A multiplex fluorescent in situ hybridization protocol for clonal analysis of Drosophila oogenesis.

Fluorescent in situ hybridization (FISH) is a common inmunohistochemical method used to examine the distribution of RNAs in tissue samples. In mosaic tissues composed of a mixed population of wild-type and loss-of- or gain-of-function mutant cells, FISH allows comparison of the effect of the perturbation on gene expression patterns in a mutant cell and its wild-type neighbors. Here, we provide a protocol for the detection of RNA in Drosophila mosaic follicular epithelia, where the mosaic analysis with a repressible cell marker (MARCM) technique is used for expression of transgenes.