ZFIN ID: ZDB-PUB-131115-9
Analysis of three mu-AP1 subunits during zebrafish development
Gariano, G., Guarienti, M., Bresciani, R., Borsani, G., Carola, G., Monti, E., Giuliani, R., Rezzani, R., Bonomini, F., Preti, A., Schu, P., and Zizioli, D.
Date: 2014
Source: Developmental dynamics : an official publication of the American Association of Anatomists   243(2): 299-314 (Journal)
Registered Authors: Borsani, Giuseppe
Keywords: adaptin, central nervous system, development, kidney, vesicular transport, zebrafish
MeSH Terms:
  • Acridine Orange
  • Adaptor Protein Complex 1/genetics
  • Adaptor Protein Complex 1/metabolism
  • Adaptor Protein Complex beta Subunits/genetics
  • Adaptor Protein Complex beta Subunits/metabolism
  • Adaptor Protein Complex mu Subunits/genetics
  • Adaptor Protein Complex mu Subunits/metabolism*
  • Animals
  • Base Sequence
  • DNA Primers/genetics
  • Embryonic Development/genetics*
  • Gene Knockdown Techniques
  • In Situ Hybridization
  • Molecular Sequence Data
  • Morpholinos/genetics
  • Phylogeny
  • Protein Subunits/genetics
  • Protein Transport/genetics
  • Protein Transport/physiology
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Alignment
  • Sequence Analysis
  • Zebrafish/embryology*
  • Zebrafish/metabolism
  • trans-Golgi Network/metabolism*
PubMed: 24123392 Full text @ Dev. Dyn.

Background: The family of AP-1 complexes mediates protein sorting in the late secretory pathway and it is essential for the development of mammals. The ubiquitously expressed AP-1A complex consists of four adaptins γ1, β1, μ1A and σ1A. AP-1A mediates protein transport between the trans-Golgi network and early endosomes The polarized epithelia AP-1B complex contains the μ1B-adaptin. AP-1B mediates specific transport of proteins from basolateral recycling endosomes to the basolateral plasma membrane of polarized epithelial cells. Results: Analysis of the zebrafish genome revealed the existence of three 1-adaptin genes, encoding 1A, 1B and the novel isoform μ1C, which is not found in mammals. μ1C shows 80% sequence identity with 1A and 1B. The 1C expression pattern largely overlaps with that of 1A, while 1B is expressed in epithelial cells. By knocking-down the synthesis of 1A, 1B and 1C with antisense morpholino techniques we demonstrate that each of these 1 adaptins is essential for zebrafish development, with 1A and 1C being involved in central nervous system development and 1B in kidney formation. Conclusions: Zebrafish is unique in expressing three AP-1 complexes: AP-1A, AP-1B and AP-1C. Our results demonstrate that they are not redundant and that each of them has specific functions, which can not be fulfilled by one of the other isoforms. Each of the 1 adaptins appears to mediate specific molecular mechanisms essential for early developmental processes, which depend on specific intracellular vesicular protein sorting pathways.