TY - JOUR T1 - Characterization of TAG-63 and its role on axonal transport in <em>C. elegans</em> JF - bioRxiv DO - 10.1101/723338 SP - 723338 AU - Prerana Bhan AU - Muniesh Muthaiyan Shanmugam AU - Ding Wang AU - Odvogmed Bayansan AU - Chih-Wei Chen AU - Oliver Ingvar Wagner Y1 - 2019/01/01 UR - http://biorxiv.org/content/early/2019/08/04/723338.abstract N2 - Model organisms are increasingly used to study and understand how neurofilament (NF)-based neurological diseases develop. However, whether a NF homolog exists in C. elegans remains unclear. We characterize TAG-63 as a NF-like protein with sequence homologies to human NEFH carrying various coiled coils as well as clustered phosphorylation sites. TAG-63 also exhibits features of NFL such as a molecular weight of around 70 kD, the lack of KSP repeats and the ability to form 10 nm filamentous structures in transmission electron micrographs. An anti-NEFH antibody detects a band at the predicted molecular weight of TAG-63 in Western blots of whole worm lysates and this band cannot be detected in tag-63 knockout worms. A transcriptional tag-63 reporter expresses in a broad range of neurons, and various anti-NFH antibodies stain worm neurons with an overlapping expression of axonal vesicle transporter UNC-104(KIF1A). Cultured neurons grow shorter axons when incubating with drugs known to disintegrate the NF network and rhodamine-labeled in vitro reconstituted TAG-63 filaments disintegrate upon drug exposure. Speeds of UNC-104 motors are diminished in tag-63 mutant worms with visibly increased accumulations of motors along axons. UNC-104/TAG-63 and SNB-1/TAG-63 not only co-localize in neurons but also revealed positive BiFC (bimolecular fluorescence assay) signals. ER -