Molecular characterization and expression pattern of taurine transporter in zebrafish during embryogenesis.
Taurine and its transporter (TauT) are expressed in preimplantation embryos, but their role in embryogenesis is not known. To investigate the role of TauT during embryonic development, we cloned and functionally characterized the zebrafish TauT. The zebrafish TauT cDNA codes for a protein of 625 amino acids which is highly homologous to mammalian TauT. When expressed in mammalian cells, zebrafish TauT mediates taurine uptake in a Na(+)/Cl(-)-dependent manner with a Na(+):Cl(-):taurine stoichiometry of 2:1:1. In the zebrafish embryo, taurine and TauT mRNA are present during early cleavage stages, indicating that both the transporter and its substrate are maternally derived. During embryogenesis, zygotic expression of TauT mRNA is evident in the retina, brain, heart, kidney, and blood vessels. Knockdown of TauT by antisense morpholino oligonucleotides leads to cell death in the central nervous system and increased mortality. These findings suggest a specific role for TauT during development in vertebrates.
Kozlowski
David J
DJ
Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta, GA 30912, USA. dkozlowski@mcg.edu
Chen
Zhong
Z
Zhuang
Lina
L
Fei
You-Jun
YJ
Navarre
Sammy
S
Ganapathy
Vadivel
V
D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D003001:Cloning, Molecular; D047108:Embryonic Development / Q000187:drug effects; D004847:Epithelial Cells / Q000378:metabolism; D006801:Humans; D017403:In Situ Hybridization; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics; D026901:Membrane Transport Proteins / Q000096:biosynthesis* / Q000235:genetics; D008969:Molecular Sequence Data; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D015027:Zebrafish / Q000196:embryology* / Q000378:metabolism; D000099247:Taurine Transporters
D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D016376:Oligonucleotides, Antisense; D000099247:Taurine Transporters