BACKGROUNDTo study the effect of gene amplification and selection system with DHFR plus GS and DHFR or GS gene on the foreign gene expression.

METHODSUsing the N-terminal truncated hTPO(T184) gene as target gene, two plasmidsre were constructed: pDC- T184 and pGC-T184 where DHFR and GS gene were used respectively as the selective amplification marker. They were cotransfected into CHO dhfr cells to establish dual gene amplification and selection system of DHFR plus GS gen and respectively transfected to establish single gene amplification and selection system of DHFR or GS gene. Three selective methods in dual selective system to compare expression efficiency of hTPO were designed: the first method (DG) was to use drug pressure of MTX, then use MSX; the second method (GD) was reversed; the third method was simultaneously to use MTX and MSX as drug pressure.

RESULTSDHFR+GS dual system had not only higher gene amplification efficiency but also higher level expression. There was no distinct affect in different method of drug pressure.

CONCLUSIONSMTX plus MSX dual drug pressure in dual selection system was an efficient and simple method to increase the expression of foreign gene in mammalian cells.

Animals ; CHO Cells ; Cricetinae ; Gene Amplification ; drug effects ; Gene Expression ; Glutamate-Ammonia Ligase ; genetics ; Methotrexate ; pharmacology ; Plasmids ; genetics ; Tetrahydrofolate Dehydrogenase ; genetics

Objective This study aims to discuss the research hotspot and development trend in the field of polycystic ovary syndrome(PCOS)through bibliometric statistics and visual analysis of long noncoding RNA(lncRNA)related studies.Methods Utilizing the Web of Science core database as the literature data source,we searched for PCOS lncRNA-related literature from 2015 to 2023.CiteSpace software was used to conduct a visual analysis,including the annual distribution,citation trends,countries,institutions,funding sources and key words,as well as co-occurrence and cluster analysis of key words.Results The visual analysis of 108 PCOS lncRNA literature revealed that China was the country with the highest number of publications.The first contributing institution was the Shandong University.The national natural science fund of China gave the biggest funding.The keyword cluster analysis suggested that PCOS lncRNA signal pathway regulation,related receptor activators,and the expression of regulatory factors were the research hotspots in ovary syndrome lncRNA research.Conclusion LncRNA related regulatory factors,bioinformatics analysis,and gene transcription in PCOS are new targetsfor PCOS treatment,providing valuable insights for clinical therapy and new strategies for the development of PCOS-related pharmaceuticals.