The contactin-related protein FAR-2 defines purkinje cell clusters and labels subpopulations of climbing fibers in the developing cerebellum.
FAR-2 is a novel neural member of the Ig superfamily, which is related to F11/F3/contactin and axonin-1/TAG-1. This protein is expressed by subpopulations of Purkinje cells in the chicken cerebellum and FAR-2-positive clusters of these neurons alternate with FAR-2-negative clusters in both tangential dimensions of the cerebellar cortex. Furthermore, FAR-2 is also expressed by one type of Purkinje cell afferents, namely, the climbing fibers, and different subpopulations of these axons show distinct levels of FAR-2 expression. Homology modeling using axonin-1 as a template reveals that the four aminoterminal Ig domains of FAR-2 form a compact U-shaped structure, which is likely to contain functionally important ligand-binding sites. FAR-2 is binding to the Ig superfamily protein NgCAM/L1, but not to the related receptor NrCAM, and it is also interacting with the modular ECM protein tenascin-R. These results suggest that FAR-2 may contribute to the formation of somatotopic maps of cerebellar afferents during the development of the nervous system.
Plagge
A
A
Max-Planck-Institute for Developmental Biology, Tübingen, Germany.
Sendtner-Voelderndorff
L
L
Sirim
P
P
Freigang
J
J
Rader
C
C
Sonderegger
P
P
Brümmendorf
T
T
D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D015816:Cell Adhesion Molecules, Neuronal / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D002465:Cell Movement / Q000502:physiology; D002531:Cerebellum / Q000166:cytology* / Q000196:embryology* / Q000502:physiology; D002642:Chick Embryo; D002645:Chickens; D058969:Contactin 2; D058966:Contactins; D005109:Extracellular Matrix / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D039841:Leukocyte L1 Antigen Complex; D008024:Ligands; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D019006:Neural Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism; D016501:Neurites / Q000502:physiology; D017434:Protein Structure, Tertiary; D011689:Purkinje Cells / Q000166:cytology* / Q000502:physiology*; D019063:Tenascin / Q000378:metabolism; D014162:Transfection
D015816:Cell Adhesion Molecules, Neuronal; D058969:Contactin 2; D058966:Contactins; C435269:FAR-2 protein, chicken; D039841:Leukocyte L1 Antigen Complex; D008024:Ligands; D008562:Membrane Glycoproteins; D019006:Neural Cell Adhesion Molecules; D019063:Tenascin; C074638:tenascin R