular partners, we have recently found that ProTalpha binds to linker histone H1. We now provide further evidence for the physiological relevance of this interaction by immunoisolation of a histone H1-ProTalpha complex from NIH 3T3 cell extracts. A detailed analysis of the interaction between the two proteins suggests contacts between the acidic region of ProTalpha and histone H1. In the context of a physiological chromatin reconstitution reaction, the presence of ProTalpha does not affect incorporation of an amount of histone H1 sufficient to increase the nucleosome repeat length by 20 bp, but prevents association of all further H1. Consistent with this finding, a fraction of histone H1 is released when H1-containing chromatin is challenged with ProTalpha. These results imply at least two different interaction modes of H1 with chromatin, which can be distinguished by their sensitivity to ProTalpha. The properties of ProTalpha suggest a role in fine tuning the stoichiometry and/or mode of interaction of H1 with chromatin.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=147683Documentos Relacionados
- Histone H1 deposition and histone-DNA interactions in replicating chromatin.
- Influence of histone H1 on the in vitro replication of DNA and chromatin.
- A lysine-rich protein functions as an H1 histone in Dictyostelium discoideum chromatin.
- Cooperative interaction of histone H1 with DNA.
- Influence of histone acetylation on the solubility, H1 content and DNase I sensitivity of newly assembled chromatin.
