Sinuous is a Drosophila claudin required for septate junction organization and epithelial tube size control.
Epithelial tubes of the correct size and shape are vital for the function of the lungs, kidneys, and vascular system, yet little is known about epithelial tube size regulation. Mutations in the Drosophila gene sinuous have previously been shown to cause tracheal tubes to be elongated and have diameter increases. Our genetic analysis using a sinuous null mutation suggests that sinuous functions in the same pathway as the septate junction genes neurexin and scribble, but that nervana 2, convoluted, varicose, and cystic have functions not shared by sinuous. Our molecular analyses reveal that sinuous encodes a claudin that localizes to septate junctions and is required for septate junction organization and paracellular barrier function. These results provide important evidence that the paracellular barriers formed by arthropod septate junctions and vertebrate tight junctions have a common molecular basis despite their otherwise different molecular compositions, morphologies, and subcellular localizations.
Wu
Victoria M
VM
Department of Biochemistry, Molecular Biology, and Cell Biology, Northwestern University, Hogan Hall, Rm. 2-100, Northwestern University, 2205 Tech Drive, Evanston, IL 60208-3500, USA.
Schulte
Joost
J
Hirschi
Alexander
A
Tepass
Ulrich
U
Beitel
Greg J
GJ
D000818:Animals; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000502:physiology* / Q000648:ultrastructure; D004847:Epithelial Cells / Q000166:cytology* / Q000648:ultrastructure; D007365:Intercellular Junctions / Q000502:physiology* / Q000648:ultrastructure; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011487:Protein Conformation
D029721:Drosophila Proteins; D008565:Membrane Proteins; C489410:sinu protein, Drosophila