The apterous gene in Drosophila encodes a protein required for wing patterning and growth. It is also known to function in nerve development, fertility, and viability. When human and mouse genes whose protein products closely resemble apterous were used to generate transgenic Drosophila [Rincon-Limas et al. (1999). Proc. Nat. Acad. Sci. (USA) 96:2165–2170], the apterous mutant phenotype was rescued. In addition, the whole-body expression patterns in the transgenic Drosophila were similar to normal apterous.

What is meant by the term rescued in this context?

Verified step by step guidance

1. Identify the context in which the term 'rescued' is used, which is in genetic experiments involving transgenic organisms.
2. Understand that 'rescue' in genetics refers to the restoration of a normal phenotype in an organism that has a mutant phenotype due to a defective gene.
3. Recognize that in this scenario, the apterous gene in Drosophila is mutated, leading to a mutant phenotype affecting wing patterning, nerve development, fertility, and viability.
4. Note that the introduction of human and mouse genes, which produce proteins similar to the apterous protein, into the mutant Drosophila results in the restoration of normal wing patterning and other functions.
5. Conclude that 'rescued' means the transgenic Drosophila exhibit normal phenotypes similar to those with a functional apterous gene, indicating the introduced genes compensate for the defective gene.

Key Concepts

Gene Function and Phenotype

In genetics, a gene's function refers to the specific biological role it plays in an organism, often influencing traits or characteristics, known as phenotypes. The apterous gene in Drosophila is crucial for wing development and other physiological processes. When a gene is mutated, it can lead to a phenotype that deviates from the norm, such as the apterous mutant phenotype, which lacks proper wing formation.

Transgenic Organisms

Transgenic organisms are those that have been genetically modified to contain genes from other species. In this case, human and mouse genes similar to the apterous gene were introduced into Drosophila. This technique allows researchers to study gene function and the effects of specific proteins on development and physiology, providing insights into genetic rescue and functional conservation across species.

Genetic Rescue

Genetic rescue refers to the process by which the introduction of a functional gene can restore normal phenotype or function in an organism with a genetic mutation. In the context of the apterous gene, the introduction of similar genes from humans and mice into the Drosophila resulted in the restoration of normal wing development, effectively 'rescuing' the mutant phenotype. This demonstrates the conservation of genetic functions across different species.