Figure 1. ald Mutants and Their Effects.

(A) An oocyte nucleus from a yw; ald^C3/ald^Exc23; pol female, showing DNA (white) and tubulin (red). There is complete progression past metaphase I arrest, the chromosomes have separated into two masses, and each mass possesses its own individualized tubulin spindle.

(B) A map of the ald locus showing the location of the mutants used in this paper. ald^Exc23: An incomplete excision of P{GS:13084} that leaves 130 nt from the 5′ end of the P element, inserted after the 14th nt of the 5′ UTR. This allele has good viability and fertility but high levels of NDJ and very low protein expression (see Figure 5B). ald¹: A single nucleotide change causing a hypomorphic missense mutation (R7H). ald^C3: A 9-codon deletion (Δ369–377) near the kinase active site, resulting in a semi-lethal allele similar to other ald null alleles. P{KG08013}^ExcAN6 (also referred to as Df(3R)AN6): An imprecise excision of a P element that was inserted in the large intron of the next downstream gene to ald, CG18212/alt [44]. This excision retains 3782 nt of the 5′ end of the P sequence, then deletes approximately 8 kb of sequence (red bar), from the rest of the 3′ end of the P element to 165 nt upstream of the ald transcription start site; 98 nt of exon 2 of ald is present, reversed, at the excision site. This excision deletes all of the ald and alt protein coding sequences; alt mutants alone were previously shown to have no detectable effect on meiosis [5].