PUBLICATION

Myofibrillogenesis in the Developing Zebrafish Heart: A Functional Study of tnnt2

Authors
Huang, W., Zhang, R., and Xu, X.
ID
ZDB-PUB-090518-1
Date
2009
Source
Developmental Biology   331(2): 237-249 (Journal)
Registered Authors
Huang, Wei, Xu, Xiaolei, Zhang, Ruilin
Keywords
Myofibrillogenesis, sarcomere, zebrafish, heart, tnnt2
MeSH Terms
  • Sarcomeres/physiology
  • Troponin T/physiology*
  • Myosins/physiology
  • Myofibrils/physiology*
  • Zebrafish/embryology
  • Zebrafish/physiology*
  • Myocytes, Cardiac/cytology
  • Myocytes, Cardiac/physiology*
  • Animals
  • Heart/embryology*
  • Myocardium/metabolism
  • Zebrafish Proteins/physiology*
  • Actin Cytoskeleton/physiology
  • Models, Animal
(all 14)
PubMed
19427304 Full text @ Dev. Biol.
Abstract
Various hypotheses have been proposed to explain the molecule processes of sarcomere assembly, partially due to the lack of systematic genetic studies of sarcomeric genes in an in vivo model. Towards the goal of developing zebrafish as a vertebrate model for this purpose, we characterized myofibrillogenesis in a developing zebrafish heart and went on to examine the functions of cardiac troponin T (tnnt2). We found that sarcomere assembly in zebrafish heart was initiated from a non-striated actin filament network at the perimembrane region, whereas sarcomeric myosin is independently assembled into thick filaments of variable length before integrating into the thin filament network. Compared to Z-discs that are initially aligned to form shorter periodic dots and expanded longitudinally at a later time, M-lines assemble later and have a constant length. Depletion of full-length tnnt2 disrupted the striation of thin filaments and Z-bodies, which sequentially affects the striation of thick filaments and M-lines. Conversely, truncation of a C-terminal troponin complex-binding domain did not affect the striation of these sarcomere sub-structures, but resulted in reduced cardiomyocyte size. In summary, our data indicates that zebrafish are a valuable in vivo model for studying both myofibrillogenesis and sarcomere-based cardiac diseases.
Genes / Markers
Figures
Figure Gallery (10 images)
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Expression
No data available
Phenotype
No data available
Mutations / Transgenics
Allele Construct Type Affected Genomic Region
b109
    Small Deletion
    1 - 1 of 1
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    Human Disease / Model
    No data available
    Sequence Targeting Reagents
    Target Reagent Reagent Type
    tnnt2aMO1-tnnt2aMRPHLNO
    tnnt2aMO2-tnnt2aMRPHLNO
    1 - 2 of 2
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    Fish
    1 - 1 of 1
    Show
    Antibodies
    Orthology
    No data available
    Engineered Foreign Genes
    No data available
    Mapping
    No data available