nbea mutant zebrafish responded to a 500 Hz, 10 msec tone with escape responses less than half as frequently as their wildtype controls. nbea mutant animals showed a balance defect exhibited by frequently lying on their sides although swim bladder development was normal. nbea mutant animals were less sensitive to touch, displayed decreased overall motion, and were generally less reactive than their wildtype counterparts.
References
Type
Title
Author, Year
Primary
Neurobeachin is required postsynaptically for electrical and chemical synapse formation.
Model Type:
Genetic
Model Genotype:
Homozygous
Mutation:
An ethylnitrosourea induced zebrafish mutant, called Disconnect4 (dis4), that was mapped to have 1 nonsense mutation in the neurobeachin gene that truncates the gene product at amino acid 906 along with 11 missense mutations in other genes. The nonsense mutation in nbea was demonstrated to be the mutation responsible for the dis4 phenotype as zebrafish with a 7 base pair (bp) frameshifting deletion in the first exon (nbea-fh392) and an 8 bp frameshifting deletion in exon 21 (nbea-fh380), generated using TALEN, failed to complement the dis4 ENU generated mutant phenotype. Based on mapping studies dis4 was renamed nbea-fh364. nbea-fh364 zebrafish has a C to T transition in exon 21 introducing a nonsense codon that truncates the protein approximately one third of the way through the protein. Et(Tol-056:GFP) transgenic line which expresses GFP in Mauthner and Commissural Local neurons was used to identify these neuron types. The genotype of the fish is: nbea^fh364/fh364; zf206Et (AB/TU).
Allele Type: Targeted (knockout)
Strain of Origin: Genetic Background: ES Cell Line: Mutant ES Cell Line: Model Source: Walker C, 2009 (PMID:19568220)
Model Type:
Genetic
Model Genotype:
Heterozygous
Mutation:
An ethylnitrosourea induced zebrafish mutant, called Disconnect4 (dis4), that was mapped to have 1 nonsense mutation in the neurobeachin gene that truncates the gene product at amino acid 906 along with 11 missense mutations in other genes. The genotype of the fish is: nbeaa^fh364/+; zf206Et (AB/TU).
Allele Type: Targeted (knockout)
Strain of Origin: Genetic Background: ES Cell Line: Mutant ES Cell Line: Model Source: Walker C, 2009 (PMID:19568220)
Model Type:
Genetic
Model Genotype:
Other
Mutation:
Zebrafish with transplanted cells from an nbea mutant, Et(Tol-056:GFP) transgenic donor (which expresses GFP in Mauthner and Commissural Local neurons) into a wildtype host embryo at the blastula stage and adult animals with nbea mutant Mauthner neurons were studied.
Allele Type: Mosaic
Strain of Origin: Genetic Background: ES Cell Line: Mutant ES Cell Line: Model Source: Walker C, 2009 (PMID:19568220)
Model Type:
Genetic
Model Genotype:
Other
Mutation:
Zebrafish with transplanted cells from an nbea mutant, Et(Tol-056:GFP) transgenic donor (which expresses GFP in Mauthner and Commissural Local neurons) into a wildtype host embryo at the blastula stage. Adult animals with nbea mutant post-synaptic commissural local neurons were studied.
Allele Type: Mosaic
Strain of Origin: Genetic Background: ES Cell Line: Mutant ES Cell Line: Model Source: Walker C, 2009 (PMID:19568220)
Model Type:
Genetic
Model Genotype:
Other
Mutation:
Zebrafish with transplanted cells from an nbea mutant, Et(Tol-056:GFP) transgenic donor (which expresses GFP in Mauthner and Commissural Local neurons) into a wildtype host embryo at the blastula stage and adult animals with nbea mutant post-synaptic Commissural local neurons and mutant pre synaptic Mauthner neurons were studied.
Allele Type: Mosaic
Strain of Origin: Genetic Background: ES Cell Line: Mutant ES Cell Line: Model Source: Walker C, 2009 (PMID:19568220)
Model Type:
Genetic
Model Genotype:
Other
Mutation:
Zebrafish with transplanted cells from an nbea mutant, Et(Tol-056:GFP) transgenic donor (which expresses GFP in Mauthner and Commissural Local neurons) into a wildtype host embryo at the blastula stage and adult animals with nbea mutant pre-synaptic Commissural local neurons were studied.
Allele Type: Mosaic
Strain of Origin: Genetic Background: ES Cell Line: Mutant ES Cell Line: Model Source: Walker C, 2009 (PMID:19568220)
Model Type:
RESCUE-Transplantation
Model Genotype:
Other
Mutation:
Zebrafish with transplanted cells from wildtype, M/CoLo:GFP embryos were transplanted into unmarked, nbea mutant hosts. Adult fish with wildtype commissural local neurons were used in the study.
Allele Type: Mosaic
Strain of Origin: Genetic Background: ES Cell Line: Mutant ES Cell Line: Model Source: Walker C, 2009 (PMID:19568220)
Model Type:
RESCUE-Transplantation
Model Genotype:
Other
Mutation:
Zebrafish with transplanted cells from wildtype, M/CoLo:GFP embryos were transplanted into unmarked, nbea mutant hosts. Adult fish with wildtype Mauthner neurons were used in the study.
Allele Type: Mosaic
Strain of Origin: Genetic Background: ES Cell Line: Mutant ES Cell Line: Model Source: Walker C, 2009 (PMID:19568220)
Model Type:
RESCUE-Transplantation
Model Genotype:
Other
Mutation:
Zebrafish with transplanted cells from wildtype, M/CoLo:GFP embryos were transplanted into unmarked, nbea mutant hosts. Adult fish with wildtype postsynaptic neurons on Mauthner neurons or Commissural Local neurons were used in the study.
Allele Type: Mosaic
Strain of Origin: Genetic Background: ES Cell Line: Mutant ES Cell Line: Model Source: Walker C, 2009 (PMID:19568220)
Model Type:
RESCUE-Transplantation
Model Genotype:
Other
Mutation:
Zebrafish with transplanted cells from wildtype, M/CoLo:GFP embryos were transplanted into unmarked, nbea mutant hosts. Adult fish with wildtype presynatptic neurons on Mauthner neurons and Commissural Local neurons were used in the study.
Allele Type: Mosaic
Strain of Origin: Genetic Background: ES Cell Line: Mutant ES Cell Line: Model Source: Walker C, 2009 (PMID:19568220)
Description: nbea mutant shows decreased expression of connexin36, a marker of electrical synapses, at sensory/Mauthner neurons and Mauthner/Commissural local neuron synapses, compared to controls. nbea mutants show decreased connexin36 staining in the M circuit, (3-14 dpf) and also at electrical synapses in the forebrain, midbrain, hindbrain and spinal cord compared to controls.
Description: nbea mutant shows decreased expression of the cytosolic scaffold protein ZO-1, found at electrical synapses and non-synaptic tight junctons, compared to controls. ZO-1 colocalized with Cx36 and within the M circuit.
Description: nbea mutant shows decreased expression of the cytosolic scaffold protein Gephyrin, found at glycinergic inhibitory synapses, compared to controls.
Dendritic architecture: dendritic tree complexity1
Decreased
Description: nbea mutant shows decreased dendritic tree complexity of Mauthner neurons compared to controls. Time course analysis shows nbea is required to maintain the extensive branching and fine dendritic processes found in mature neurons.
Description: nbea mutant shows decreased expression of glycine receptor at Mauther neuron synapses in the hindbrain and spinal cord, compared to controls. Ablation of M circuit led to a loss of GlyR associated with M dendrites in the hindbrain but did not affect GlyR in the CoLo/CoLo synapses in the spinal cord. At CoLo/CoLo synapses in nbea mutants GlyR was reduced, compared to controls.
Description: nbea mutants show decreased frequency of response in acoustic startle reponse test compared to wildtype controls although mutants could perform escape responses that were indistinguishable from wildtype but responded in fewer trials.
Description: When the Mauthner cell is nbea mutant in a wildtype animal the GlyR staining on its postsynaptic dendrites in the hindbrain is reduced compared to controls.
Description: When Mauthner cell is nbea mutant in a wildtype host it loses its sensory input electrical synapses in the hindbrain compared to controls.
Description: When the postsynaptic commissural local neuron or the presynaptic M neuron or both were nbea mutant connexin36 labeling decreased compared to wildtype controls. When Mauthner cell is nbea mutant in a wildtype host it loses its sensory input synapses in the hindbrain.
Description: At the Comissural Local /Commissural Local neuronal synapses removing nbea from the postsynaptic neuron decreases GlyR fluorescence compared to controls.
Description: When the postsynaptic commissural local neuron and the presynaptic M neuron were nbea mutant connexin36 labeling decreased compared to wildtype controls.
Description: At the Comissural Local /Commissural Local neuronal synapses removing nbea from the pre and postsynaptic neuron decreases GlyR fluorescence compared to controls but there is no additive affect.
Description: When the postsynaptic Commissural Local neuron was wildtype in a mutant host the Mauthner-Commissural Local synapse was rescued with increase in Connexin36 fluorescence compared to the mutant synapses within the same animals. When the presynaptic M axon was wildtype in a nbea mutant background there was no rescue of connexin36.
Description: When Mauthner cell is wildtype in an nbea mutant animal the Connexin36 associated with electrical synapses on its postsynaptic dendrites and cell body in the hindbrain are rescued compared to nbea mutant animals.
Description: When the postsynaptic neuron in M cells or Commissural Local neurons was wildtype in a nbea mutant background Glycine receptor expression was rescued compared to nbea mutant animals.
Description: When the presynaptic M axon was wildtype in a nbea mutant background there was no rescue of connexin36 compared to the mutant synapses within the same animals. Nbeas postsynaptic rescue of Connexin36 at the synapse is not enhanced when the presynaptic neuron is wildtype.
Description: When the presynaptic M axon was wildtype in a nbea mutant background Glycine receptor expression was rescued not compared to nbea mutant animals.
