title: Myosin light chain kinase (MLCK) regulates cell migration in a myosin regulatory light chain phosphorylation-independent mechanism.
abstract: Myosin light chain kinase (MLCK) has long been implicated in the myosin phosphorylation and force generation required for cell migration. Here, we surprisingly found that the deletion of MLCK resulted in fast cell migration, enhanced protrusion formation, and no alteration of myosin light chain phosphorylation. The mutant cells showed reduced membrane tether force and fewer membrane F-actin filaments. This phenotype was rescued by either kinase-dead MLCK or five-DFRXXL motif, a MLCK fragment with potent F-actin-binding activity. Pull-down and co-immunoprecipitation assays showed that the absence of MLCK led to attenuated formation of transmembrane complexes, including myosin II, integrins and fibronectin. We suggest that MLCK is not required for myosin phosphorylation in a migrating cell. A critical role of MLCK in cell migration involves regulating the cell membrane tension and protrusion necessary for migration, thereby stabilizing the membrane skeleton through F-actin-binding activity. This finding sheds light on a novel regulatory mechanism of protrusion during cell migration.
authors.affiliation: From the Model Animal Research Center, Key Laboratory of Model Animal for Disease Study of Ministry of Education, Nanjing University, Nanjing 210061, P.R. China.
authors.forename: Chen
authors.initials: C
authors.lastname: Chen
authors.affiliation: From the Model Animal Research Center, Key Laboratory of Model Animal for Disease Study of Ministry of Education, Nanjing University, Nanjing 210061, P.R. China.
authors.forename: Tao
authors.initials: T
authors.lastname: Tao
authors.affiliation: School of Electronics Engineering and Computer Science, Key Laboratory for the Physics & Chemistry of Nanodevices of Ministry of Education, Peking University, Beijing 100871, P.R. China, and.
authors.forename: Cheng
authors.initials: C
authors.lastname: Wen
authors.affiliation: From the Model Animal Research Center, Key Laboratory of Model Animal for Disease Study of Ministry of Education, Nanjing University, Nanjing 210061, P.R. China.
authors.forename: Wei-Qi
authors.initials: WQ
authors.lastname: He
authors.affiliation: From the Model Animal Research Center, Key Laboratory of Model Animal for Disease Study of Ministry of Education, Nanjing University, Nanjing 210061, P.R. China.
authors.forename: Yan-Ning
authors.initials: YN
authors.lastname: Qiao
authors.affiliation: From the Model Animal Research Center, Key Laboratory of Model Animal for Disease Study of Ministry of Education, Nanjing University, Nanjing 210061, P.R. China.
authors.forename: Yun-Qian
authors.initials: YQ
authors.lastname: Gao
authors.affiliation: From the Model Animal Research Center, Key Laboratory of Model Animal for Disease Study of Ministry of Education, Nanjing University, Nanjing 210061, P.R. China.
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
authors.affiliation: From the Model Animal Research Center, Key Laboratory of Model Animal for Disease Study of Ministry of Education, Nanjing University, Nanjing 210061, P.R. China.
authors.forename: Pei
authors.initials: P
authors.lastname: Wang
authors.affiliation: From the Model Animal Research Center, Key Laboratory of Model Animal for Disease Study of Ministry of Education, Nanjing University, Nanjing 210061, P.R. China.
authors.forename: Cai-Ping
authors.initials: CP
authors.lastname: Chen
authors.affiliation: From the Model Animal Research Center, Key Laboratory of Model Animal for Disease Study of Ministry of Education, Nanjing University, Nanjing 210061, P.R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
authors.affiliation: School of Life Science, Nanjing Normal University, Nanjing 210009, P.R. China.
authors.forename: Hua-Qun
authors.initials: HQ
authors.lastname: Chen
authors.affiliation: School of Electronics Engineering and Computer Science, Key Laboratory for the Physics & Chemistry of Nanodevices of Ministry of Education, Peking University, Beijing 100871, P.R. China, and.
authors.forename: An-Pei
authors.initials: AP
authors.lastname: Ye
authors.affiliation: From the Model Animal Research Center, Key Laboratory of Model Animal for Disease Study of Ministry of Education, Nanjing University, Nanjing 210061, P.R. China, pengyj@nicemice.cn.
authors.forename: Ya-Jing
authors.initials: YJ
authors.lastname: Peng
authors.affiliation: From the Model Animal Research Center, Key Laboratory of Model Animal for Disease Study of Ministry of Education, Nanjing University, Nanjing 210061, P.R. China, School of Life Science, Nanjing Normal University, Nanjing 210009, P.R. China zhums@nju.edu.cn.
authors.forename: Min-Sheng
authors.initials: MS
authors.lastname: Zhu
mesh_terms: D008841:Actin Cytoskeleton / Q000737:chemistry / Q000378:metabolism*; D000199:Actins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000256:Adenoviridae / Q000235:genetics; D020816:Amino Acid Motifs; D000818:Animals; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism*; D002465:Cell Movement; D005786:Gene Expression Regulation; D005822:Genetic Vectors; D007583:Jejunum / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000378:metabolism*; D009219:Myosin-Light-Chain Kinase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D061251:Primary Cell Culture; D011485:Protein Binding; D015398:Signal Transduction; D013500:Surface Tension; D014162:Transfection
chemical_list: D000199:Actins; D009219:Myosin-Light-Chain Kinase
keywords: Actin; Cell Migration; Cell Motility; Cortical Cytoskeleton; Cytoskeleton; Membrane Protrusion; Membrane Tension; Myosin; Myosin Light Chain Kinase; Plasma Membrane