title: Heat stress increases delivery of a unique sub-population of proteins conveyed by fast axonal transport.
abstract: The effect of heat stress on protein synthesis and fast axonal transport was examined in vitro in bullfrog dorsal root ganglion (DRG) and associated spinal/sciatic nerve. Qualitative and quantitative changes of individual 35S-methionine-labelled proteins were determined following DRG labelling and fast transport in respective nerves via two-dimensional gel electrophoresis/autoradiography. Elevation of temperature from 18 degrees C to 33 degrees C for up to 6 hr resulted in a marked increase in synthesis of five individual DRG species of approximately 74,000 daltons that comigrate with heat shock proteins (HSPs). A quantitative comparison of species within this subset revealed two subgroups differentially affected by stress. The three most basic proteins were induced to approximately 1300% of unstressed controls after 6 hr of stress, while the two most acidic species demonstrated an increase to only 300% of controls over the same period. The relative abundance of 25 additional DRG proteins were uneffected by heat stress. Of 70 35S-labelled fast-transported proteins similarly analyzed, 15, comprising 5 families, were consistently transported at greater than 150% of controls following up to 6 hr of heat stress. Over this period all 15 proteins shared a similar profile of abundance relative to non-induced proteins. Transport was elevated to the greatest extent after 2 hr of stress, declined after 3 hr, and tended to rebound at later times. The remaining 55 fast-transported protein spots analyzed were unaffected. An increased delivery of this unique sub-population of 15 fast-transported proteins suggests a possible involvement in early cellular events that mediate heat stress in the nervous system.
authors: Division of Molecular Biology and Neural Regeneration, Nathan S. Kline Institute for Psychiatric Research, Orangeburg, New York.
authors: G C
authors: GC
authors: Stone
authors: M M
authors: MM
authors: Dougher
mesh_terms: D000818:Animals; D001370:Axonal Transport; D005727:Ganglia, Spinal / Q000378:metabolism* / Q000502:physiology; D006360:Heat-Shock Proteins / Q000096:biosynthesis / Q000378:metabolism; D006358:Hot Temperature; D066298:In Vitro Techniques; D008970:Molecular Weight; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000378:metabolism*; D011892:Rana catesbeiana; D013312:Stress, Physiological / Q000378:metabolism*
chemical_list: D006360:Heat-Shock Proteins; D009419:Nerve Tissue Proteins