Molecular cloning and in situ localization of the human contactin gene (CNTN1) on chromosome 12q11-q12.
Chick contactin/F11 (also known as F3 in mouse) is a neuronal cell adhesion molecule of the immunoglobulin (Ig) gene family that is implicated in playing a role in the formation of axon connections in the developing nervous system. In human brain, contactin was first identified by amino terminal and peptide sequencing of the lentil-lectin-binding glycoprotein Gp135. We now report the isolation and characterization of cDNA clones encoding human contactin. Human contactin is composed of six C2 Ig-domains and four fibronectin type III (FNIII) repeats and is anchored to the membrane via a glycosyl phosphatidylinositol moiety, as shown by PI-PLC treatment of cells transfected with contactin cDNA and metabolic labeling with [3H]-ethanolamine. At the amino acid level, h-contactin is 78% identical to chick contactin/F11 and 94% to mouse F3. Independent cDNAs encoding two putative contactin isoforms were isolated and sequenced: h-contactin 1 cDNA encodes a protein with the amino-terminal sequence of purified Gp135, while the putative h-contactin 2 gene has a deletion of 33 nucleotides that predicts a protein with a shortened amino terminus. Northern analysis with a probe common for both isoforms detects one mRNA species of approximately 6.6 kb in adult human brain. Fluorescence in situ hybridization maps the gene for human contactin to human chromosome 12q11-q12. The h-contactin gene locus is thus in close proximity to homeobox 3, integrin subunit alpha 5, several proto-oncogene genes, a chromosomal breakpoint associated with various tumors, and the gene locus for Stickler syndrome. The cloning of human contactin now permits the study of its role in disorders of the human nervous system.
La Jolla Cancer Research Foundation, California 92037.
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Berglund
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Ranscht
D000328:Adult; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D001921:Brain / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000235:genetics; D015816:Cell Adhesion Molecules, Neuronal; D002540:Cerebral Cortex / Q000378:metabolism; D002645:Chickens; D002874:Chromosome Mapping; D002881:Chromosomes, Human, Pair 12; D003001:Cloning, Molecular; D058967:Contactin 1; D058966:Contactins; D017931:DNA Primers; D005801:Genes, Homeobox; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D051379:Mice; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D016133:Polymerase Chain Reaction; D017433:Protein Structure, Secondary; D000090063:Proto-Oncogene Mas; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid
C548669:CNTN1 protein, human; D015815:Cell Adhesion Molecules; D015816:Cell Adhesion Molecules, Neuronal; C548670:Cntn1 protein, mouse; D058967:Contactin 1; D058966:Contactins; D017931:DNA Primers; C000715470:MAS1 protein, human; D009419:Nerve Tissue Proteins; D000090063:Proto-Oncogene Mas; D012333:RNA, Messenger