ZFIN ID: ZDB-PUB-100126-1
Disruption of zebrafish cyclin G-associated kinase (GAK) function impairs the expression of Notch-dependent genes during neurogenesis and causes defects in neuronal development
Bai, T., Seebald, J.L., Kim, K.E., Ding, H.M., Szeto, D.P., and Chang, H.C.
Date: 2010
Source: BMC Developmental Biology 10: 7 (Journal)
Registered Authors: Szeto, Daniel P.
Keywords: none
MeSH Terms:
  • Amino Acid Sequence
  • Animals
  • Auxilins/genetics
  • Brain/embryology
  • Brain/metabolism
  • Cell Death
  • Clathrin/metabolism
  • Gene Expression
  • Homeodomain Proteins/metabolism
  • Humans
  • Molecular Sequence Data
  • Neurogenesis*
  • Protein-Serine-Threonine Kinases/metabolism*
  • Zebrafish/embryology*
  • Zebrafish/metabolism
  • Zebrafish Proteins/metabolism*
PubMed: 20082716 Full text @ BMC Dev. Biol.
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ABSTRACT
BACKGROUND: The J-domain-containing protein auxilin, a critical regulator in clathrin-mediated transport, has been implicated in Drosophila Notch signaling. To ask if this role of auxilin is conserved and whether auxilin has additional roles in development, we have investigated the functions of auxilin orthologs in zebrafish. RESULTS: Like mammals, zebrafish has two distinct auxilin-like molecules, auxilin and cyclin G-associated kinase (GAK), differing in their domain structures and expression patterns. Both zebrafish auxilin and GAK can functionally substitute for the Drosophila auxilin, suggesting that they have overlapping molecular functions. Still, they are not completely redundant, as morpholino-mediated knockdown of the ubiquitously expressed GAK alone can increase the specification of neuronal cells, a known Notch-dependent process, and decrease the expression of Her4, a Notch target gene. Furthermore, inhibition of GAK function caused an elevated level of apoptosis in neural tissues, resulting in severe degeneration of neural structures. CONCLUSION: In support of the notion that endocytosis plays important roles in Notch signaling, inhibition of zebrafish GAK function affects embryonic neuronal cell specification and Her4 expression. In addition, our analysis suggests that zebrafish GAK has at least two functions during the development of neural tissues: an early Notch-dependent role in neuronal patterning and a late role in maintaining the survival of neural cells.
ADDITIONAL INFORMATIONNo data available