The muscle regulatory gene, Myf-6, has a biphasic pattern of expression during early mouse development.
The spatial and temporal expression pattern of the muscle regulatory gene Myf-6 (MRF4/herculin) has been investigated by in situ hybridization during embryonic and fetal mouse development. Here, we report that the Myf-6 gene shows a biphasic pattern of expression. Myf-6 transcripts are first detected in the most rostral somites of the mouse embryo at 9 d of gestation and accumulate progressively in myotomal cells along the rostro-caudal axis. This expression is transient and Myf-6 mRNA can no longer be detected in myotomal cells after day 12 post coitum (p.c.). In contrast to other muscle determination genes (MyoD1, myogenin, Myf-5), Myf-6 mRNA is not detected in limb buds or visceral arches and skeletal muscle of the mouse embryo (day 8-15 p.c.). In fetal mice, Myf-6 transcripts appear at day 16 p.c. in all skeletal muscles, and the gene continues to be expressed at a high level after birth. These results suggest that early Myf-6 expression may be restricted to a population of myogenic cells that does not contribute to the embryonic muscle masses in limb buds and visceral arches. The reappearance of Myf-6 mRNA in fetal skeletal muscle coincides approximately with secondary muscle fiber formation and the onset of innervation.
Bober
E
E
Department of Toxicology, Medical School, University of Hamburg, Germany.
Lyons
G E
GE
Braun
T
T
Cossu
G
G
Buckingham
M
M
Arnold
H H
HH
D001483:Base Sequence; D015152:Blotting, Northern; D004247:DNA; D005786:Gene Expression Regulation; D005809:Genes, Regulator; D006801:Humans; D008969:Molecular Sequence Data; D024510:Muscle Development; D009124:Muscle Proteins / Q000235:genetics*; D009132:Muscles / Q000196:embryology / Q000378:metabolism*; D018006:Myogenic Regulatory Factors; D018008:Myogenin; D009693:Nucleic Acid Hybridization
C503799:MYOG protein, human; D009124:Muscle Proteins; C503801:Myog protein, mouse; D018006:Myogenic Regulatory Factors; D018008:Myogenin; C063403:myogenic factor 6; D004247:DNA