Fig. 1.

aln^z24 is a null mutation that regulates NC formation and encodes RNA polymerase II-associated factor 1 (Paf1). (A-E) 36 hpf wild-type and aln mutant embryos. Wild-type embryos (A) have pigmented melanophores lacking in embryos harboring combinations of aln mutant alleles: (B) homozygous for the aln^z12 deletion mutation, (C) transheterozygous for the aln^z12 and c4 deletions, (D) transheterozygous for the aln^z12 deletion and aln^z24 ENU-induced mutations, and (E) homozygous for the aln^z24 mutation. (F,G) crestin expression detected by whole-mount in situ hybridization in 24 hpf wild-type sibling (F) and aln^z24 mutant (G) embryos, indicating a complete absence of migrating trunk NC in aln^z24. Arrowheads indicate premigratory and migrating trunk NC. A-G are lateral views with anterior to the left. (H) Paf1 protein is not detected by immunoblot analysis in 36 hpf aln^z12 or aln^z24 mutant embryos, but is readily detected in wild-type control siblings. Immunoblot detection of pMAPK serves as a protein-loading control.