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1951年Watson和Crick提出的模型指出遗传信息(基因)储存于DNA中,当基因被表达时,DNA首先转录成互补于一条DNA链的mRNA,再按三个核苷酸为一组的密码子译码为蛋白质。现在我们不谈染色体中编码蛋白质的DNA顺序,而讨论不编码蛋白质的那些DNA顺序,它们表现为具有调控功能的DNA,在基因表达中起调控作用。细菌基因表达的简单模型在细菌细胞中,DNA由RNA聚合酶转录成RNA,当RNA仍联在RNA聚合酶上时,核糖体就结合上去,蛋白质也就合成
The model proposed by Watson and Crick in 1951 states that genetic information (genes) is stored in DNA. When a gene is expressed, it is first transcribed into mRNA that is complementary to a strand of DNA, followed by a three-nucleotide set of codons Decoding to protein. Now that we talk about the DNA sequences that encode proteins in chromosomes, we talk about those DNA sequences that do not encode proteins. They behave as regulatory DNA and play a regulatory role in gene expression. A Simple Model of Bacterial Gene Expression In bacterial cells, DNA is transcribed into RNA by RNA polymerase. When RNA is still linked to RNA polymerase, the ribosome binds and the protein is synthesized