| 1993 |
E-MAP-115 (MAP7) was identified as a novel microtubule-associated protein of 115 kDa with nucleotide-insensitive binding to microtubules. Its microtubule-binding site was localized to a basic alpha-helical region in the NH2-terminal domain using in vitro microtubule-binding assays and expression of mutant polypeptides. Overexpression of this domain in fibroblasts rendered microtubules stable to nocodazole, identifying it as a microtubule-stabilizing protein. |
In vitro microtubule-binding assays, mutant polypeptide expression, nocodazole resistance assay |
The Journal of cell biology |
High |
8408219
|
| 1995 |
Binding of E-MAP-115 (MAP7) to microtubules is regulated by cell cycle-dependent phosphorylation. In mitotic HeLa cells, E-MAP-115 is hyperphosphorylated (~15-fold increase in 32P incorporation) specifically on threonine residues, and this hyperphosphorylated form cannot stably bind microtubules in vitro. The protein dissociates from microtubules in early prophase and progressively reassociates after late prophase, suggesting phosphorylation drives mitotic spindle assembly by releasing MAP7 from interphase microtubules. |
32P metabolic labeling, SDS-PAGE mobility shift, in vitro microtubule-binding assay with mitotic vs. interphase protein, immunolabeling across cell cycle stages |
The Journal of cell biology |
High |
7490279
|
| 1999 |
E-MAP-115 (ensconsin/MAP7) associates dynamically with microtubule lattices immediately upon polymerization and dissociates concomitant with depolymerization in vivo, as shown by dual-wavelength time-lapse fluorescence imaging with GFP-EMTB chimeras. Cells expressing four to ten times the physiological level of MAP7 showed microtubule dynamics indistinguishable from untransfected cells, establishing that MAP7 at physiological levels is NOT a microtubule stabilizer in vivo. |
Dual-wavelength time-lapse fluorescence live imaging, stable GFP-EMTB chimera cell lines, microinjection with labeled tubulin |
Journal of cell science |
High |
10564643
|
| 2000 |
Genetic knockout of E-MAP-115 (MAP7) in mice causes male sterility due to deformation of spermatid nuclei and gradual loss of germ cells. Microtubule associations in the manchette of spermatids and in Sertoli cells were morphologically abnormal in null mice, establishing an essential in vivo role for MAP7 in microtubule organization required for spermatogenesis. |
Gene trap mutagenesis generating null allele, histological and morphological analysis of testes, immunolabeling of microtubule structures |
Genes & development |
High |
10837026
|
| 2017 |
MAP7 is expressed at the onset of axon collateral branch formation in dorsal root ganglion (DRG) neurons, localizes to branch points colocalizing with stable microtubules, and its loss or overexpression alters axon branching. Domain analysis of a gain-of-function truncated MAP7 mutant mouse showed the amino-terminal half is responsible for branch formation independently of kinesin-1 interaction, establishing MAP7 as a regulator of axon collateral branch morphogenesis. |
shRNA knockdown, overexpression, domain truncation analysis, time-lapse imaging, spontaneous mutant mouse analysis, in vitro DRG culture branching assays |
The Journal of neuroscience |
High |
28069923
|
| 2018 |
MAP7 recruits kinesin-1 to microtubules via direct interaction, using a kinesin-1-binding domain distinct from its two microtubule-binding sites. The kinesin-1-interacting domain is required for axon and branch growth but not branch formation, while both microtubule-binding sites are required for branch formation. MAP7 localizes to branch sites and dynamically recruits kinesin-1, altering organelle transport behaviors (pause/speed switching). |
Structure-function analysis with domain deletions, live-cell imaging of organelle transport, co-immunoprecipitation, sensory neuron culture knockdown/overexpression |
eLife |
High |
30132755
|
| 2018 |
MAP7 and its paralog MAP7D1 bind Disheveled (Dvl), direct its cortical localization, and facilitate cortical targeting of microtubule plus-ends in response to Wnt5a signaling. Wnt5a signaling also promotes MAP7/7D1 movement toward MT plus-ends, and depletion of KIF5B (Kinesin-1) abolishes this MAP7/7D1 dynamics and Disheveled localization. This MAP7-Disheveled feedback loop and its role in Wnt5a signaling is evolutionarily conserved (shown also in Drosophila Ensconsin/Disheveled). |
Co-IP (MAP7/Dvl interaction), shRNA knockdown, live imaging, cortical localization assay, Drosophila genetic analysis |
EMBO reports |
Medium |
29880710
|
| 2019 |
MAP7 shifts organelle (phagosome) transport toward the microtubule plus-end (~80% plus-end directed vs. ~50% without MAP7) by increasing the binding rate of kinesin-1 to microtubules without altering the force of individual motors. For ensembles of kinesin-1, MAP7 leads to more simultaneously engaged motors generating force, thereby biasing transport direction. |
In vitro phagosome motility reconstitution, single-molecule imaging of kinesin-1, optical trapping force measurements |
The Journal of biological chemistry |
High |
31085585
|
| 2019 |
MAP7 prevents axon branch retraction by binding to the acetylated/stable region of individual microtubules while avoiding the dynamic plus-end, creating a boundary that prevents microtubule depolymerization and rescues polymerization. This boundary function maintains stable microtubules at branch junctions and can prevent branch retraction caused by laser-induced severing or nocodazole treatment. |
Live-cell imaging, MAP7 depletion (shRNA), laser-induced microtubule severing, single-microtubule dynamics analysis, colocalization with acetylated tubulin |
The Journal of neuroscience |
High |
31391261
|
| 2022 |
Cryo-EM and single-molecule imaging revealed that the MAP7 microtubule-binding domain (MTBD) binds as an extended alpha-helix between the protofilament ridge and lateral contact site, partially overlapping with the kinesin-1 binding site, thereby inhibiting kinesin-1 motility when MTs are saturated with MAP7. However, the projection domain of MAP7 tethers kinesin-1 to the MT, preventing dissociation and facilitating binding to available neighboring sites, resulting in biphasic (concentration-dependent) regulation of kinesin-1 by MAP7. |
Cryo-electron microscopy, single-molecule imaging, structure determination of MAP7-MT complex |
Science |
High |
35050657
|
| 2023 |
MAP7 and MAP7D1 interact with several DNA double-strand break repair proteins including RAD50, BRCA1, and 53BP1 (identified by quantitative proteomics). Downregulation of MAP7 and MAP7D1 in G1-arrested cells impairs DNA repair, reduces RAD50 recruitment to chromatin, and disrupts 53BP1 localization to damage sites, establishing a novel function for MAP7 in DNA double-strand break repair in the G1 phase. |
Quantitative proteomics, Co-IP, shRNA knockdown, chromatin fractionation, immunofluorescence of repair foci, gamma-irradiation assays |
iScience |
Medium |
36852271
|
| 2024 |
MAP7 promotes tubulin acetylation and inhibits tubulin detyrosination, thereby modulating the tubulin code. These MAP7-driven tubulin PTM changes alter intracellular cargo transport, enabling cellular adaptation to osmotic stress. Human epithelial cells modulate MAP7 association with microtubules in response to changes in cytoplasmic density/osmolarity. |
Live-cell imaging, ex vivo enzymatic assays, in vitro reconstitution, quantification of tubulin PTMs under osmotic perturbation |
Developmental cell |
High |
38574732
|
| 2024 |
Solid-state and solution-state NMR combined with electron microscopy, fluorescence anisotropy, and isothermal titration calorimetry revealed that MAP7 MTBD binds the MT lattice through interactions extending beyond a single tubulin dimer and including interactions with tubulin C-terminal tails, establishing the atomic-level binding mode of MAP7 to microtubules. |
Solid-state and solution-state NMR, electron microscopy, fluorescence anisotropy, isothermal titration calorimetry |
Nature communications |
High |
38431715
|
| 2025 |
MAP7 enhances kinesin-1 engagement with microtubules (increasing run length and MT recruitment) without significantly relieving kinesin-1 auto-inhibition, while BicD relieves auto-inhibition. The combination of BicD and MAP7 produces the most robust kinesin-1 activation, demonstrating complementary mechanisms where MAP7 enables activated kinesin-1 motors to productively engage microtubules. |
Single-molecule motility assays with purified Drosophila proteins, quantitative analysis of motor processivity and run length |
Traffic (Copenhagen, Denmark) |
High |
40384341
|
| 2025 |
Opening of the kinesin-1 heterotetrameric complex (transition from closed/autoinhibited to open state) facilitated by cargo SLiM binding to KLC TPR domains promotes binding to MAP7 on microtubules, establishing that MAP7 binding to kinesin-1 is allosterically coupled to the cargo-activated open conformation of the motor. |
Protein design, computational modelling, biophysical analysis, electron microscopy of kinesin-1 holoenzyme |
bioRxivpreprint |
Medium |
bio_10.1101_2025.04.08.647705
|
| 2025 |
MAP7 localizes preferentially to apical microtubules in Sertoli cells and MAP7-decorated microtubules become increasingly aligned along the tubule axis during apical domain maturation. In Map7-deficient testes, microtubule higher-order organization is disrupted with persistent luminal F-actin accumulation. Proteomic analysis identified non-muscle myosin II heavy chains MYH9 and MYH10 as MAP7-associated proteins, and MYH9 becomes enriched at luminal regions where microtubules and F-actin converge in a MAP7-dependent manner. |
Native-tissue imaging, conditional knockout, proteomics, single-cell RNA sequencing, immunofluorescence |
bioRxivpreprint |
Medium |
bio_10.1101_2025.09.16.676497
|
| 2020 |
MAP7 interacts with RC3H1 (identified by Co-IP) in cervical cancer cells, and the two proteins cooperatively enhance cyclin D1/cyclin B1 expression and facilitate cell-cycle progression via activation of canonical IKK/NF-κB signaling (increased P-IKK and P-p65). |
Co-immunoprecipitation, knockdown of MAP7 and RC3H1, western blot for NF-κB pathway components, xenograft model |
Biochemical and biophysical research communications |
Low |
32446391
|
| 2025 |
FBXW7 promotes K48-linked polyubiquitination of MAP7, destabilizing MAP7 protein, as demonstrated by stability analysis and immunoprecipitation assays. This FBXW7-MAP7 axis regulates malignant cell phenotypes and paclitaxel sensitivity in lung adenocarcinoma. |
Co-immunoprecipitation, protein stability assay, ubiquitination assay, knockdown/overexpression |
European journal of medical research |
Medium |
41382187
|