| First Author | Kablar B | Year | 1999 |
| Journal | Dev Biol | Volume | 206 |
| Issue | 2 | Pages | 219-31 |
| PubMed ID | 9986734 | Mgi Jnum | J:53111 |
| Mgi Id | MGI:1331296 | Doi | 10.1006/dbio.1998.9126 |
| Citation | Kablar B, et al. (1999) Myogenic determination occurs independently in somites and limb buds. Dev Biol 206(2):219-31 |
| abstractText | Gene targeting has indicated that the bHLH transcription factors Myf-5 and MyoD are required for myogenic determination because skeletal myoblasts and myofibers are entirely ablated in mouse embryos lacking both Myf-5 and MyoD. Entrance into the skeletal myogenic program during development occurs following the independent transcriptional induction of either Myf-5 or MyoD. To identify sequences required for the de novo induction of MyoD transcription during development, we investigated the expression patterns of MyoD-lacZ transgenes in embryos deficient in both Myf-5 and MyoD. We observed that a 258-bp fragment containing the core of the -20-kb MyoD enhancer activated expression in newly formed somites and limb buds in compound mutant embryos lacking both Myf-5 and MyoD. Importantly, Myf-5- and MyoD-deficient presumptive muscle precursor cells expressing beta-galactosidase were observed to assume nonmuscle fates primarily as precartilage primordia in the trunk and the limbs, suggesting that these cells were multipotential. Therefore, cells are recruited into the MyoD-dependent myogenic lineage through activation of the -20-kb MyoD enhancer and this occurs independently in somites and limb buds. Copyright 1999 Academic Press. |
