Fig. 1: RNF121^M158R mutation blocks neuroblastoma development in TH-MYCN mice.

a Homozygous TH-MYCN (TH-MYCN^+/+) mice were screened for delay in tumour development after ENU chemical treatment. Homozygous TH-MYCN (TH-MYCN^+/+) breeder mice were treated for 2 weeks with cyclophosphamide to prevent tumour progression, then subjected to N-ethyl-N-nitrosourea (ENU) chemical mutagenesis of their germline at 6 weeks of age to induce random mutations in their sperm genome. b Tumour latency in 13 offspring of mouse 1929. Approximately half of the progeny developed tumours by the expected 7 weeks postnatal, whereas the remainder exhibited increased tumour latency. A subset of these mice did not develop tumours. Parent mouse 1929, that did not develop a tumour, is shown as a comparison. c, d Mouse 1929 or non-ENU-treated TH-MYCN^+/+ mice were crossed with BALB/c (c) and C57BL/6 (d) wild-type mice before backcrossing with Cyclophosphamide-treated TH-MYCN^+/+ mice. The mice represented by red triangles were selected for exome sequencing. e An RNF121^M158R mutation was identified by exome sequencing of tumours from all 14 offspring with the tumour-suppressed phenotype. f A 3D model of RNF121^M158R showing the location of the mutation. The secondary structures with the light and darker blue colours are predicted with the most confidence, whereas the yellow and red colours signify the least confident predictions. The yellow horizontal bars signify the approximate locations of the membrane surfaces. A zoomed in view of the Met 158 microenvironment is shown in the box. Met 158, located in transmembrane helix 4, and surrounding residues are shown in ball-and-stick format.