DYNLRB1 (dynein light chain roadblock-type 1) is an essential accessory subunit of the cytoplasmic dynein 1 motor complex required for microtubule-based transport. As a non-catalytic component, DYNLRB1 facilitates cargo linking and adapter protein recruitment to dynein 1. Beyond its canonical dynein role, DYNLRB1 functions in dynein-independent signaling pathways, particularly regulating MEK/ERK activation and R-Ras localization at the protruding edges of colorectal cancer cells 2. In sensory neurons, DYNLRB1 mediates retrograde axonal transport of FMRP-containing endolysosomal organelles and regulates their targeted degradation, controlling translational regulation of microtubule-associated proteins 3. DYNLRB1 is essential for neuronal survival; homozygous null mice are embryonic lethal, while conditional depletion in sensory neurons impairs axonal transport of lysosomes and retrograde signaling endosomes, compromising neuron survival 1. DYNLRB1 also interacts with Rab6 GTPases at the Golgi 4, the folate transporter RFC 5, and promotes protein aggregate clearance through interactions with NAGK 6, suggesting roles in neurodegenerative disease pathogenesis. Additionally, NAGK-SNRPN-DYNLRB1 interactions promote axodendritic branching and rescue impaired neuronal development in Prader-Willi syndrome models 7.