EXPRESSION OF THE P150(GLUED) COMPONENT OF THE DYNACTIN COMPLEX IN DEVELOPING AND ADULT-RAT BRAIN

p150(Glued) is component of the dynactin (Glued) complex that has been shown in vitro to be a required activator of cytoplasmic dynein-media ted transport of vesicles along microtubules and, thus, may be an esse ntial component of retrograde axonal transport. In vivo, a dominant mu tation in the Drosophila homologue of p150(Glued) induces aberrant neu ronal development when heterozygous and is lethal when homozygous. In order to characterize the role of the dynactin complex in the developm ent and function of vertebrate neurons, the distribution of the p150(G lued) message was examined via in situ hybridization to serial section s of adult rat brain and to a developmental series of sections. In the adult rat brain, the most intense hybridization observed with the p15 0(Glued) probe was in the pyramidal cells of the hippocampus proper, t he dentate granule neurons, the cingulate and piriform cortices, the v entromedial hypothalamus, and the granular cell layer of the cerebellu m. White-matter fiber tracts and the neuropil were generally devoid of signal. The data indicate that the mRNA encoding p150(Glued) is highl y enriched in the cell bodies of neurons within the central nervous sy stem. In developing rat, p150(Glued) is expressed at very high levels in neural tissue from the earliest time points assayed. Particularly i ntense hybridization was observed in the multiple layers of the retina , which is consistent with the phenotype of the Drosophila mutation. T herefore, the distributions observed via in situ hybridization are con sistent with an essential role for p150(Glued) in retrograde axonal tr ansport. (C) 1995 Wiley-Liss, Inc.