Homeobox genes: Structure and expression during development and regeneration

Molecular mechanisms controlling the most important biological functions are highly conservative, This phenomenon can be seen in homeobox genes, which encode the regulatory proteins controlling basic developmental processes. The homeobox was first described about ten years ago in Drosophila melanogaster as a highly conservative gene region with characteristic structure. Later, homologous consequences were observed in many eukaryotic genes found in organisms ranging from yeast to humans. Biochemical, biophysical, and genetic studies have proved irrefutably that the homeobox controls a DNA-binding domain that allows proteins containing this domain to exert regulatory functions. The decisive role played by homeobox genes during development has stimulated great interest among researchers in this superfamily of genes, At present, more than 300 homeobox genes have been identified in animals of various taxa and their number is constantly growing. This review summarizes the published data about the structure and functions of homeobox genes and their role in development and regeneration.