Method for altering the expression of a target sequence of endogenous nucleic acid in a target cell, cdna transcription and target cell

摘要

"METHOD TO CHANGE THE EXPRESSION OF A TARGET ENDOGENIC NUCLEIC ACID SEQUENCE IN A TARGET CELL, CDNA TRANSCRIPTION AND TARGET CELL". The present invention relates to methods for altering the expression of a target nucleic acid sequence in a target cell by producing single strand cDNA (ss-cDNA) in the target cell in vivo. The target cell is transfected with a cassette comprising a sequence of interest, an inverted conjugate repeat and a 3 'primer binding site (PBS) for the inverted conjugate repeat. Transcription of the cassette by the target cell produces an RNA template which is reverse transcribed to produce ss-cDNA of a specific sequence. The reverse transcriptase / RNase encoding gene can also be transfected into the target cell. The ss-cDNA is modified to remove all flanking vectors by taking advantage of the ss-cDNA link structure, which is formed as a result of the inverted conjugate repetition that allows the ss-cDNA to fold over itself, forming a double stranded DNA strand. The double strand chain contains one or more restriction sites for endonuclease recognition and the link, which remains as ssDNA, is comprised of the sequence of interest, which can be any desired nucleotide sequence. This design allows the double strand chain of the intermediate chain link to be cleaved by the desired corresponding endonuclease restriction (s) and the link portion of the sequence of interest is then released as a piece of DNA. single, linearized cord. This piece of ssDNA released (or cleaved) contains minimum sequence information, if any, either upstream 5 'or downstream 3' from the double strand chain. The resulting ssDNA binds to a target sequence of endogenous nucleic acid to alter the expression of that sequence for therapeutic purposes such as deactivating a gene using a double or triple bond of site-directed mutagenesis nucleic acids, disrupting cell function by binding specific cell proteins, and interfere with RNA-splitting functions.