Activation of the gene encoding the glycolytic enzyme β-enolase during early myogenesis precedes an increased expression during fetal muscle development

Maturation of the Myogenic Program Is Induced by Postmitotic Expression of Insulin-Like Growth Factor I

“…In MLC-IGF-I transfectants, the postmitotic expression of IGF-I induces the expression of the neonatal isoform of MyHC, normally silent in L6E9 cells (Fig. 6), up-regulation of MCK, normally silent in embryonic muscle (17), and up-regulation of ␤-enolase, normally expressed at very low levels in embryonic stages (2,27), suggesting that postmitotic IGF-I expression promotes a maturation of the myogenic program. This view is consistent with the phenotype of knockout mice nullizygous either for IGF-I or the IGF-I receptor, each of which suffer a decline in growth rate beginning at embryonic day 13.5 and exhibit marked muscle hypoplasia at birth (29,36).…”

Biochemical characterization of the mouse muscle-specific enolase: developmental changes in electrophoretic variants and selective binding to other proteins

“…Production of specific antibodies directed against the commercially available rabbit β-enolase in sheep [9] and against mouse α-and γ-enolase in rabbit [14] has been previously described. For Western blot studies, the anti-MCK serum was diluted 1\250 and the anti-α and -γ-enolase sera were diluted respectively 1\5000 and 1\1000.…”

“…These results could explain the observed striated pattern of α-and β-enolase immunoreactivity [11,18], suggesting that such associations are sufficient to localize the muscle enolase isoforms near the sarcomeric apparatus. This targeting might be modulated by the enolase isoform composition, which changes during development and with fibre type in adult muscles [9,[11][12][13].…”

“…In the mouse embryo, β-enolase transcripts are detected in cardiac tube and newly formed myotomes. The gene is further up-regulated at various stages of muscle development, and appears to be under innervational and hormonal control [9][10][11]. At the adult stage, β-enolase transcript and subunit accumulate preferentially in fasttwitch fibres of hindlimb muscles, where the ββ isoenzyme accounts for more than 90 % of total enolase activity [9,[11][12][13].…”

Characterization of porcineENO3: genomic and cDNA structure, polymorphism and expression

“…The two spliced forms are expressed during the three postnatal stages of skeletal muscle development in Yorkshire pigs and the highest levels are observed in skeletal muscle at postnatal 1 day. In mouse, [1] have shown that the level of beta enolase is increased in newborn and adult muscle, and [8] and [9] have reported that it is also increased during foetal muscle development and during terminal differentiation of myoblasts, respectively. Hence, it is possible that beta enolase plays important roles during skeletal muscle development, including muscle differentiation.…”