Gne depletion during zebrafish development impairs skeletal muscle structure and function.
GNE Myopathy is a rare recessively inherited neuromuscular disorder caused by mutations in the GNE gene, which codes for the key enzyme in the metabolic pathway of sialic acid synthesis. The process by which GNE mutations lead to myopathy is not well understood. By in situ hybridization and gne promoter-driven fluorescent transgenic fish generation, we have characterized the spatiotemporal expression pattern of the zebrafish gne gene and have shown that it is highly conserved compared with the human ortholog. We also show the deposition of maternal gne mRNA and maternal GNE protein at the earliest embryonic stage, emphasizing the critical role of gne in embryonic development. Injection of morpholino (MO)-modified antisense oligonucleotides specifically designed to knockdown gne, into one-cell embryos lead to a variety of phenotypic severity. Characterization of the gne knockdown morphants showed a significantly reduced locomotor activity as well as distorted muscle integrity, including a reduction in the number of muscle myofibers, even in mild or intermediate phenotype morphants. These findings were further confirmed by electron microscopy studies, where large gaps between sarcolemmas were visualized, although normal sarcomeric structures were maintained. These results demonstrate a critical novel role for gne in embryonic development and particularly in myofiber development, muscle integrity and activity.
Goldyne Savad Institute of Gene Therapy, Hadassah Hebrew University Medical Center, Jerusalem 91240, Israel, School of Marine Sciences, Ruppin Academic Center, Michmoret 40297, Israel.
Alon
A
Daya
Department of Neurobiology, The George S. Wise Faculty of Life Sciences and.
Gad David
GD
Vatine
Goldyne Savad Institute of Gene Therapy, Hadassah Hebrew University Medical Center, Jerusalem 91240, Israel.
Michal
M
Becker-Cohen
Goldyne Savad Institute of Gene Therapy, Hadassah Hebrew University Medical Center, Jerusalem 91240, Israel.
Tzukit
T
Tal-Goldberg
School of Marine Sciences, Ruppin Academic Center, Michmoret 40297, Israel.
Adam
A
Friedmann
Department of Neurobiology, The George S. Wise Faculty of Life Sciences and Sagol School of Neuroscience, Tel-Aviv University, Tel Aviv 69978, Israel.
Yoav
Y
Gothilf
Institute of Marine and Environmental Technology, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
Shao Jun
SJ
Du
Goldyne Savad Institute of Gene Therapy, Hadassah Hebrew University Medical Center, Jerusalem 91240, Israel, stella@mail.huji.ac.il.
Stella
S
Mitrani-Rosenbaum
D000818:Animals; D006801:Humans; D008854:Microscopy, Electron; D009097:Multienzyme Complexes / Q000235:genetics / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism*; D009154:Mutation; D016376:Oligonucleotides, Antisense / Q000235:genetics; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism*
D009097:Multienzyme Complexes; D016376:Oligonucleotides, Antisense; C482901:UDP-N-acetylglucosamine 2-epimerase - N-acetylmannosamine kinase; D029961:Zebrafish Proteins