Behavioral and Sensory Deficits Associated with Dysfunction of GABAergic System in a Novel shank2-Deficient Zebrafish...

Area of Science:

• Neuroscience
• Genetics
• Developmental Biology

Background:

• Sensory hyper-reactivity is a common, debilitating autism spectrum disorder (ASD) symptom.
• Underlying neural abnormalities in ASD sensory processing remain unclear.
• De novo SHANK2 mutations are found in some individuals with ASD and sensory sensitivities.

Purpose of the Study:

• To investigate if SHANK2 deficiency contributes to sensory abnormalities and ASD-like phenotypes.
• To generate and characterize a zebrafish model with shank2b deficiency.

Main Methods:

• Generated a stable shank2b-deficient zebrafish model.
• Assessed social behavior, stereotypy, and sensory responses (auditory, visual, tactile) in adult and larval zebrafish.
• Analyzed expression of GABA receptor subunits.
• Tested sensitivity to drug-induced seizures.

Main Results:

• Shank2b-deficient zebrafish exhibited reduced social and kin preference, and increased stereotypy.
• Larval shank2b zebrafish showed auditory hyper-sensitivity and hyperactivity.
• Reduced expression of GABA receptor subunits and increased seizure sensitivity were observed.
• The model recapitulated core developmental and behavioral phenotypes of genetic ASD models.

Conclusions:

• SHANK2 deficiency contributes to sensory hyper-reactivity and other ASD-like behaviors.
• GABAergic dysfunction is a key factor in ASD-related sensory processing disruptions.
• Early interventions targeting sensory processing may prevent disease progression in ASD.