Transport of cytoskeletal proteins in axons of hippocampal pyramidal cells.
Axonal transport of cytoskeletal proteins has not yet been extensively studied in the brain proper, in contrast to the peripheral nerves and optic nerves. The authors have developed a means for the study of transport of cytoskeletal proteins in axons of hippocampal pyramidal cells. Proteins of intrinsic neurons of the dorsal hippocampus were labeled by microinjection of 35S methionine, and the subsequent transport of labeled proteins was characterized in the axons projecting into the fimbria-fornix. A peak of labeled proteins was present in the fimbria-fornix at 4-12 days after labeling, corresponding to transport rates 0.2-0.7 mm/day. The most abundant proteins at each time studied exhibited one-dimensional electrophoretic mobilities of actin and tubulin; neurofilaments were less intensely labeled. The observed specializations of cytoskeletal transport, especially the paucity of tubulin transport at rates of 2-4 mm/day, may predispose hippocampal pyramidal cells to accumulate tubulin and microtubule-associated proteins in their cell bodies in various disease states.
Watson
D F
DF
Department of Neurology, Wayne State University School of Medicine, Detroit, MI 48201.
Fittro
K P
KP
D000199:Actins / Q000378:metabolism; D000818:Animals; D001370:Axonal Transport; D001369:Axons / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism*; D008297:Male; D008715:Methionine / Q000493:pharmacokinetics; D008845:Microinjections; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D017966:Pyramidal Cells / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D014404:Tubulin / Q000378:metabolism
D000199:Actins; D003598:Cytoskeletal Proteins; D009419:Nerve Tissue Proteins; D014404:Tubulin; D008715:Methionine