3 results about "Protein expression" patented technology

The invention relates to the technical field of biology, in particular to application of ICOSL (Inducible Costimulator Ligand) protein in preparation of a kit used for breast cancer prognosis evaluation. According to the invention, the immunohistochemistry technology and a semi-quantitative analysis method of a staining result are employed to analyze the expression level of the ICOSL protein in atumor tissue, and combine with post-operative follow-up information to determine whether the ICOSL protein expression has correlation with the prognosis of a breast cancer patient or not, wherein theICOSL protein can be used for preparing a protein molecular marker for determining the prognosis of the breast cancer patient to have important guiding significance for post-operative monitoring and sequential treatment of the breast cancer patients.

The invention belongs to the technical field of biological preparation and in particular relates to an RXRalpha (Homo Sapiens Retinoid X Receptor alpha) gene knockout cell system with stable and low expression of an RXRalpha protein and a preparation method of the RXRalpha gene knockout cell system. The cell system is an RXRalpha gene knockout cell system; the knockout base number is an integral multiple of a number except 3; RXRalpha protein expression in a cell is remarkably reduced, the genotype is stable and can be passed to next generations, the stability of the RXRalpha low-expression cell system is greatly improved, and stable generation passage and continuous culture of the cell system can be facilitated. The invention provides the preparation method of the cell system. The preparation method comprises the following steps: according to RXRalpha gene sequence information, designing a CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) knockout gRNA (Guide Ribonucleic Acid) sequence, establishing a gRNA expression vector, and carrying out in-vitro cell level detection on gRNA shearing activity; by using a nuclear transferring method, carrying out cotransfectionon an immortalized cell of human neuroblastoma, that is, an SK-N-SH cell, by using cas9 and the gRNA expression vector, carrying out G418 medicine screening so as to obtain stable cell cloning, carrying out a PCR (Polymerase Chain Reaction) and gene sequencing to identify that the cell is cell cloning of which the RXRalpha gene is knocked out for an integral multiple of a number except 3, therebyobtaining the RXRalpha gene knockout cell system with stable and low expression of the RXRalpha protein.