Hairless

Hairless, also known as H, is a well-characterized Drosophila gene. Many mutations to hairless are embryonic lethal; however, there are several viable hairless mutants. Hairless is involved in the Notch signaling pathway in Drosophila, acting as a suppressor of Notch signaling.
Hairless (H) encodes a hydrophilic protein. The protein is composed of 1076 amino acids, with a molecular weight of 110 kDa. The H protein is reported in insects and is found in nearly all of the family Drosophilidae. The H protein is also found in the family Culicidae as well as the orders Lepidoptera, Hymenoptera and Coleoptera. 
In "Drosophilia", NSP, or notch signaling pathway, allows for communication intercellularly during embryo development and also physiological activities of adult organisms. Their research also states that Notch Signaling Pathways turn on periodically during devolvement to help determine cell fate functions of the cell. Hairless (H) is an antagonist of the NSP as well as a “key member of the Su[H] repressor complex." Because of this connection, Hairless plays a very important part of embryo development in insects as it helps influence cell fate decisions during this time." It is crucial that proteins, HP120 and HP150, are present as they control normal activity of H. This activity regulation also controls NSP, which allows the fly embryos to develop correctly and any fluctuation in the pathway or proteins can change outcome of the offspring.