Mouse ten-m/Odz is a new family of dimeric type II transmembrane proteins expressed in many tissues.
The Drosophila gene ten-m/odz is the only pair rule gene identified to date which is not a transcription factor. In an attempt to analyze the structure and the function of ten-m/odz in mouse, we isolated four murine ten-m cDNAs which code for proteins of 2,700-2, 800 amino acids. All four proteins (Ten-m1-4) lack signal peptides at the NH2 terminus, but contain a short hydrophobic domain characteristic of transmembrane proteins, 300-400 amino acids after the NH2 terminus. About 200 amino acids COOH-terminal to this hydrophobic region are eight consecutive EGF-like domains. Cell transfection, biochemical, and electronmicroscopic studies suggest that Ten-m1 is a dimeric type II transmembrane protein. Expression of fusion proteins composed of the NH2-terminal and hydrophobic domain of ten-m1 attached to the alkaline phosphatase reporter gene resulted in membrane-associated staining of the alkaline phosphatase. Electronmicroscopic and electrophoretic analysis of a secreted form of the extracellular domain of Ten-m1 showed that Ten-m1 is a disulfide-linked dimer and that the dimerization is mediated by EGF-like modules 2 and 5 which contain an odd number of cysteines. Northern blot and immunohistochemical analyses revealed widespread expression of mouse ten-m genes, with most prominent expression in brain. All four ten-m genes can be expressed in variously spliced mRNA isoforms. The extracellular domain of Ten-m1 fused to an alkaline phosphatase reporter bound to specific regions in many tissues which were partially overlapping with the Ten-m1 immunostaining. Far Western assays and electronmicroscopy demonstrated that Ten-m1 can bind to itself.
Oohashi
T
T
Max Planck Institute for Biochemistry, 82152 Martinsried, Germany.
Zhou
X H
XH
Feng
K
K
Richter
B
B
Mörgelin
M
M
Perez
M T
MT
Su
W D
WD
Chiquet-Ehrismann
R
R
Rauch
U
U
Fässler
R
R
D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D001923:Brain Chemistry; D002462:Cell Membrane / Q000737:chemistry / Q000201:enzymology; D018076:DNA, Complementary; D019281:Dimerization; D029721:Drosophila Proteins; D016228:Endothelial Growth Factors / Q000737:chemistry / Q000235:genetics; D015870:Gene Expression / Q000502:physiology; D008565:Membrane Proteins; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000502:physiology*; D009419:Nerve Tissue Proteins; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000032:analysis; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D019063:Tenascin / Q000032:analysis / Q000737:chemistry / Q000235:genetics*
D018076:DNA, Complementary; D029721:Drosophila Proteins; D016228:Endothelial Growth Factors; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; C089140:Ten-m protein, Drosophila; D019063:Tenascin; C120530:teneurin-1; D000469:Alkaline Phosphatase