High efficiency gene transfer and expression in mammalian cells by a multiple transfection procedure of matrix attachment region sequences

摘要

A purified and isolated DNA sequence has protein production increasing activity. Said DNA sequence comprises at least one bent DNA element, and at least one binding site for a DNA binding protein. It is a MAR nucleotide with the sequence SEQ ID No 26, a sequence complementary thereof, or a sequence having at least 70% identity with said sequence. Advantageously the bent DNA element contains at least 10% of dinucleotide TA, and/or at least 12% of dinucleotide AT on a stretch of 100 contiguous base pairs.