Division of Tumor Virology, Dana-Farber Cancer Institute, Boston, MA.
Proc Natl Acad Sci U S A 87: 9459-63 (1990)
Abstract
Two regions of the Epstein-Barr virus (EBV) BZLF1 gene product, ZEBRA,
share sequence homology with c-Fos, one of which corresponds to the DNA
binding domain of c-Fos. ZEBRA does not, however, contain the heptad
repeat of leucines present in the dimerization domains of leucine zipper
proteins. Here it is shown that ZEBRA binds its recognition sites as a
homodimer and that the region adjacent to the basic DNA binding domain
is essential for dimerization. This region contains a 4-3 repeat of
predominantly hydrophobic residues, which is precisely in register with
the hydrophobic heptad repeat present in the leucine zipper proteins
with respect to the basic DNA binding domain. A mutational analysis of
ZEBRA supports a model for dimerization involving a coiled-coil
interaction. These results indicate that a heptad repeat of leucines is
not a structural requirement for formation of coiled-coil dimers by
transcription factors.
Mesh Headings
Unique Identifier: 91067725
Gene Symbols
Chemical Identifiers (Names)