Polyadenylation of Chinese hamster dihydrofolate reductase genomic genes and minigenes after gene transfer.
Polyadenylation of Chinese hamster dihydrofolate reductase genomic genes and minigenes after gene transfer.
复制标题
基因转移后中国仓鼠二氢叶酸还原酶基因组基因和小基因的多聚腺苷酸化。
DOI：
10.1007/bf01534491
复制
发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Chasin,LA
中科院分区：
文献类型：
--
作者：
Venolia,L;Urlaub,G;Chasin,LA
The major alternative polyadenylation sites in the Chinese hamster dihydrofolate reductase(dhfr)gene have been identified by DNA sequencing and RNase protection experiments. Comparison of the 3′ gene sequence and polyadenylation sites with those of the mouse reveals that, despite an overall sequence homology, the major sites are different in the two species. A series of minigenes was constructed containing thedhfrpromoter and the first intron but lacking the four large introns of the genomic sequence. These minigenes contained either all three polyadenylation sites, no polyadenylation sites, or just the first site. All of these minigenes, as well as a cosmid clone containing the full genomic sequence, could transform DHFR-deficient Chinese hamster ovary cell mutants to a DHFR-positive phenotype with approximately equal efficiencies. A minigene lacking the first intron was markedly less efficient. Analysis ofdhfrmRNA from transfectant clones derived from minigenes showed that thedhfrpolyadenylation sites were used when included, but novel sites were often used in addition. When endogenous polyadenylation sites were absent, new sites in flanking carrier or host DNA were recruited. Transfectants produced by the full genomicdhfrgene yielded mRNA species that were identical in size and relative abundance to the endogenousdhfrgene. The results indicate that the minimal signals for polyadenylation are not complex and can be easily acquired from foreign sequences.
