ZFIN ID: ZDB-PUB-040218-1
The B-cell maturation factor Blimp-1 specifies vertebrate slow-twitch muscle fiber identity in response to Hedgehog signaling
Baxendale, S., Davison, C., Muxworthy, C., Wolff, C., Ingham, P.W., and Roy, S.
Date: 2004
Source: Nature Genetics   36(1): 88-93 (Journal)
Registered Authors: Baxendale, Sarah, Davison, Claire, Ingham, Philip, Roy, Sudipto, Wolff, Christian
Keywords: none
MeSH Terms:
  • Animals
  • Cell Differentiation
  • DNA-Binding Proteins/physiology*
  • Hedgehog Proteins/physiology*
  • Molecular Sequence Data
  • Muscle Fibers, Slow-Twitch/physiology*
  • Nuclear Proteins
  • Repressor Proteins/physiology*
  • Signal Transduction
  • Transcription Factors/physiology*
  • Zebrafish/embryology*
  • Zebrafish Proteins/physiology*
PubMed: 14702044 Full text @ Nat. Genet.
Vertebrate skeletal muscles comprise distinct fiber types that differ in their morphology, contractile function, mitochondrial content and metabolic properties. Recent studies identified the transcriptional coactivator PGC-1alpha as a key mediator of the physiological stimuli that modulate fiber-type plasticity in postembryonic development. Although myoblasts become fated to differentiate into distinct kinds of fibers early in development, the identities of regulatory proteins that determine embryonic fiber-type specification are still obscure. Here we show that the gene u-boot (ubo), a mutation in which disrupts the induction of embryonic slow-twitch fibers, encodes the zebrafish homolog of Blimp-1, a SET domain-containing transcription factor that promotes the terminal differentiation of B lymphocytes in mammals. Expression of ubo is induced by Hedgehog (Hh) signaling in prospective slow muscle precursors, and its activity alone is sufficient to direct slow-twitch fiber-specific development by naive myoblasts. Our data provide the first molecular insight into the mechanism by which a specific group of muscle precursors is driven along a distinct pathway of fiber-type differentiation in response to positional cues in the vertebrate embryo.