title: Ste20-like kinase SLK displays myofiber type specificity and is involved in C2C12 myoblast differentiation.
abstract: Cell growth and terminal differentiation are controlled by complex signaling cascades that regulate the expression of specific subsets of genes implicated in cell fate and morphogenic processes. We have recently cloned and characterized a novel Ste20-like kinase termed SLK that is associated with adhesion structures during cell adhesion and spreading. However, the specific function of SLK is poorly understood. To gain further insight into the role of SLK, we have characterized its activity, expression, and distribution in skeletal muscle and during the in vitro differentiation of C2C12 myoblasts. Although SLK is expressed ubiquitously in adult tissues, our results show that it is predominantly expressed in muscle masses during development. Furthermore, SLK activity is upregulated during the differentiation of C2C12 myoblasts. In addition, we have found that SLK localizes presynaptically at neuromuscular junctions and that it is preferentially expressed in types I and IIA myofibers at major myofibrillar striations. Supporting a role in myoblast function and differentiation, SLK expression is induced in Myf5- and Pax7-positive activated satellite cells during regeneration and expression of dominant negative SLK in C2C12 cultures impairs myoblast fusion, suggesting a role for SLK in muscle cell differentiation.
authors.affiliation: Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Storbeck
authors.forename: Kate
authors.initials: K
authors.lastname: Daniel
authors.forename: Yi-Hong
authors.initials: YH
authors.lastname: Zhang
authors.forename: John
authors.initials: J
authors.lastname: Lunde
authors.forename: Anthony
authors.initials: A
authors.lastname: Scime
authors.forename: Atsushi
authors.initials: A
authors.lastname: Asakura
authors.forename: Bernard
authors.initials: B
authors.lastname: Jasmin
authors.forename: Robert G
authors.initials: RG
authors.lastname: Korneluk
authors.forename: Luc A
authors.initials: LA
authors.lastname: Sabourin
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D015153:Blotting, Western; D002454:Cell Differentiation / Q000502:physiology; D002460:Cell Line; D005455:Fluorescent Antibody Technique; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics / Q000502:physiology; D018014:Gene Transfer Techniques; D007763:Lac Operon / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D018485:Muscle Fibers, Skeletal / Q000201:enzymology*; D032446:Myoblasts / Q000201:enzymology*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000502:physiology*; D017661:Receptors, Presynaptic / Q000502:physiology; D032496:Satellite Cells, Skeletal Muscle / Q000502:physiology; D015854:Up-Regulation / Q000235:genetics / Q000502:physiology; D000099317:Hippo Kinases
chemical_list: D017346:Protein Serine-Threonine Kinases; D017661:Receptors, Presynaptic; C402650:SLK protein, mouse; D000099317:Hippo Kinases