Budget Amount *help |
¥12,200,000 (Direct Cost: ¥12,200,000)
Fiscal Year 1999: ¥5,200,000 (Direct Cost: ¥5,200,000)
Fiscal Year 1998: ¥7,000,000 (Direct Cost: ¥7,000,000)
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Research Abstract |
On the basis of the DNA recognition mode and the structural features unique to the CysィイD22ィエD2-HisィイD22ィエD2 class of nucleic acid binding, approaches to link CysィイD22ィエD2-HisィイD22ィエD2 zinc fingers with other functional modules such as DNA binding domains to generate artificial chimeric peptides with long binding sites, and DNA-cleavage modules to produce novel sequence specific nucleases, ィイD14-5ィエD1 have been performed. Statistically, assuming random base distribution, a unique 16-or 18-base pair sequence will occur only once in 4.3 billion or 68 billion nucleotides, roughly the same or big size of a human genome. Although natural proteins containing long polydactyl arrayl arrays of zinc finger do-mains have been inferred from sequence, no zinc finger proteins have been demonstrated to bind such a long, contiguous DNA sequence. Therefore, it is of special interest that six-or nine-fingered peptide was created and demonstrated to bind 18 or 27 contiguous base pairs of DNA in a sequence specific fashion. An artificial protein that induces a DNA conformational change is interesting as a transcriptional regulator of a specific gene. We created 6-zinc finger proteins, Sp1ZF6(Gly)n(n=4,7,10), by connecting two DNA binding domains of transcription factor Sp1 with flexible polyglycine peptide linkers, and their effects on DNA structure were compared with that of native 3-zinc finger Sp1(530-623). Of special interest are the fact that newly designed 6-finger peptides Sp1ZF(Gly)7 and Sp1ZF(Gly)10 can induce DNA bending at the intervening region of the two distal binding sites and that the liker length between two 3-zinc finger motifs has a crucial effect on the entire DNA bending direction. Such polydactyl zinc finger peptides should be the development of novel transgenic plants and animals.
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