KIF1Bbeta- and KIF1A-mediated axonal transport of presynaptic regulator Rab3 occurs in a GTP-dependent manner through DENN/MADD.
Synaptic proteins are synthesized in the cell body and transported down the axon by microtubule-dependent motors. We previously reported that KIF1Bbeta and KIF1A motors are essential for transporting synaptic vesicle precursors; however the mechanisms that regulate transport, as well as cargo recognition and control of cargo loading and unloading remain largely unknown. Here, we show that DENN/MADD (Rab3-GEP) is an essential part of the regulation mechanism through direct interaction with the stalk domain of KIF1Bbeta and KIF1A. We also show that DENN/MADD binds preferentially to GTP-Rab3 and acts as a Rab3 effector. These molecular interactions are fundamental as sequential genetic perturbations revealed that KIF1Bbeta and KIF1A are essential for the transport of DENN/MADD and Rab3, whereas DENN/MADD is essential for the transport of Rab3. GTP-Rab3 was more effectively transported than GDP-Rab3, suggesting that the nucleotide state of Rab3 regulates axonal transport of Rab3-carrying vesicles through preferential interaction with DENN/MADD.
Niwa
Shinsuke
S
Department of Cell Biology and Anatomy, Graduate School of Medicine, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan.
Tanaka
Yosuke
Y
Hirokawa
Nobutaka
N
D000256:Adenoviridae / Q000235:genetics; D001370:Axonal Transport / Q000502:physiology*; D002460:Cell Line; D053418:Death Domain Receptor Signaling Adaptor Proteins / Q000378:metabolism*; D005822:Genetic Vectors; D005982:Glutathione Transferase / Q000378:metabolism; D020662:Guanine Nucleotide Exchange Factors / Q000378:metabolism*; D006160:Guanosine Triphosphate / Q000378:metabolism; D007150:Immunohistochemistry; D007668:Kidney / Q000166:cytology; D016547:Kinesins / Q000737:chemistry / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D034622:RNA Interference; D011994:Recombinant Proteins / Q000378:metabolism; D013572:Synaptic Vesicles / Q000378:metabolism / Q000502:physiology; D014162:Transfection; D020692:rab3 GTP-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D053418:Death Domain Receptor Signaling Adaptor Proteins; D020662:Guanine Nucleotide Exchange Factors; C470243:KIF11 protein, human; C094065:KIF1A protein, human; C105852:MADD protein, human; D011994:Recombinant Proteins; D006160:Guanosine Triphosphate; D005982:Glutathione Transferase; D016547:Kinesins; D020692:rab3 GTP-Binding Proteins