Focusing forward genetics: a tripartite ENU screen for neurodevelopmental mutations in the mouse

Genetics. 2011 Jul;188(3):615-24. doi: 10.1534/genetics.111.126862. Epub 2011 Apr 21.

Abstract

The control of growth, patterning, and differentiation of the mammalian forebrain has a large genetic component, and many human disease loci associated with cortical malformations have been identified. To further understand the genes involved in controlling neural development, we have performed a forward genetic screen in the mouse (Mus musculus) using ENU mutagenesis. We report the results from our ENU screen in which we biased our ascertainment toward mutations affecting neurodevelopment. Our screen had three components: a careful morphological and histological examination of forebrain structure, the inclusion of a retinoic acid response element-lacZ reporter transgene to highlight patterning of the brain, and the use of a genetically sensitizing locus, Lis1/Pafah1b1, to predispose animals to neurodevelopmental defects. We recovered and mapped eight monogenic mutations, seven of which affect neurodevelopment. We have evidence for a causal gene in four of the eight mutations. We describe in detail two of these: a mutation in the planar cell polarity gene scribbled homolog (Drosophila) (Scrib) and a mutation in caspase-3 (Casp3). We find that refining ENU mutagenesis in these ways is an efficient experimental approach and that investigation of the developing mammalian nervous system using forward genetic experiments is highly productive.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • 1-Alkyl-2-acetylglycerophosphocholine Esterase / genetics
  • 1-Alkyl-2-acetylglycerophosphocholine Esterase / metabolism
  • Animals
  • Caspase 3 / genetics
  • Caspase 3 / metabolism
  • Chromosome Mapping
  • Crosses, Genetic
  • DNA Fingerprinting
  • Ethylnitrosourea / administration & dosage
  • Ethylnitrosourea / adverse effects*
  • Female
  • Gene Expression Regulation, Developmental*
  • Genes, Reporter
  • Genetic Association Studies*
  • Heterozygote
  • High-Throughput Screening Assays*
  • Homozygote
  • Humans
  • Immunohistochemistry
  • Intracellular Signaling Peptides and Proteins / genetics
  • Intracellular Signaling Peptides and Proteins / metabolism
  • Male
  • Mice
  • Microtubule-Associated Proteins / genetics
  • Microtubule-Associated Proteins / metabolism
  • Mutagens / administration & dosage
  • Mutagens / adverse effects*
  • Mutation
  • Nervous System Diseases / embryology
  • Nervous System Diseases / genetics*
  • Nervous System Diseases / metabolism
  • Nervous System Diseases / pathology
  • Phenotype
  • Polymorphism, Single Nucleotide
  • Prosencephalon / cytology
  • Prosencephalon / drug effects
  • Prosencephalon / embryology
  • Prosencephalon / metabolism*
  • Transgenes

Substances

  • Intracellular Signaling Peptides and Proteins
  • Microtubule-Associated Proteins
  • Mutagens
  • scribble protein, mouse
  • 1-Alkyl-2-acetylglycerophosphocholine Esterase
  • Pafah1b1 protein, mouse
  • Casp3 protein, mouse
  • Caspase 3
  • Ethylnitrosourea