Structural basis for two-way communication between dynein and microtubules

Abstract

The movements of cytoplasmic dynein on microtubule (MT) tracks is achieved by two-way communication between the microtubule-binding domain (MTBD) and the ATPase domain of dynein via an a-helical coiled-coil stalk, but the structural basis of this communication remains elusive. Here, we regulated MTBD either in high-affinity or low-affinity states by introducing a disulfide bond between the coiled-coils and analyzed the resulting structures by NMRand cryo-EM.In the MT-unbound state, the affinity changes of MTBD were achieved by sliding of the N-terminal α-helix by one half-turn, which suggests that structural changes propagate from the ATPase-domain to MTBD. In addition, cryo-EM analysis showed that MT binding induced further sliding of the N-terminal α-helix even without the disulfide bond, which suggests the MT-induced conformational changes propagate toward the ATPase domain. Based on differences in the MT-binding surface between the high-and low-affinity states, we propose a potential mechanism for the directional bias of dynein movement on MT tracks. Nishida et al.

The mechanism of motor inhibition by microtubule-associated proteins

“…To determine whether the MAP7 binding site overlaps with motor binding sites, we superimposed previously determined structures of kinesin and dynein bound to the MT onto our MAP7 structure (Figure 2A). Surprisingly, there was a clear overlap between the MAP7 density with the binding sites of both kinesin and dynein at the intra-dimer interface between tubulin subunits (Lacey et al, 2019;Nishida et al, 2020;Redwine et al, 2012;Shang et al, 2014). In comparison, the MT-bound structure of tau (Kellogg et al, 2018) overlaps with the kinesin binding site, but not with the MTBD of dynein.…”

Regulatory mechanisms of the dynein-2 motility by post-translational modification revealed by MD simulation

“…This model was already contained whole motor domain, and the sequence was DYHC2, so we used MODELLER only for modeling disordered region. Also, for the ADP state dynein which took high-affinity MTBD was modeled by combining the three models taken from the PDB ID: 3VKH (44) for AAA+ and stalk, 3J1T (45) for stalk and MTBD, and 6KIQ (46) for MTBD and the interface with MT in the following protocol. At first, 3VKH was the X-ray crystal structure of Dictyostelium discoideum cytoplasmic dynein-1.…”

The MAP She1 coordinates directional spindle positioning by spatially restricting dynein activity

“…Our prior in vitro work revealed that She1 exhibits higher affinity for the nucleotide-free conformational state of the dynein motor domain (the apo state) 10 . Given She1's interaction with the dynein MTBD, and its preferential binding to the high microtubule affinity state of the MTBD 10 , this indicates that She1 exhibits higher affinity for dynein when it is bound to microtubules during a processive run 47,48 . Although the purpose of this binding specificity is not understood, it may play a role in the mechanism by which She1 regulates dynein activity.…”