TGFbeta3 is expressed in differentiating muscle of the embryonic mouse tongue

Abstract

The purpose of the present study was to elucidate the involvement of transforming growth factor betas (TGFβ β β β βs) in the differentiation of tongue striated muscles by analyzing the expression of TGFβ β β β βs, their receptors and factors of TGFβ β β β β signal transduction in the mouse tongue between embryonic days 11 (E11) and E15. The expression levels of TGFβ β β β β3 mRNA and protein were much higher than those of TGFβ β β β β1 and TGFβ β β β β2 , and the immunolocalization of TGFβ β β β β3 was more consistent with the differentiating muscle cells in comparison with those of TGFβ β β β β1 and 2 between E12 and E15. TGFβ β β β βRI and II were localized to the differentiating muscle cells between E11 and E15. Phosphorylated-smad2/3 was localized to the nucleus of muscle cells which just began to differentiate. These results suggest that the signal of TGFβ β β β β3, but not that of β β β β β1 or β β β β β2, may be involved in the early stages (particularly the beginning) of differentiation of mouse tongue muscle cells through TGFβ β β β βRI, TGFβ β β β βRII, and smad2/3.

Bone morphogenetic protein-2 functions as a negative regulator in the differentiation of myoblasts, but not as an inducer for the formations of cartilage and bone in mouse embryonic tongue

“…We previously reported several different functions of peptide growth factors in the development of tongue muscle cells from limb and cultured myogenic cell lines: TGFα promotes early differentiation of mouse tongue myoblasts [33-35], whereas it does not affect the differentiation of the C2C12 myoblast [36]; and the signal of TGFβ3, but not of 1 or 2, plays a role in the early stages in the differentiation of mouse tongue muscle cells through TGFβ receptor I, TGFβ receptor II, and smad2/3 [37], but TGFβ1 inhibits the differentiation of limb skeletal muscle cells [38,39]. In addition to the function of growth factors, there are several studies showing other differences between tongue muscle cells, and limb and cultured myogenic cell lines, such that fMyHC is expressed not only in the myotubes and myofibers of tongue muscles but also in the myoblasts of tongue muscles, although it is not expressed in the myoblasts of trunk and limb muscles [40].…”

The function of platelet‐derived growth factor in the differentiation of mouse tongue striated muscle

“…TGF‐α promotes early differentiation of mouse tongue myoblasts (24, 32, 33), while it does not affect the differentiation of the C2 myoblast (34). The signal of TGFβ3, not of TGFβ1 or TGFβ3, plays a role in the early stages of differentiation of mouse tongue muscle cells through TGFβRI, TGFβRII, and smad2/3 (35), but TGFβ1 inhibits the differentiation of limb skeletal muscle cells (36, 37). The present findings also support our notion that the program governing tongue myogenesis differs from those for limb and cultured myogenic cell lines.…”