What does antennapedia gene do?
Antennapedia (abbreviated Antp) is a Hox gene first discovered in Drosophila which controls the formation of legs during development. Loss-of-function mutations in the regulatory region of this gene result in the development of the second leg pair into ectopic antennae.
Is antennapedia dominant or recessive?
Most of the early mutations were dominant – ie only one copy of the mutant gene is required to affect a transformation (e.g. Antennapedia: antenna-to-leg). Later, recessive mutations Antennapedia were discovered, which cause the reverse transformation (leg-to-antenna).
What happens when the gene antennapedia is expressed in the head of the fly?
It is known that overexpressing Antennapedia in the head induces antenna-to-leg as well as head-to-thorax transformation and eye reduction. At present, little is known about the exact molecular mechanism causing these phenotypes.
What happened to the fly with a Hox mutation?
In Drosophila, the fruit fly, a Hox mutation can produce profound changes–an extra pair of wings, for example, or a set of legs, instead of antennae, growing from the fly’s head. Humans have Hox genes too.
Which scientists discovered the gene antennapedia?
Gehring identified the homeobox in 1983, with the help of colleagues while isolating the Antennapedia (Antp) gene in fruit flies (Drosophila) at the University of Basel in Basel, Switzerland.
What is a homeodomain protein?
The homeodomain is a highly conserved 60‐amino‐acid protein domain that is encoded by the homeobox and is found in organisms as diverse as mammals, insects, plants and yeast. Homeodomains function as DNA binding domains and are found in many transcription factors that control development and cell fate decisions.
What is the antennapedia complex?
The Antennapedia complex (ANT-C) is one of two Hox gene complexes. Hox genes encode homeodomain transcription factors. ANT-C controls the identity of segments that contribute to the head and the anterior thorax. ANT-C homeotic genes show colinearity in their expression patterns with the exception of pb.
How do Hox genes affect the development of embryos?
The role of the Hox genes is to specify positional identity in the embryo rather than the development of any specific structure. These positional values are interpreted differently in different embryos to influence how the cells in a region develop into, for example, segments and appendages.
What happens to the body of a fruit fly if the Hox gene is altered in some way?
Homeotic mutations in fruit flies Homeotic genes are responsible for determining the identity of particular segments or structures of the body. So, when homeotic genes are inactivated or expressed in unusual locations due to mutations, they may cause body segments to take on new—and sometimes startling!
What is the Antennapedia complex?
How many Hox genes do fruit flies have?
eight Hox genes
As shown, in Drosophila there are eight Hox genes in a row, and the genes’ order within that row reflects their order of expression in the fly body.
What do Homeodomains do?
Homeodomains function as DNA binding domains and are found in many transcription factors that control development and cell fate decisions. Structurally, homeodomains are related to helix‐turn‐helix proteins of bacteria and consist of three α helices folded around a hydrophobic core and a flexible N‐terminal arm.