Biomedical subjects

Yong-Fu Chen

Publications and source records attributed to Yong-Fu Chen.

8 recordsLinked to original sources

PubMed2006

Expression of basic fibroblast growth factor results in the decrease of myostatin mRNA in murine C2C12 myoblasts.

During the development and regeneration of skeletal muscle, many growth factors, such as basic fibroblast growth factor (bFGF, FGF-2) and myostatin, have been shown to play regulating roles. bFGF contributes to promote proliferation and to inhibit differentiation of skeletal muscle, whereas myostatin plays a series of contrasting roles. In order to elucidate whether the expression of bFGF has any relationship with the expression of myostatin in skeletal muscle cells, we constructed a eukaryotic expression vector for the expression of exogenous bFGF in murine C2C12 myoblasts. Quantitative RT-PCR assays indicated that with the increase of the expression of exogenous bFGF gene, the expression of endogenous myostatin gene was suppressed at mRNA level and protein level.

Animals↗

PubMed2006

[Porcine follistatin cDNA cloning and expression in Escherichia coli].

The total RNA was extracted from porcine ovary. Porcine Follistatin cDNA was cloned by RT-PCR. Complete porcine follistatin cDNA coding sequences are presented including 1038 bp of open reading frame. The purified porcine follistatin cDNA was inserted into pGEX-4T-3 vector to construct the prokaryotic fusion protein expression vector. The recombinant expression plasmid was transformed into BL21 (DE3) and expression was induced by IPTG. Protein products were detected by SDS-PAGE and confirmed by Western blotting analysis, which showed that the yield of the Follistatin cDNA was a 63kD protein expression vector. Follistatin protein was expressed in the form of glutathione-S-transferase (GST) fusion protein in E. coli.

Amino Acid Sequence↗

PubMed2005

Cloning and sequence analysis of myostatin promoter in sheep.

To better understand the structure and function of the myostatin's gene promoter region in sheep, we cloned and sequenced a 1.517 kb fragment containing the 5'-regulatory region of the sheep myostatin gene (GenBank accession number is AY918121). The promoter sequence consists of three TATA boxes, one CAAT box, and eight putative E-boxes. Some putative muscle growth response elements for Octamer-binding factor 1(Octamer), Activator protein 1(AP1), Growth factor independence 1 zinc finger protein (Gfi-1B), Myocyte enhancer factor 2 (MEF2), Muscle-specific Mt binding site (MTBF), Glucocorticoid response elements (GRE) and Progesterone receptor binding site (PRE) were detected. Some of the motifs are conserved as compared to with that in the goat, bovine and porcine myostatin promoters. However, some differences were also found.

Animals↗

PubMed2005

[Normal mice derived from oocytes following intracytoplasmic sperm injection (ICSI)].

This paper describes the use of piezo-driven micropipette for intracytoplasmic sperm injection of mice eggs. The head of fresh spermatozoa from KM (Kunming) fertile mice was individually injected into mature oocytes of hybrid mice B6D2F1. Approximately eighty three percent of sperm-injected oocytes survived, and 84.0% of them fertilized normally (extrusion of the second polar body and formation of male and female pronuclei). The eggs fertilized by sperm injection could develop in vitro to 2-cell (98% vs 94.7%), 4-cell (89.5% vs 92.1%) stages, no significantly (P > 0.05) different from embryos fertilized in vivo but there were significantly (P < 0.01) few morulae (63.8% vs 84.2%) and blastocysts (25.7% vs 68.4%) developed in vitro after further culture in vitro in the group of ICSI. When 120 embryos at the pronuclear stage were transferred to seven pseudopregnant KM female, 23.3% of the embryos (0 - 50%, depending on the host) reached the full term. Except for three that were cannibalized soon after birth, all of the young (25 pups) developed into normal and fertile adult. Here we report the first birth of mouse offspring following ICSI in China. These studies may increase understanding of the fertilization process and of how ICSI works.

Animals↗

PubMed2005

[Secreted expression of porcine interferon-gamma gene in Pichia pastoris].

The porcine interferon-gamma (PoIFN-gamma) gene, in which the sequence encoding signal peptide was replaced by that of the alpha-factor of Saccharomyces cerevisiae, was cloned into Pichia pastoris expression vector pPIC9K. The recombinant plasmid pPIC9K-alpha-PoIFN-gamma was then transformed into Pichia pastoris GS115 cells by electroporation and stable multicopy recombinant Pichia pastoris strains were selected by G418 resistance. Two recombinants of multiple inserts were obtained. SDS-PAGE and Western blot assays of culture broth from a methanol-induced expression strain demonstrated that recombinant PoIFN-gamma, 17kD and 23kD proteins, were secreted into the culture medium. Target proteins, 60% of total proteins, were obtained in the culture medium at the concentration of 108 mg/L. This is the first secreted expression of porcine interferon-gamma gene in Pichia pastoris.

Animals↗

PubMed2005

[Study on effect of Lactobacillus acidophilus MG2-1 on serum lipid metabolism in rats].

Wistar rats were fed with a high lipid diet supplemented with living or thermal death bacteria of Lactobacillus acidophilus MG2-1 which was isolated from koumiss in Mongolia and was of good ability of acid tolerance and decreasing the level of cholesterol in vitro. The effect of Lb. acidophilus MG2-1 on the metabolism of serum cholesterol was discussed. It was showed that it was on the 14th day of experiment that the inhibiting effects of the increase of serum cholesterol level of rat groups fed with living bacteria and heat-killed bacteria was significantly (p > 0.05) and very significantly (p < 0.01) higher than that of the high lipid diet group respectively; at the same time, the level of serum HDL-C of the thermal death bacteria group was significantly higher than that of the high lipid diet group (p < 0.05), also arteriosclerosis index of wistar rats in experimental group is significantly lower than that of the high lipid diet group (p < 0.01). The total bile acid level of the thermal death bacteria group in fecal is significantly higher than that of the high lipid diet group (p < 0.05). It is suggested that the increase of serum cholesterol level in rats can be inhibited and arteriosclerosis can also be prevented by this strain. During the period of tests, the effect of the strain on serum lipid in rats weaken with the time going, while the dose of bacteria fed was not changed.

Animals↗

PubMed2003

[Molecular cloning, expression mutation of myostatin and study on biochemical activity of its C-terminal peptide].

Myostatin, a member of the TGF-beta family, negatively regulates skeletal muscle development. Mutation of myostatin activity leads to increases muscle growth and carcass lean yield. The bovine myostatin mutation cDNA was amplified by polymerase chain reaction, and then sub-cloned into the expression vector pET-30a( + ) to form the expression plasmid pET30a (+)-action/ Myostatin. The recombinant plasmid was transformed into E. coli BL21. The overexpression product of pET30a (+)-action/ Myostatin was been showed in vitro. Sheep skeletal muscle cell were cultured with the purified myostatin mutation C-terminal peptide. The results of this study suggest that had a powerful activity to stimulate the hyperplasia and proliferation of sheep muscle cells and shows high biochemical activity.

Animals↗

PubMed2002

[Transgenic animals bioreactors].

The production of human recombinant proteins in milk of transgenic farm animals offers a safe, very cost-effective source of commercially important proteins that cannot be produced as efficiently in adequate quantities by other methods. This review has summarized the current status of gene selection, vector construct, transgenic methods, economics, and obvious potential in transgenic animals bioreactors. Recently, a more powerful approach was adopted in the transgenic animals founded on the application of nuclear transfer. As we will illustrate, this strategy presents a breakthrough in the overall efficiency of generating transgenic farm animals, product consistency, and time of product development. The successful adaptation of Cre-/lox P-mediated site-specific DNA recombination systems in farm animals will offer unprecedented possibilities for generating transgenic animals.

Animals↗