You have identified an enhancer trap line (see Figure 14.17) generated by P element transposition in Drosophila in which the marker gene from the enhancer trap is specifically expressed in the wing imaginal disc.

How would you show that the expression pattern of the enhancer trap line reflects the endogenous gene expression pattern of the adjacent gene?

Verified step by step guidance

1. <Identify the adjacent gene to the enhancer trap insertion site using molecular techniques such as inverse PCR or genome sequencing.>
2. <Analyze the expression pattern of the adjacent gene using in situ hybridization or RT-PCR to determine its expression in the wing imaginal disc.>
3. <Compare the expression pattern of the adjacent gene with the expression pattern of the marker gene from the enhancer trap line in the wing imaginal disc.>
4. <Perform a genetic complementation test by creating a mutant allele of the adjacent gene and observing if the enhancer trap line rescues the mutant phenotype.>
5. <Use reporter gene assays to confirm that the regulatory elements driving the expression of the marker gene are the same as those driving the expression of the adjacent gene.>

Key Concepts

Enhancer Traps

Enhancer traps are genetic tools used to study gene expression patterns. They consist of a reporter gene that is activated by nearby enhancers, allowing researchers to visualize where and when specific genes are expressed. In Drosophila, enhancer traps can help identify regulatory elements that control gene expression in various tissues, such as the wing imaginal disc.

Gene Expression Patterns

Gene expression patterns refer to the spatial and temporal expression of genes within an organism. These patterns are crucial for understanding developmental processes and tissue differentiation. By comparing the expression of the enhancer trap marker with the expression of the adjacent endogenous gene, researchers can determine if the enhancer trap accurately reflects the natural expression pattern of that gene.

In Situ Hybridization

In situ hybridization is a technique used to detect specific RNA sequences within fixed tissues or cells. This method allows researchers to visualize the localization of gene expression at the cellular level. By applying in situ hybridization to both the enhancer trap and the adjacent gene, one can compare their expression patterns directly, providing evidence that the enhancer trap reflects the endogenous gene's expression.