Analysis of Alternative Splicing in Drosophila Genetic Mosaics

Many studies on alternative pre-mRNA splicing are carried out in cell-free systems or in cultured cells grown under nonphysiological conditions. The introduction of splicing reporter genes into the genomes of model organisms offers a way to investigate the functions of splicing regulators in the context of living organisms. This permits the direct study of alternative splicing (AS) events that change during development, aging, and in response to environmental conditions. In these systems, powerful genetic tools can be employed to analyze splicing factor function, including conditional expression, targeted mutations, and RNA interference. In this chapter, an approach is presented that utilizes Drosophila genetic mosaics in combination with splicing reporters to visualize how alterations in splicing factor function affect splice site selection in vivo.