Figure 5. Half pint loss of function affects M1 splicing but not dsx splicing in vivo. (A) RT-PCR analysis of M1 splicing in adult testis mRNA from various genotypes is shown. Primer locations are indicated by arrow the diagram. In w¹¹¹⁸ flies that are wild type for both tra2 and hfp, the M1 intron is retained in a majority of transcripts. Loss of function for either tra2 or hfp result in reduced M1 retention. tra2¹ and tra2^b are point mutations that do not alter the total amount of Tra2 mRNA. Df(hfp) corresponds to Df(3L)AR148 is a large deletion that spans the entire hfp gene. (B) Similar RT-PCR analysis was performed on dsx RNA from whole adult males (M) and females (F) of various genotypes. Three primers, as indicated by arrows in the diagram, were used together to amplify both male and female-specific splicing products of dsx. As expected mature male mRNA was detected in RNA from a loss-of-function tra2 mutant genotype, but was not found in females from either of two strong loss-of-function hfp mutant genotypes tested.