Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P20366 (substance P)
 21,176 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Subcellular fractionation of rabbit optic nerve resolves three populations of membranes that are rapidly labelled in the axon. The lightest membranes are greater than 200 nm and are relatively immobile. The intermediate density membranes consist of 84 nm vesicles which disappear from the nerve with kinetics identical to those of the rapid component. A third population of membranes, displaying a distinct protein profile, is present in the most dense region of the gradient. Immunological characterization of these membranes suggests the following. (1) The lightest peak contains rapidly transported glucose transporter and most of the total glucose transporters present in the nerve; this peak is therefore enriched in axolemma. (2) The intermediate peak contains rapidly transported glucose transporters and synaptophysin, an integral synaptic vesicle protein, and about half of the total synaptophysin; this peak therefore contains transport vesicles bound for both the axolemma and the nerve terminal, and these subpopulations can be separated by immunoadsorption with specific antibodies against the aforementioned proteins. (3) The heaviest peak contains rapidly transported synaptophysin and tachykinin neuromodulators and about half of the total synaptophysin, and 80% of the total tachykinins present in the nerve; this peak appears to represent a class of synaptic vesicle precursor bound for the nerve terminal exclusively. (4) Synaptophysin is present in the membranes of vesicles carrying tachykinins. (5) Both the intermediate and the heaviest peaks are enriched in kinesin heavy chain, suggesting that both vesicle classes may be transported by the same mechanism.
 ...
PMID:Isolation and characterization of rapid transport vesicle subtypes from rabbit optic nerve. 182 59

We have previously demonstrated that the in vivo vitreal injection of an antisense oligonucleotide directed to the kinesin heavy chain inhibits retinal kinesin synthesis by 82% and concomitantly inhibits rapid transport of total protein into the optic nerve by 70%. These results establish a major role for kinesin in rapid axonal transport in vivo. Recently, the cloning of a family of kinesin-like molecules from the mammalian brain has been reported, and some of these proteins are also expressed in neurons. To assign to specific function to the kinesin heavy chain we inhibited the kinesin synthesis with an antisense kinesin oligonucleotide and assessed the axonal transport into the optic nerve of representative proteins from each of three vesicle classes that contain rapidly transported proteins. Marker proteins used were substance P for peptide-containing synaptic vesicles, the amyloid protein for plasma membrane precursor vesicles, and several integral synaptic vesicle proteins. Our results indicate that the major anterograde motor protein for all three vesicle classes utilizes kinesin heavy chain, although we discuss alternative explanations.
 ...
PMID:Inhibition of kinesin synthesis in vivo inhibits the rapid transport of representative proteins for three transport vesicle classes into the axon. 753 13

The functional significance of biochemical and immunochemical heterogeneity in neuronal kinesin remains uncertain. Confocal laser scanning microscopy, cytofluorimetric scanning, and immunoblots were used for quantitative analyses of axonal transport and cellular distribution of immunochemically distinct kinesin heavy chain isoforms (H1 and H2) in rat peripheral nerve and spinal cord. H1 and H2 immunoreactivities (IR) were observed in axons proximal to a crush as early as 1 hr after the crush operation and increased linearly with time, consistent with fast axonal transport of both. Only approximately 10% of the proximal accumulations of H1-IR and H2-IR accumulated distal to the crush, in contrast to synaptophysin-IR (approximately 70%). H2-IR was widely present in peripheral nervous system and virtually colocalized with synaptic vesicle proteins synaptophysin, synaptobrevin I, and SNAP-25 and two neuropeptides [calcitonin gene-related peptide (CGRP) and substance P (SP)], although H2-IR was weaker in spinal cord terminals. In contrast, H1-IR appeared preferentially enriched in large axons, probably motor and large sensory neurons, which contained synaptophysin-IR, synaptobrevin I-IR, SNAP-25-IR, and CGRP-IR. However, H1-IR was weak or absent from SP-containing thin and medium-sized axons. In addition, H1-IR appeared to be absent from spinal cord nerve terminals. H1- and H2-IR kinesins are both transported with fast axonal transport, and comparatively small amounts of kinesins are retrogradely transported. H2 was widely distributed in motor, sensory, and sympathetic neurons, whereas H1 was enriched in large motor and sensory neurons.
 ...
PMID:Axonal transport and distribution of immunologically distinct kinesin heavy chains in rat neurons. 1050 79