| Abstract |
The zinc finger is a small independently folded DNA recognition motif found in many eykaryotic proteins. In order to analyze them a database of 577 zinc fingers, from 106 different proteins has been constructed and a program for statistical analysis of aligned sequences written. We also designed a three dimensional model for the CF2-DNA interaction based on the structure of the Zif268-DNA complex (Pavletich and Pabo, 1991). The previous one represents an excellent working model for the interactions between the zinc fingers and the DNA. The chorion transcription factor CF2 was isolated as a potentional transcriptional regulator of a chorion gene of Drosophila melanogaster. It is a zinc finger protein which is present in the nuceli of follicle cells which produce the chorion. Localized CF2 is not detected in the early embryo but appears during later embryonic stages (Hsu et al., 1992). The model of the CF2-DNA complex was of general interest because it predicts the modularity of finger-DNA interactions other than the known hydrogen bonding has been reported at the Zif268-DNA structure. The binding site of the CF2 protein is A/T rich DNA (5-GATTATATA-3) instead of the G/C rich DNA (5-GCGTGGGCG-3) of the Zif268 protein. The results showed apart of the well characterized pattern observed in the Zif268 structure, that additional specific contacts may be formed with bases of the secondary DNA strand. From statstical analysis of the zinc finger sequences the particular role of each amino acid was noted and clusters of correlated residues at critical positions (DNA base contact positions) were observed. The results of the theoretical model of the complex CF2- DNA cmbined with statistical analysis will help to understand the mechanism of how zinc fingers, where the structure is unknown interact with the DNA.
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Ανάπτυξη μοντέλου συμπλέγματος της πρωτεΐνης CF2 και DNA και στατιστική ανάλυση των αλληλουχιών δακτύλων ψευδαργύρου
