Transcription Factor Genes

Abstract

Transcription factor (TF) genes encode DNA-binding proteins. In all organisms, TFs play central roles in transcription by regulating gene expression. TFs are involved in a variety of biological processes, such as development and cell cycle control. TFs comprise one of the largest known groups of genes. In the human genome, approximately 8% of genes encode TFs. Many TFs involved in developmental processes are well conserved among a wide range of species. This conservation indicates that alterations in TF function are a likely source of phenotypic diversity among species. In addition, numerous human diseases are known to arise from mutations that dysregulate the regulatory system. For example, more than 30% of human developmental disorders are caused by mutations in TFs (Boyadjiev and Jabs, Clin Genet 57:253–266, 2000). Therefore, the structures of TFs and the mechanisms regulating gene expression are areas of great interest in the fields of evolutionary studies and biomedicine. In this chapter, we review the basic concepts of TF structures and the biological pro- cesses through which TFs control gene expression by binding target sequences. We will additionally introduce the evolutionary patterns of TF gene families. We will further discuss the results of recent studies that have used new techniques, such as chromatin immunoprecipitation sequencing (ChIP-seq) and network motifs.