A putative start codon for RFK-1 exists within AH36. (A) A DNA construct consisting of hph (a hygromycin resistance cassette) and the promoter for the N. crassa ccg-1 gene was used to make three transformation vectors: v199, v214, and v221. (B) Vector v199 replaces 133 bp of AH36 while fusing ccg-1(P) to a putative start codon at position 28,264. Vector v214 and v221 are nearly identical to v199, except that they change the start codon to ATGT and TAA, respectively. (C–F) Crosses were performed to determine the effect of each allele on spore killing. Images depict asci from the following crosses: (C) F2-26 × P15-53, (D) F2-26 × ISU-4557, (E) F2-26 × ISU-4576, and (F) F2-26 × ISU-4584. With respect to the image labels, v199∆, v214∆, and v221∆ are abbreviations of v199∆::hph-ccg-1(P)-ATG, v214∆::hph-ccg-1(P)-ATGT, and v221∆::hph-ccg-1(P)-TAA, respectively. B, black; W, white.