Clustering and co-localization of immunogold double labelled neural cell adhesion molecule isoforms in chick forebrain.
A quantitative immunoelectron microscopic study was carried out in the intermediate portion of hyperstriatum ventrale of chick forebrain (a region exhibiting learning-related morphological plasticity) in order to examine the fine distribution of the neural cell adhesion molecule (N-CAM). Antibodies against alpha 2,8 polysialic acid (PSA), characteristic for embryonic N-CAM, and those against the protein backbones of all N-CAM isoforms were sequentially labelled (post-embedding) with 5- and 15-nm gold particles, and binding to their epitopes was analyzed using the statistics of point processes. The results showed that: (1) PSA tends to form clusters (up to 200 nm in size), in contrast to the protein backbones of all N-CAM isoforms, and (2) the two tissue bound antibodies are co-localized spatially in clusters of sizes up to 100 nm. The data suggest that there is a spatial sub-cellular domain enriched in both PSA and protein isoforms of N-CAM.
Rusakov
D A
DA
Department of Biology, Open University, Milton Keynes, UK.
Davies
H A
HA
Stewart
M G
MG
Schachner
M
M
D000818:Animals; D000906:Antibodies / Q000276:immunology; D002448:Cell Adhesion / Q000276:immunology*; D002642:Chick Embryo; D006046:Gold; D007150:Immunohistochemistry; D016501:Neurites / Q000276:immunology*; D016548:Prosencephalon / Q000276:immunology / Q000502:physiology*; D012794:Sialic Acids; D013569:Synapses
D000906:Antibodies; D012794:Sialic Acids; D006046:Gold