title: Transient association of the HNK-1 epitope with 5'-nucleotidase during development of the cat visual cortex.
abstract: During early postnatal development of the kitten visual cortex the ectoenzyme 5'-nucleotidase undergoes a characteristic redistribution. Until about postnatal week 6 it is essentially confined to synaptic contacts in input layer IV and its expression is related to the use-dependent segregation of thalamic afferents into ocular dominance columns. Subsequently, 5'-nucleotidase becomes distributed uniformly throughout all layers and is then associated selectively with glial cells. Here we describe an age-dependent alteration in the expression of a carbohydrate epitope of 5'-nucleotidase which correlates with the developmental change of the enzyme's localization. We have isolated 5'-nucleotidase from the occipital cortex of kittens of varying age and from adult cats and investigated by immunoblotting the association of the HNK-1 carbohydrate epitope with the protein. 5'-Nucleotidase carries the HNK-1 epitope in kittens of 3-9 weeks but the epitope is absent from 12-week-old kittens or adult cats. Thus, the appearance of the HNK-1 epitope correlates with the transient localization of the enzyme at synapses. The HNK-1 carrying 5'-nucleotidase may be involved in synaptogenesis and use-dependent modifications of synaptic connections.
authors.affiliation: Zoologisches Institut, J.W. Goethe-Universität, Frankfurt am Main, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Vogel
authors.forename: H
authors.initials: H
authors.lastname: Zimmermann
authors.forename: W
authors.initials: W
authors.lastname: Singer
mesh_terms: D015720:5'-Nucleotidase / Q000032:analysis / Q000378:metabolism*; D000375:Aging / Q000378:metabolism*; D000818:Animals; D015703:Antigens, CD / Q000032:analysis / Q000378:metabolism*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis / Q000378:metabolism*; D018959:CD57 Antigens; D002415:Cats; D000939:Epitopes / Q000032:analysis; D013569:Synapses / Q000378:metabolism; D014793:Visual Cortex / Q000254:growth & development / Q000378:metabolism*
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D018959:CD57 Antigens; D000939:Epitopes; D015720:5'-Nucleotidase