The interaction between cytoplasmic dynein and dynactin is required for fast axonal transport

Fast axonal transport is characterized by the bidirectional, microtubule-based movement of membranous organelles. Cytoplasmic dynein is necessary but not sufficient for retrograde transport directed from the synapse to the cell body. Dynactin is a heteromultimeric protein complex, enriched in neurons, that binds to both microtubules and cytoplasmic dynein. To determine whether dynactin is required for retrograde axonal transport, we examined the effects of anti-dynactin antibodies on organelle transport in extruded axoplasm. Treatment of axoplasm with antibodies to the p150Glued subunit of dynactin resulted in a significant decrease in the velocity of microtubule-based organelle transport, with many organelles bound along microtubules. We examined the molecular mechanism of the observed inhibition of motility, and we demonstrated that antibodies to p150Glued disrupted the binding of cytoplasmic dynein to dynactin and also inhibited the association of cytoplasmic dynein with organelles. In contrast, the anti-p150Glued antibodies had no effect on the binding of dynactin to microtubules nor on cytoplasmic dynein-driven microtubule gliding. These results indicate that the interaction between cytoplasmic dynein and the dynactin complex is required for the axonal transport of membrane-bound vesicles and support the hypothesis that dynactin may function as a link between the organelle, the microtubule, and cytoplasmic dynein during vesicle transport.

Lecons d'anatomie comparée / de Georges Cuvier ; recueillies et publiées par m. Duméril.

8

A commentary on the scientific writings of J. Willard Gibbs.

1

Plant species, biomass and environmental characteristics of relevés along the North America Arctic bioclimate gradient

Question: How do interactions between the physical environment and biotic properties of vegetation influence the formation of small patterned-ground features along the Arctic bioclimate gradient? Location: At 68° to 78°N: six locations along the Dalton Highway in arctic Alaska and three in Canada (Banks Island, Prince Patrick Island and Ellef Ringnes Island). Methods: We analysed floristic and structural vegetation, biomass and abiotic data (soil chemical and physical parameters, the n-factor [a soil thermal index] and spectral information [NDVI, LAI]) on 147 microhabitat releves of zonalpatterned-ground features. Using mapping, table analysis (JUICE) and ordination techniques (NMDS). Results: Table analysis using JUICE and the phi-coefficient to identify diagnostic species revealed clear groups of diagnostic plant taxa in four of the five zonal vegetation complexes. Plant communities and zonal complexes were generally well separated in the NMDS ordination. The Alaska and Canada communities were spatially separated in the ordination because of different glacial histories and location in separate floristic provinces, but there was no single controlling environmental gradient. Vegetation structure, particularly that of bryophytes and total biomass, strongly affected thermal properties of the soils. Patterned-ground complexes with the largest thermal differential between the patterned-ground features and the surrounding vegetation exhibited the clearest patterned-ground morphologies.

Half hours with a naturalist: rambles near the shore.

Mode of access: Internet.

Hughes's illustrated anecdotal natural history /

Mode of access: Internet.

Composition and digestibility of corn ensilage, cowpea ensilage, soja bean ensilage, and corn-fodder /

Caption title.

Azimuths of the sun for latitudes extending to 70 degrees from the equator.

The first edition has title: Azimuth tables ... By Lieutenant S. Schroeder ... and Master W. H. H. Southerland ... Washington, Govt. print. off., 1882.

When the sleeper wakes.

Mode of access: Internet.

By England's aid: or, The freeing of the Netherlands. (1585-1604).

Mode of access: Internet.

Kaye's and Malleson's History of the Indian mutiny of 1857-8 /

Vols. 3-6, by Malleson, first appeared under title: History of the Indian mutiny, 1857-1858, commencing from the close of the second volume of Sir John Kaye's History of the Sepoy War.

Figure drawing,

A companion volume to the author's Figure composition. The two volumes were originally published in one volume, under title: Figure drawing and composition.

The bibliographer's manual of English literature containing an account of rare, curious, and useful books, published in or relating to Great Britain and Ireland, from the invention of printing; with bibliographical and critical notices, collations of the rarer articles, and the prices at which they have been sold.

Vol. 6 has special title: Appendix to the Bibliographer's manual of English literature. Containing an account of books issued by literary and scientific societies and printing clubs; books printed at private presses; privately printed series; and the principal literary and scientific serials. Comp. by Henry G. Bohn ...