Affiliations: Genome Technology Branch, National Human Genome
Research Institute, National Institutes of Health, Bethesda, Maryland 20892,
USA, e-mail: [email protected] | Computational Biology Branch, National Center for
Biotechnology Information, National Library of Medicine, National Institutes of
Health, Bethesda, Maryland 20894, USA, e-mail: [email protected]
Note: [] corresponding author
Abstract: Biochemical studies to date have not been able to identify the
linker histone H1 protein in the budding yeast Saccharomyces cerevisiae.
Database homology searching against the complete yeast genome has identified a
gene, HHO1, (or YPL127C, formerly LPI17) which encodes a protein that has two
regions that show similarity to the pea histone H1 globular domain. To
determine whether Hho1p can assume the shape of an H1 protein, homology model
building experiments were performed using the structure of chicken histone H5
globular domain as the basis for comparison. A statistically significant match
between each of the two globular domains of Hho1p and the chicken histone H5
structure was obtained, and probability values indicate that there is a less
than 1 in 100 chance that such a match would be the result of a random event.
These findings support the proposal that Hho1p acts as an "H1 dimer" and could
be responsible for the decreased linker DNA length observed between nucleosomal
core particles.
Keywords: histone H1, HHO1, homology model building, protein structure prediction
