Other Publications (1)
Articles by Devon L. Johnstone in JoVE
High-throughput DNA Extraction and Genotyping of 3dpf Zebrafish Larvae by Fin Clipping Ceres Kosuta1,2, Kate Daniel1, Devon L. Johnstone1,2, Kevin Mongeon1,2, Kevin Ban1,2, Sophie LeBlanc1, Stuart MacLeod1, Karim Et-Tahiry2, Marc Ekker2, Alex MacKenzie1, Izabella Pena1,2 1 Zebrafish have been used as reliable genetic model organisms in biomedical research, especially with the advent of gene-editing technologies. When larval phenotypes are expected, DNA extraction and genotype identification can be challenging. Here, we describe an efficient genotyping procedure for zebrafish larvae, by tail clipping, as early as 72-h post-fertilization.
Other articles by Devon L. Johnstone on PubMed
Compound Heterozygous Mutations in the Gene PIGP Are Associated with Early Infantile Epileptic Encephalopathy Human Molecular Genetics. 05, 2017 | Pubmed ID: 28334793 There are over 150 known human proteins which are tethered to the cell surface via glycosylphosphatidylinositol (GPI) anchors. These proteins play a variety of important roles in development, and particularly in neurogenesis. Not surprisingly, mutations in the GPI anchor biosynthesis and remodeling pathway cause a number of developmental disorders. This group of conditions has been termed inherited GPI deficiencies (IGDs), a subgroup of congenital disorders of glycosylation; they present with variable phenotypes, often including seizures, hypotonia and intellectual disability. Here, we report two siblings with compound heterozygous variants in the gene phosphatidylinositol glycan anchor biosynthesis, class P (PIGP) (NM_153681.2: c.74T > C;p.Met25Thr and c.456delA;p.Glu153AsnFs*34). PIGP encodes a subunit of the enzyme that catalyzes the first step of GPI anchor biosynthesis. Both children presented with early-onset refractory seizures, hypotonia, and profound global developmental delay, reminiscent of other IGD phenotypes. Functional studies with patient cells showed reduced PIGP mRNA levels, and an associated reduction of GPI-anchored cell surface proteins, which was rescued by exogenous expression of wild-type PIGP. This work associates mutations in the PIGP gene with a novel autosomal recessive IGD, and expands our knowledge of the role of PIG genes in human development.