Question

Written answer/problems. Type the full answer to each part of the question

Describe the characteristics that are similar between the Drosophila homeotic genes and the mammalian Hox genes. Be sure to include the general functions of the proteins these genes encode.

Answer 1

• Homeotic genes are master regulator genes that direct the development of particular body segments or structures.

• When homeotic genes are overactivated or inactivated by mutations, body structures may develop in the wrong place—sometimes dramatically so!

• Most animal homeotic genes encode transcription factor proteins that contain a region called the homeodomain and are called Hox genes.

• Hox genes are turned on by a cascade of regulatory genes; the proteins encoded by early genes regulate the expression of later genes.

• Hox genes are found in many animals, including fruit flies, mice, and humans. Mutations in human Hox genes can cause genetic disorders.