Fully automated two-dimensional electrophoresis system for high-throughput protein analysis.

We developed a fully automated electrophoresis system for rapid and highly reproducible protein analysis. All the two-dimensional (2D) electrophoresis procedures including isoelectric focusing (IEF), on-part protein staining, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and in situ protein detection were automatically completed. The system comprised Peltiert devices, high-voltage generating devices, electrodes, and three disposable polymethylmethacrylate (PMMA) parts for IEF, reaction chambers, and SDS-PAGE.

Transforming growth factor betas are upregulated in the rat masseter muscle hypertrophied by clenbuterol, a beta2 adrenergic agonist.

1. The regulatory mechanism for the hypertrophy of skeletal muscles induced by clenbuterol is unclear. The purpose of the present study was to determine the extent to which transforming growth factor betas (TGFbetas), fibroblast growth factors (FGFs), hepatocyte growth factor (HGF), and platelet-derived growth factors (PDGFs) are involved in the hypertrophy of rat masseter muscle induced by clenbuterol.

Satellite cells and utrophin are not directly correlated with the degree of skeletal muscle damage in mdx mice.

To determine whether muscle satellite cells and utrophin are correlated with the degree of damage in mdx skeletal muscles, we measured the area of the degenerative region as an indicator of myofiber degeneration in the masseter, gastrocnemius, soleus, and diaphragm muscles of mdx mice. Furthermore, we analyzed the expression levels of the paired box homeotic gene 7 (pax7), m-cadherin (the makers of muscle satellite cells), and utrophin mRNA. We also investigated the immunolocalization of m-cadherin and utrophin proteins in the muscles of normal C57BL/10J (B10) and mdx mice.

Exogenous hepatocyte growth factor inhibits myoblast differentiation by inducing myf5 expression and suppressing myoD expression in an organ culture system of embryonic mouse tongue.

We examined the effects of exogenous hepatocyte growth factor (HGF) on the differentiation and proliferation of tongue myoblasts by using an organ culture system of tongue obtained from mouse embryos at embryonic day (E) 13. Exogenous HGF induced reductions in the quantities of muscle creatine kinase and myogenin mRNAs and in the number of fast myosin heavy chain-positive myoblasts and myotubes, suggesting that HGF suppressed the differentiation of myoblasts in the cultured E13 tongues. Exogenous HGF induced no significant changes in the percentage of proliferating cell nuclear antigen (PCNA)-positive cell nuclei to total cell nuclei (labeling index) in the muscle portion of the cultured E13 tongue, suggesting that HGF did not affect the proliferation of myoblasts.

Change from a hard to soft diet alters the expression of insulin-like growth factors, their receptors, and binding proteins in association with atrophy in adult mouse masseter muscle.

To study the role of insulin-like growth factors (IGFs) in the atrophy of mouse masseter muscle in response to a change from a hard to a soft diet, we analyzed the amounts of mRNA and the immunolocalization for IGF-I, IGF-II, their receptors (IGFRs), and binding proteins (IGFBPs). Sixteen male ICR mice were fed a hard diet after weaning; they were divided into two groups at 6 months of age and fed a hard or a soft diet for 1 week. The soft diet treatment decreased masseter weight by 19% ( P<0.

Changes in the mRNA expressions of insulin-like growth factors, their receptors, and binding proteins during the postnatal development of rat masseter muscle.

Morphological, biochemical, and functional changes in rat masseter muscle reportedly occur during the shift of rat feeding behavior from suckling to chewing. To determine whether insulin-like growth factors (IGFs), their receptors (IGFRs), and binding proteins (IGFBPs) are involved in the changes in rat masseter muscle during the shift of rat feeding behavior, we analyzed the expressions of IGF-I, IGF-II, IGFR1, IGFR2, and IGFBP1~6 mRNAs in rat masseter muscle between 0 and 70 days after birth using the competitive, reverse transcriptase-polymerase chain reaction (RT-PCR) method. Between 14 and 19 days of age, sharp falls in the quantities of IGF-I, IGF-II, IGFR1, IGFR2, IGFBP3, IGFBP5, and IGFBP6 mRNAs were observed, whereas the quantity of IGFBP4 mRNA rose sharply during the same period.

Biochemical and immunohistochemical studies on tropomyosin and glutamate dehydrogenase in the chicken liver.

Recently, we have reported a novel tropomyosin (TM) -binding protein, glutamate dehydrogenase (GDH) and demonstrated by affinity column chromatography that chicken liver TM interacts with GDH in an ATP-dependent manner. To elucidate the physiological roles of the interaction between TM and GDH, we performed co-sedimentation assays of TM and GDH with F-actin, because it is known that TM exerts its physiological functions by associating with actin filaments. The results showed that TM and GDH co-pelleted with F-actin.

Developmental changes of cardiac and slow skeletal muscle troponin T expression in chicken cardiac and skeletal muscles.

Numerous troponin T (TnT) isoforms are produced by alternative splicing from three genes characteristic of cardiac, fast skeletal, and slow skeletal muscles. Apart from the developmental transition of fast skeletal muscle TnT isoforms, switching of TnT expression during muscle development is poorly understood. In this study, we investigated precisely and comprehensively developmental changes in chicken cardiac and slow skeletal muscle TnT isoforms by two-dimensional gel electrophoresis and immunoblotting with specific antisera.