both in regenerates and in developing limbs of newts larvae mesenchymal cells begin to differentiate into myoblasts , which contain both thin ( 7 nm ) and thick ( 14 nm ) filaments , which are often associated with microtubules , developing a cytoskeletal network , which contribute directly to the shape of myoblasts and a linear alignment of the myofibrils .
C0026046
microtubules
C0010853
cytoskeletal