TY - JOUR T1 - Neurofilament Transport <em>In Vivo</em> Minimally Requires Hetero-Oligomer Formation JF - The Journal of Neuroscience JO - J. Neurosci. SP - 9452 LP - 9458 DO - 10.1523/JNEUROSCI.23-28-09452.2003 VL - 23 IS - 28 AU - Aidong Yuan AU - Mala V. Rao AU - Asok Kumar AU - Jean-Pierre Julien AU - Ralph A. Nixon Y1 - 2003/10/15 UR - http://www.jneurosci.org/content/23/28/9452.abstract N2 - Neurofilament assembly requires at minimum the polymerization of neurofilament light chain (NF-L) with either neurofilament medium chain (NF-M) or neurofilament heavy chain (NF-H) subunits, but requirements for their axonal transport have long been controversial. Using a gene deletion approach, we generated mice containing only NF-L or NF-M. In vivo pulse radiolabeling analyses in retinal ganglion cell neurons revealed that NF-L alone is incapable of efficient transport, whereas nearly one-half of the normal level of NF-M is transported along optic axons in the absence of the other triplet subunits. Under these conditions, however, NF-M transport is completely abolished by deleting α-internexin. Our results strongly suggest that efficient neurofilament protein transport in vivo minimally requires hetero-oligomer formation. They also show that NF-M can partner with intermediate filament proteins other than the NF-H and NF-L subunits in neurons to support slow transport and possibly other functions of neuronal intermediate filaments. ER -