Figure 1

Isolation of CalpA and CalpB alleles. (A) Genomic organization of the CalpA locus at cytological position 56D5. The position of the CalpA^KG05080 P-element, inserted 948 bp upstream from the CalpA translation initiation site, is indicated. The breakpoints and the sizes of the CalpA⁸⁰⁸ and the Df(2R)ED3716^CG2 deficiencies are shown at the bottom. The boxes represent exons in the gene and in the primary transcripts. (B) RT-PCR detects CalpA mRNA in the w¹¹¹⁸ control strain and in the P{SUPor-P}CalpA^KG05080 insertion line but not in the CalpA⁸⁰⁸/Df(2R)ED3716^CG2 transheterozygotes. Arrows indicate wild-type genomic and complementary DNA RT-PCR fragments. (C) Western blotting of adult whole fly extracts reveals CalpA protein in the w¹¹¹⁸ control strain and in the P{SUPor-P}CalpA^KG05080 insertion line but not in the CalpA⁸⁰⁸/Df(2R)ED3716^CG2 transheterozygotes. The lower panel shows loading controls; the arrows mark the positions of CalpA and α-actin bands. (D) Genomic organization of the CalpB locus at cytological position 67D1. The location of the CalpB^EY08042 P-element, inserted 175 bp upstream from CalpB ATG, is indicated. The breakpoints and the sizes of the CalpB⁵⁰⁵ and CalpB³⁶¹ deficiencies are shown at the bottom together with the size of the CBG²⁶ genomic DNA fragment used for the rescue of the mutant phenotypes. The boxes indicate the exons in the primary transcript. (E) RT-PCR reveals the presence of truncated CalpB mRNA in the CalpB⁵⁰⁵ and CalpB³⁶¹ homozygotes. The calculated sizes of the PCR products are designated by the arrows on the right. (F) No CalpB-specific signals can be detected in the extracts from adult CalpB⁵⁰⁵ homozygous mutants by Western blotting. The arrows denote the positions of the full length 110 kDa CalpB in the upper panel, and the α-actin loading control bands in the lower panel, respectively.