Figure 1.
The nrc mutation is a stop codon in synj1, and Synj1 is expressed in brain and retina. A, Positional cloning defines the critical genetic region for the nrc mutation. The number between genetic markers represents the number of recombinants identified. B, Schematic of Synj1 domains, SacI (Sac1), 5′-phosphatase (5′Ptase), and proline-rich protein binding domain (pppp). The site of the nrc mutation is shown as a stop on the domain schematic. DNA sequence wave data of the mutation site reveals C to T nonsense mutation in nrc larvae. The full-length protein sequence of zebrafish Synj1 is shown with the mutation site demarcated in red. The border between phosphatase domains is marked by a bold line. The green rectangle demarcates the putative clathrin-binding domain. The putative amphiphysin-binding domain is outlined by a blue rectangle, and the endophilin-binding domain is demarcated by a red rectangle. C, Antisense, but not sense, RNA in situ hybridization reveals synj1 in WT 6 dpf larval brain. The arrowheads point to the brain region. D, Two-week-old mouse retinal section immunohistochemistry with anti-Synj1 proline-rich domain antibody localizes Synj1 to the OPL and IPL. Scale bar, 50 μm. E, Dendrogram shows the amino acid conservation between zebrafish Synj1 and other previously published Synjs. Zebrafish (Zf) Synj1 is more similar to human and rat Synj1 than to human (Hum) and rat Synj2. Dros, Drosophila. The dendrogram was generated using Vector Nti version 9.0 (Informax, Bethesda, MD). The GenBank accession number for zebrafish synaptojanin is AY736013.