|
|
|
|
|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
|
Fig. 9. A two-phase model of muscle arm development. (A) Three myoblasts (red),
which juxtapose a motoneuron (green) during mid-embryogenesis. The nucleus of
the centre myoblast is shown. (B) Myoblasts either migrate away or are
displaced from the motoneuron, leaving a muscle arm membrane attachment
behind. This is the first phase of muscle arm development. (C) The activity of
unc-54/MHC-B and lev-11/tropomyosin are required to modify
the morphology of the embryonic muscle arm. (D) The myoblasts complete
differentiation, including the obliquely arranged sarcomeres (dark red lines
represent anisotropic bands). (E) After embryogenesis and early in larval
development, post-embryonic neurons develop (additional green lines). These
additional axons may induce larval muscle arm extension through the secretion
of a chemotropic cue. This is the second phase of muscle arm development and
is dependant on actin, unc-54/MHC-B, lev-11/tropomyosin and
the F-actin depolymerization activity of unc-60B/ADF/cofilin.
|
