Homeobox genes are referred to as a group of genes responsible for regulating the development of multicellular organisms including plants and animals. The forms of development include differentiation of cells as well as cell morphogenesis. Homeobox genes can be found in several organisms including animals as well as plants. Slime molds also possess homeobox genes. Homeobox genes can be categorized into several classes on the basis of their conserved structure of intron-exon as well as their unique codomain architectures. According to the research, after analyzing ten genomes from flowering plants as well as an alga, a complete complement of sequences of homeobox transcription factor was established.
Homeotic genes:
DNA (Deoxyribonucleic acid) contains genes that regulate morphogenesis; these genes are called homeotic genes. The subset of homeotic genes is called homeobox having 180 base pair length of DNA. Homeotic genes are also referred to as selector genes and are responsible for the identification of a particular organ, structure of the body. Homeotic genes organize the shape of organisms. The Homeobox gene has a 180 base pair long DNA strand within and is called homeobox. Homeobox sequence is a highly conserved sequence of a gene, is present not only in animals but plants and fungi also, as it remained unchanged during the process of evolution of different species. The homeobox sequence codes for a 60 amino acid residues sequence within the protein that has been synthesized and is called homeodomain. Homeodomain sequences then fold into 3-helix specific shape. The second and third helix is connected by amino acid loops forming a helix-turn-helix organization.
This helix-turn-helix arrangement allows the protein to bind with DNA and regulate the transcription of the genes present nearby. The proteins that contain the homeodomain are called transcription factors. The subset of homeobox genes is called Hox genes.