J Biol Chem. 2003 Dec 19;278(51):51448-53. Epub 2003 Sep 28.

Microtubule-associated [corrected] protein 7 increases the membrane expression of transient receptor potential vanilloid 4 (TRPV4).External 2231691f894ba696de1310221b0a0dbbb31a7251e75115c265587c3d9d5f507c

Suzuki, M., Hirao, A., Mizuno, A.,
["Department of Pharmacology, Jichi Medical School 3311-1, Yakushiji, Minamikawachi, Tochigi, 329-0498, Japan. macsuz@jichi.ac.jp"]
The molecular mechanism of the transmission of changes in the shape of the cell surface to ion channels remains obscure. Ca2+ influx induced by cell deformity is inhibited by actin-freezing reagents, suggesting that the actin microfilament couples with an ion channel. Transient receptor potential vanilloid 4 (TRPV4) is a candidate in the calcium-permeable, swelling-activated mechanosensitive channel in heterogeneously expressed cells. To investigate the mechanosensitive molecular complex, we found that microtubule-associated protein 7 (MAP7) is the mouse TRPV4 C-terminal binding protein. MAP7 was coimmunoprecipitated with TRPV4. The results of a pull-down assay demonstrated that the alignment of amino acids 798-809 of TRPV4 was important in this interaction. TRPV4 and MAP7 colocalized in the lung and kidney. The coexpression of these two molecules resulted in the redistribution of TRPV4 toward the membrane and increased its functional expression. The alignment of amino acids 798-809 of TRPV4 was also important in the functional expression. The activated current was abolished by actin-freezing but not by microtubule-freezing reagents. We therefore believe that MAP7 may enhance the membrane expression of TRPV4 and possibly link cytoskeletal microfilaments.
PMID: 14517216External 2231691f894ba696de1310221b0a0dbbb31a7251e75115c265587c3d9d5f507c
Screening Toggle 893349bafcc528f8346c51dc3420151d67b0126b2c122dd1017121c03fa0f69b
  Experimental screening Non-experimental screening Reference
TRP channel construct Interactor source
TRP channel Interactor Method Species Region Species Organ/tissue Sample type
TRPV4 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 MAP7 Yeast two-hybrid Mouse 783-871 Mouse Kidney cDNA library 14517216
(Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4: click the arrow icon to show interactions only between the corresponding TRP channel and the interactor)
Validation: In vitro validation Toggle 893349bafcc528f8346c51dc3420151d67b0126b2c122dd1017121c03fa0f69b
  Assay with recombinant proteins Reference
TRP channel construct Interactor construct
TRP channel Interactor Method Species Region Expression system Species Region Expression system
TRPV4 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 MAP7 Fusion protein-pull down assay Mouse Full-length HEK293 lysates Mouse Full-length In vitro translation 14517216
(Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4: click the arrow icon to show interactions only between the corresponding TRP channel and the interactor)
Validation: In vivo validation Toggle 893349bafcc528f8346c51dc3420151d67b0126b2c122dd1017121c03fa0f69b
  Assay with endogenous proteins Assay with overexpressed proteins Reference
Cell or tissue Cell or tissue TRP channel construct Interactor construct
TRP channel Interactor Method Species Region Species Region
TRPV4 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 MAP7 Co-immunoprecipitation Mouse renal tissue 14517216
TRPV4 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 MAP7 Co-immunoprecipitation HEK293 Mouse 785-808 Mouse Full-length 14517216
TRPV4 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 MAP7 Co-immunofluorescence staining Mouse lung section 14517216
TRPV4 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 MAP7 Co-immunofluorescence staining Mouse kidney section 14517216
TRPV4 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 MAP7 Co-immunofluorescence staining HEK293 Mouse Full-length Mouse Full-length 14517216
(Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4: click the arrow icon to show interactions only between the corresponding TRP channel and the interactor)
Functional consequence Toggle 893349bafcc528f8346c51dc3420151d67b0126b2c122dd1017121c03fa0f69b
TRP channel Interactor Method Post-translational modification Subcellular trafficking Activity Reference
TRPV4 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 MAP7 Cell surface biotinylation Increase in plasma membrane level 14517216
TRPV4 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 MAP7 Patch clamp Activation 14517216
(Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4: click the arrow icon to show interactions only between the corresponding TRP channel and the interactor)
TRP / Interactor

To prevent spam comments, we use reCAPTCHA. Please type correct words into the following box.