Fig. 1.

Drosophila HPat alleles and antibodies. (A) Diagram of the hpat gene showing intron and exon boundaries. Also shown are the insertion sites for two P elements (hpat^EY10289 and hpat^l(3)0442) in the hpat 5′ UTR and the region targeted by the hpat antisense in situ construct. In hpat^d3 and hpat^d17, deletions occurred within the hpat^EY10289 P element such that the hpat coding sequence was unaffected. Instead, the size of the P element inserted into the hpat 5′ UTR was reduced. hpat^15p is a precise excision of hpat^EY10289. (B) Diagram of the hpat gene region. Shown are sequences included in the P21M20 rescue transgene and missing from the Df(3R)Exel8165 deficiency. (C) Western blot showing HPat expression levels in extract from whole w¹¹¹⁸, hpat^d3 and hpat^EY10289 homozygous larvae. Rabbit HPat antibodies recognize 108 kDa and 102 kDa bands corresponding to two predicted isoforms. Both bands are significantly reduced in hpat^d3 mutants and almost eliminated in hpat^EY10289 homozygotes. Smaller bands in the w¹¹¹⁸ control and hpat mutants are likely proteolytic fragments of the HPat protein.