Human NB-2 of the contactin subgroup molecules: chromosomal localization of the gene (CNTN5) and distinct expression pattern from other subgroup members.
NB-2 is one of the neural recognition molecules in the contactin subgroup, which belongs to the immunoglobulin superfamily. In rat, the six molecules in this subgroup that have been reported to date are contactin, TAG-1, BIG-1, BIG-2, NB-2, and NB-3. We have isolated cDNAs encoding the two splicing isoforms of human NB-2. The long isoform of human NB-2 consists of 1100 amino acids residues that are 91% homologous to rat NB-2 at the amino acid sequence level. The short isoform lacks 74 amino acid residues between residues 19 and 93 of the long isoform. Among various regions of the adult human brain, high-level expression of NB-2 was detected in the amygdala and occipital lobe, whereas expression was low in the corpus callosum, caudate nucleus, and spinal cord. Although there were some differences, the expression pattern of NB-2 was the most similar to that of BIG-1 in the brain. Likewise, contactin and BIG-2 exhibited similar expression patterns. The expression of TAG-1 showed the least regional differences. The human NB-2 gene (CNTN5) was mapped to chromosome 11q21-q22.2 by fluorescence in situ hybridization. Our results suggest that the NB-2 gene may contribute to human neurological disorders.
Kamei
Y
Y
Department of Cell Recognition, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, 173-0015, Japan.
Takeda
Y
Y
Teramoto
K
K
Tsutsumi
O
O
Taketani
Y
Y
Watanabe
K
K
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D015152:Blotting, Northern; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics*; D002871:Chromosome Banding; D002874:Chromosome Mapping; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D058969:Contactin 2; D058966:Contactins; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
C548674:CNTN2 protein, human; C098304:CNTN4 protein, human; D015816:Cell Adhesion Molecules, Neuronal; C548676:Cntn2 protein, rat; C088976:Cntn3 protein, rat; C484360:Cntn4 protein, rat; D058969:Contactin 2; D058966:Contactins; D018076:DNA, Complementary; D008562:Membrane Glycoproteins; D020033:Protein Isoforms; D012333:RNA, Messenger