|
|
|
|
|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
|
Fig. 3. A Myod-generated feed-forward circuit temporally patterns gene expression
during skeletal muscle differentiation. Myod regulates the transcription of
the Mef2 isoforms, including Mef2d, and activates the p38 kinase pathway,
shown here mediated by factor X. Factor X might be the Akt2 kinase, which is
transcriptionally regulated by Myod and phosphorylates p38. The phosphorylated
p38 becomes an active kinase and phosphorylates Mef2d, permitting it to bind
and activate the myosin heavy chain (Myh3) gene together with Myod.
The Myh3 gene is not activated by Myod until Mef2d is expressed and
p38 is active (Penn et al.,
2004). The feed-forward mechanism regulates the activity of Myod
at a subset of promoters and imposes a temporal order on Myod-mediated gene
expression. This diagram uses the graphical language BioD
(Cook et al., 2001).
|
