PUBLICATION
Intestinal dysmotility in a zebrafish (Danio rerio) shank3a;shank3b mutant model of autism
- Authors
- James, D.M., Kozol, R.A., Kajiwara, Y., Wahl, A.L., Storrs, E.C., Buxbaum, J.D., Klein, M., Moshiree, B., Dallman, J.E.
- ID
- ZDB-PUB-190209-15
- Date
- 2019
- Source
- Molecular autism 10: 3 (Journal)
- Registered Authors
- Dallman, Julia, James, David
- Keywords
- Digestive transit, Enteroendocrine, Peristaltic rate, Phelan-McDermid syndrome
- MeSH Terms
-
- Animals
- Autistic Disorder/genetics*
- Autistic Disorder/physiopathology
- Enteric Nervous System/cytology
- Enteric Nervous System/metabolism
- Enteroendocrine Cells/metabolism
- Gastrointestinal Motility*
- Intestinal Mucosa/metabolism
- Intestines/cytology
- Intestines/growth & development
- Intestines/physiology
- Mutation
- Nerve Tissue Proteins/genetics*
- Neurons/metabolism
- Protein Isoforms/genetics
- Protein Isoforms/metabolism
- Serotonin/metabolism
- Zebrafish
- Zebrafish Proteins/genetics*
- PubMed
- 30733854 Full text @ Mol Autism
Citation
James, D.M., Kozol, R.A., Kajiwara, Y., Wahl, A.L., Storrs, E.C., Buxbaum, J.D., Klein, M., Moshiree, B., Dallman, J.E. (2019) Intestinal dysmotility in a zebrafish (Danio rerio) shank3a;shank3b mutant model of autism. Molecular autism. 10:3.
Abstract
Background and aims Autism spectrum disorder (ASD) is currently estimated to affect more than 1% of the world population. For people with ASD, gastrointestinal (GI) distress is a commonly reported but a poorly understood co-occurring symptom. Here, we investigate the physiological basis for GI distress in ASD by studying gut function in a zebrafish model of Phelan-McDermid syndrome (PMS), a condition caused by mutations in the SHANK3 gene.
Methods To generate a zebrafish model of PMS, we used CRISPR/Cas9 to introduce clinically related C-terminal frameshift mutations in shank3a and shank3b zebrafish paralogues (shank3abΔC). Because PMS is caused by SHANK3 haploinsufficiency, we assessed the digestive tract (DT) structure and function in zebrafish shank3abΔC+/- heterozygotes. Human SHANK3 mRNA was then used to rescue DT phenotypes in larval zebrafish.
Results Significantly slower rates of DT peristaltic contractions (p < 0.001) with correspondingly prolonged passage time (p < 0.004) occurred in shank3abΔC+/- mutants. Rescue injections of mRNA encoding the longest human SHANK3 isoform into shank3abΔC+/- mutants produced larvae with intestinal bulb emptying similar to wild type (WT), but still deficits in posterior intestinal motility. Serotonin-positive enteroendocrine cells (EECs) were significantly reduced in both shank3abΔC+/- and shank3abΔC-/- mutants (p < 0.05) while enteric neuron counts and overall structure of the DT epithelium, including goblet cell number, were unaffected in shank3abΔC+/- larvae.
Conclusions Our data and rescue experiments support mutations in SHANK3 as causal for GI transit and motility abnormalities. Reductions in serotonin-positive EECs and serotonin-filled ENS boutons suggest an endocrine/neural component to this dysmotility. This is the first study to date demonstrating DT dysmotility in a zebrafish single gene mutant model of ASD.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping