Tramtrack protein-DNA interactions. A cross-linking study.

D E Kamashev; A V Balandina; V L Karpov

doi:10.1074/jbc.m001691200

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Tramtrack protein-DNA interactions. A cross-linking study.

D E Kamashev·A V Balandina·V L Karpov

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Abstract

Interaction of the Tramtrack protein from Drosophila melanogaster with DNA was analyzed by a cross-linking method. Tramtrack residues cross-linkable to the partially depurinated DNA were identified by direct sequencing. The N-terminal alpha-amino group of the protein DNA-binding domain was found to be the major product of cross-linking. The location of the N terminus on the DNA was determined by identification of the DNA bases that were cross-linked to the protein alpha-amino group. We conclude that accessory N-terminal peptide preceding the first zinc finger of Tramtrack directly interacts with DNA, both in specific and nonspecific DNA-protein complexes. Our finding explains the role in the protein binding of the DNA bases outside of the direct interaction with the zinc fingers.

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Amino Acid Sequence Animals Base Sequence Binding Sites Cross-Linking Reagents DNA DNA-Binding Proteins Drosophila Proteins Drosophila melanogaster Exonucleases Protein Binding Protein Structure, Tertiary Repressor Proteins Substrate Specificity Trypsin Zinc Fingers Journal Article Research Support, Non-U.S. Gov't

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D E Kamashev, A V Balandina, V L Karpov. 2000-11-17. Tramtrack protein-DNA interactions. A cross-linking study.. https://doi.org/10.1074/jbc.m001691200

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