Kozak M
Department of Biochemistry, University of Medicine and Dentistry of New Jersey, Piscataway 08854.
J Cell Biol. 1991 Nov;115(4):887-903. doi: 10.1083/jcb.115.4.887.
Five structural features in mRNAs have been found to contribute to the fidelity and efficiency of initiation by eukaryotic ribosomes. Scrutiny of vertebrate cDNA sequences in light of these criteria reveals a set of transcripts--encoding oncoproteins, growth factors, transcription factors, and other regulatory proteins--that seem designed to be translated poorly. Thus, throttling at the level of translation may be a critical component of gene regulation in vertebrates. An alternative interpretation is that some (perhaps many) cDNAs with encumbered 5' noncoding sequences represent mRNA precursors, which would imply extensive regulation at a posttranscriptional step that precedes translation.
已发现mRNA中的五个结构特征有助于提高真核生物核糖体起始过程的保真度和效率。根据这些标准仔细研究脊椎动物的cDNA序列会发现一组转录本——编码癌蛋白、生长因子、转录因子和其他调节蛋白——这些转录本似乎注定难以被翻译。因此，在翻译水平上进行调控可能是脊椎动物基因调控的关键组成部分。另一种解释是，一些（也许是许多）5'非编码序列有阻碍的cDNA代表mRNA前体，这意味着在翻译之前的转录后步骤存在广泛调控。
