RESUMO
In order to construct a pichia pastoris expression vector containing the extracellular domain of human Jagged1 and the Fc fragment of human IgG1 fusion gene, or containing only the Fc fragment of human IgG1 and to express them in pichia pastoris. The extracellular domain of human Jagged1 gene was cloned from normal human bone marrow cells. After DNA sequencing, the extracellular domain of Jagged1 gene was inserted into pIC-Fc vector constructed previously, which is Pichia pastoris expression vector containing only the Fc fragment of human IgG1. The constructed plasmid was transformed into yeast GS115 by means of electroporation. The recombinant transformants with a high copy number of the plasmid were selected on MD plate with G418. The expression of protein was induced by addition of methanol. Then, protein expression was analyzed by SDS-PAGE. The results indicated that the extracellular domain of human Jagged1 gene was effectively amplified. The DNA sequencing result showed that the constructed plasmid containing hJagged1(ext)-Fc fusion gene was the same as designed. The fusion protein was successfully expressed in Pichia pastoris. It is concluded that the hJagged1(ext) gene has been successfully cloned and expressed, which provides a new fusion protein for further experiments, the hJagged1(ext)-Fc fusion protein can be used as a new stimulator for proliferation of hematopoietic stem/progenitor cells in vitro.
Assuntos
Humanos , Proteínas de Ligação ao Cálcio , Genética , Vetores Genéticos , Genética , Fragmentos Fc das Imunoglobulinas , Genética , Imunoglobulina G , Genética , Peptídeos e Proteínas de Sinalização Intercelular , Genética , Proteína Jagged-1 , Proteínas de Membrana , Genética , Pichia , Genética , Metabolismo , Proteínas Recombinantes de Fusão , Genética , Proteínas Serrate-Jagged , TransfecçãoRESUMO
Ex vivo expansion of hematopoietic progenitor cells (HPCs) is valuable for clinical application, however, traditional ex vivo culture negatively affects long-term hematopoietic reconstitution ability. In the hematopoietic system, the expression of Notch receptors and their ligands has been widely reported. Active Notch signal inhibits the differentiation of HSCs while promotes their expansion, suggesting that ex vivo expansion of hematopoietic progenitor cells could be enhanced by manipulating Notch signal pathways. In this article the Notch signal pathways, Notch signal and maintenance of hematopoietic progenitor cells, Notch signal and expansion of hematopoietic progenitor cells and molecular mechanism of Notch signal maintaining undifferentiation of hematopoietic progenitor cells were reviewed.