van Hoof A, Green P J
MSU-DOE Plant Research Laboratory, East Lansing 48824-1312, USA.
Plant Mol Biol. 1997 Oct;35(3):383-7. doi: 10.1023/a:1005849622840.
In plants, as in other eukaryotes, most synonymous codons of the genetic-code are not used with equal frequency, but instead some codons are preferred, whereas others are rare. Circumstantial evidence led to the suggestion that rare codons have a negative influence on mRNA stability. To address this question experimentally, rare codons encoded by a Bacillus thuringiensis (B.t.) toxin gene (cryIA(c)) or a synthetic sequence were introduced into a phytohemagglutinin (PHA) reporter gene. In neither case was the mRNA stability appreciably diminished in stably transformed tobacco cell cultures nor was the accumulation of mRNA in transgenic plants affected. Thus rare codons do not appear to be sufficient to cause rapid degradation of the PHA mRNA and potentially other mRNAs in plants.
与其他真核生物一样，在植物中，遗传密码的大多数同义密码子并非以相同频率使用，而是有些密码子受到偏爱，而有些则很少使用。间接证据表明，稀有密码子对mRNA稳定性有负面影响。为了通过实验解决这个问题，将苏云金芽孢杆菌（B.t.）毒素基因（cryIA(c)）编码的稀有密码子或合成序列引入到植物血凝素（PHA）报告基因中。在稳定转化的烟草细胞培养物中，这两种情况下mRNA稳定性均未明显降低，转基因植物中mRNA的积累也未受影响。因此，稀有密码子似乎不足以导致植物中PHA mRNA以及可能的其他mRNA的快速降解。
