Bd. Dynlacht et al., DNA-BINDING AND TRANSACTIVATION PROPERTIES OF DROSOPHILA E2F AND DP PROTEINS, Proceedings of the National Academy of Sciences of the United Statesof America, 91(14), 1994, pp. 6359-6363
The temporal activation of E2F transcriptional activity appears to be
an important component of the mechanisms that prepare mammalian cells
for DNA replication. Regulation of E2F activity appears to be a highly
complex process, and the dissection of the E2F pathway will be greatl
y facilitated by the ability to use genetic approaches. We report the
isolation of two Drosophila genes that can stimulate E2F-dependent tra
nscription in Drosophila cells. One of these genes, dE2F, contains thr
ee domains that are highly conserved in the human homologs E2F-1, E2F-
2, and E2F-3. Interestingly, one of these domains is highly homologous
to the retinoblastoma protein (RB)-binding sequences of human E2F gen
es, The other gene, dDP, is closely related to the human DP-1 and DP-2
genes. We demonstrate that dDP and dE2F interact and cooperate to giv
e sequence-specific DNA binding and optimal trans-activation. These fe
atures suggest that endogenous Drosophila E2F, like human E2F, may be
composed of het erodimers and may be regulated by RB-Like proteins. Th
e isolation of these genes will provide important reagents for the gen
etic analysis of the E2F pathway.