Fig. S2.

Gene structures for unc-73a, -b, and -e isoforms and the molecular lesions in various unc-73 alleles. u908 was isolated from our screen as a mutant having TRN morphological defects. u1007, u1031, u1032, and u1033 were created using CRISPR/Cas9-mediated genome editing in animals that carried the tiam-1(u914) allele (28). Guide RNAs were designed to target exon 2 to inactivate unc-73B and exon 21 to inactivate unc-73E. Frameshift-causing deletions in each of the two isoforms were identified by genotyping.