Artificial transcription factors as tools for gene expression manipulation / 生物工程学报

ABSTRACT

In this new era of the genome, the complete sequences of various organisms (from the simplest to the most complex such as human) are now available, which provides new opportunities to study biology and to develop therapeutic strategies. But the paucity of research tools that manipulate specific genes in vivo represents a major limitation of functional genomic studies. In nature, the expression of genes is regulated at the transcriptional level primarily by proteins that bind to nucleic acids. Many of these proteins, which are termed transcription factors, are typically consist of two essential yet separable modules DNA-binding domain (DBD) and effector domain (ED). Attempts to control the gene expression by artificial transcription factors are based on the application of this rule. Among the many naturally occurring DNA-binding domains, the Cys2-His2 zinc-finger domain has demonstrated the greatest potential for the design of novel sequence-specific DNA-binding proteins. Each zinc finger domain, which comprises about 30 amino acids that adopt a compact structure by chelating a zinc ion, typically functions by binding 3 base pairs of DNA sequence. Several zinc fingers linked together would bind proportionally longer DNA sequences. Ideally, these artificial DNA binding proteins could be designed to specifically target and regulate one single gene within a genome as complex as that found in human. Such proteins would be powerful tools in basic and applied research.