High impact information on MYF5

• Delta 1-activated notch inhibits muscle differentiation without affecting Myf5 and Pax3 expression in chick limb myogenesis [1].
• We conclude that activation of Notch signalling during chick limb myogenesis prevents Myf5-expressing myoblasts from progressing to the MyoD-expressing stage [1].
• These data indicate that Myf5 and MyoD are involved in different steps during chick limb bud myogenesis, Myf5 acting upstream of MyoD [1].
• A survey of the expression of myogenic genes showed that the myogenic markers Myf5, MyoD and myogenin were expressed in branchial arch muscle, but at comparatively late stages compared with their expression in the somites [2].
• In this study, we have isolated and characterized the chicken Myf5 gene, and cDNA clones encoding chicken MyoD1 and myogenin [3].

Biological context of MYF5

• The chicken Myf5 and MRF4 genes are tandemly located on a single genomic DNA fragment, and the chicken Myf5 gene is organized into at least three exons [3].
• Myogenin gene activity declined rapidly (t1/2: approximately 2 min), comparable to the rate of acetylcholine receptor (AChR) gene inactivation, while other myogenic bHLH genes either lost activity more slowly (MyoD) or not at all (myf5, herculin) [4].
• We show that treatment with activin resulted in a downregulation of Pax-3 and MyoD expression within 6 h after treatment, whereas expression of Myf-5 and Pax-7 was largely unaffected [5].

Anatomical context of MYF5

• After activation of this pathway, myoblasts still express Myf5 and Pax3 but have downregulated MyoD, resulting in inhibition of terminal muscle differentiation [1].
• Chordin diverted somatic muscle cells to more anterior positions within the somite file in chordin-induced secondary trunks and induced the expression of the anterior myogenic gene myf5 [6].

Associations of MYF5 with chemical compounds

• Messages coding for MyoD, myf5, and herculin decay much more slowly, as a result of slower turnover [7].

Regulatory relationships of MYF5

• We used these data to generate a schematic composite of expression patterns at the level of the segmental plate and developing somites (stage V) that shows multiple Frizzled and Wnt transcripts expressed in tissues that are overlapping and adjacent to Myf-5 and MyoD expressing tissues [8].

Other interactions of MYF5

• Thus, we sought to determine which Wnts and Frizzled exhibit expression patterns that are spatiotemporally consistent with the expression of two myogenic determination factors: Myf-5 and MyoD [8].

Analytical, diagnostic and therapeutic context of MYF5

• 2. Upon denervation, herculin mRNA remains essentially unchanged, myf5 transcript levels approximately double, and MyoD message is up-regulated by two- to fivefold [7].
• 1. We have prepared probes specific for the chicken myogenic determination genes MyoD, myogenin, myf5, and herculin and have investigated the expression of these genes in response to denervation and acute electrical stimulation in neonate chick muscle, using ribonuclease protection [7].

References