Figure 1

Figure 1

MTMR5 domain topology, pathogenic variants, and spatiotemporal expression pattern in zebrafish. (A) Human MTMR5 contains six functional domains: an N-terminal tripartite DENN domain [upstream DENN (a.a. 1–86), DENN (a.a. 129–311) and downstream DENN (a.a. 364–433)], an SBF2 domain (a.a. 543–765), a GRAM domain (a.a. 883–969), a catalytically inactive myotubularin-phosphatase domain (a.a. 1108–1533), a coiled-coil domain (CC, a.a. 1651–1665) and a C-terminal PH domain (a.a. 1763–1868). Of note, the domain topology of the MTMR5 protein is highly conserved between human and zebrafish. Pathogenic variants are found throughout the gene (for details, see Supplementary Table 1). Note: autism SD (spectrum disorders). (B) RT-PCR using total cDNA shows temporal expression pattern of zebrafish mtmr5 from 6 h post-fertilization (hpf) to 5 dpf (days post-fertilization). Note: ppib is a housekeeping control. (C) Whole-mount in situ hybridization using DIG-conjugated RNA probes in 1 dpf and 3 dpf embryos. The sense probe (negative or −ve control) gives no staining at 1 dpf or 3 dpf. At 1 dpf, from the lateral view, the anti-sense probe shows ubiquitous staining in the brain, including the forebrain (FB), midbrain-hindbrain boundary (MHB), and the hindbrain; the dorsal view at 1 dpf also revealed staining in fine structures such as the retina and the hypothalamus (inset scale bar 250 μm). Similar brain-specific staining can be observed at 3 dpf for the anti-sense probe, in the forebrain (FB), midbrain (MB) and hindbrain (HB). Staining is also visible in the jaw region at 3 dpf (lateral view, arrow). Scale bars: 1 mm. Domain topology of MTMR5 proteins was mapped using SMART¹⁸ and DeepCoil.¹⁹ Domain illustrations were generated using IBS 2.0.²⁰ Uncropped gels of Fig. 1B are included in Supplementary Fig. 5A.