title: Myocyte differentiation and body wall muscle regeneration in the planarian Girardia tigrina.
abstract: Freshwater planarians (Platyhelminthes, Turbellaria) show a great degree of morphological plasticity, making them a useful model for studying cell differentiation and pattern restoration processes during regeneration. Using confocal microscopy and a monoclonal antibody specific for muscle cells (TMUS-13), we have monitored the restoration of the body wall musculature during head regeneration in whole-mount organisms. Our results show that until the 4th day of regeneration the blastema is occupied by very disorganized muscle fibers, that from this moment become progressively organized restoring the original muscle pattern. In addition to recognizing mature muscle cells, TMUS-13 also recognizes differentiating myocytes, allowing us to trace the origin of newly formed muscle cells. We report that myocytes are detected in the postblastema region as early as day 1 of regeneration. This is the first demonstration that, in addition to serving as a proliferative zone as previously described, overt differentiation begins in the postblastema, at least for muscle cells. We also show that the TMUS13 antigen is the myosin heavy-chain gene from planarians.
authors.affiliation: Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Av. Diagonal 645, E-08071 Barcelona, Catalonia, Spain, , , , , , ES.
authors.forename: F
authors.initials: F
authors.lastname: Cebrià
authors.affiliation: Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Av. Diagonal 645, E-08071 Barcelona, Catalonia, Spain, , , , , , ES.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Vispo
authors.affiliation: Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Av. Diagonal 645, E-08071 Barcelona, Catalonia, Spain, , , , , , ES.
authors.forename: P
authors.initials: P
authors.lastname: Newmark
authors.affiliation: Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Av. Diagonal 645, E-08071 Barcelona, Catalonia, Spain, , , , , , ES.
authors.forename: David
authors.initials: D
authors.lastname: Bueno
authors.affiliation: Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Av. Diagonal 645, E-08071 Barcelona, Catalonia, Spain, , , , , , ES.
authors.forename: Rafael
authors.initials: R
authors.lastname: Romero
keywords: Key words Planarian; Muscle system; Myocyte differentiation; Myosin heavy chain; Regeneration