Expression of Nuclear Lamin A and Muscle-Specific Proteins in Differentiating Muscle Cells in Ovo and in vitro

• Published in: The Journal of cell biology 1989-08, Vol.109 (2), p.495-504
• Main Authors: Lourim, David, Lin, Jim Jung-Ching
• Format: Article
• Language: English
• Subjects: Animals; Antibodies; Biological and medical sciences; Cell culture techniques; Cell Differentiation; Cell nucleus; Cells; Chick Embryo; Cultured cells; Embryonic cells; Fluorescent Antibody Technique; Fundamental and applied biological sciences. Psychology; Gels; Gene expression; Immunoblotting; Lamin Type A; Lamins; Molecular and cellular biology; Molecular genetics; Muscle Proteins - genetics; Muscles - cytology; Muscles - metabolism; Myoblasts; Myosins - genetics; Myosins - metabolism; Nuclear Proteins - genetics; Nuclear Proteins - metabolism; Precipitin Tests; Protein isoforms; skeletal muscle; Tropomyosin - genetics; Tropomyosin - metabolism
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.109.2.495

Primary cultures and tissue samples of chicken embryonic muscle were immunologically probed for the expression of muscle-specific proteins, such as myosin heavy chain and the tropomyosins, as well as for the nuclear lamina protein, lamin A. As determined by quantitative immunoblotting, the expression of lamin A and the muscle-specific proteins were at low levels or absent in predifferentiation myoblasts both in vitro and in ovo. During differentiation, an increase of lamin A expression preceded the induction to high levels of expression of muscle-specific proteins. Immunofluorescence staining of chicken embryonic muscle cells in culture also indicates an accumulation of lamin A before the induction of muscle-specific proteins expression. Furthermore, the accumulation of lamin A reached a plateau before the muscle-specific proteins during muscle development. In two dimensional NEPHGE gel analysis of immunoprecipitated lamin A, no detectable change in the ratio of the acidic/basic isoelectric variants of lamin A was observed during myogenesis. A potential role for lamin A in the mechanisms which underlie the differential and coordinate expression of muscle-specific genes is proposed.