CHLOROPLAST DNA CODON USE - EVIDENCE FOR SELECTION AT THE PSB-A LOCUS BASED ON TRANSFER-RNA AVAILABILITY
CHLOROPLAST DNA CODON USE - EVIDENCE FOR SELECTION AT THE PSB-A LOCUS BASED ON TRANSFER-RNA AVAILABILITY
复制标题
DOI：
10.1007/bf00175504
复制
发表时间：
1993-09-01
影响因子：
3.9
通讯作者：
MORTON, BR
中科院分区：
文献类型：
--
作者：
MORTON, BR
Codon use in the three sequenced chloroplast genomes (Marchantia, Oryza, and Nicotiana) is examined. The chloroplast has a bias in that codons NNA and NNT are favored over synonymous NNC and NNG codons. This appears to be a consequence of an overall high A + T content of the genome. This pattern of codon use is not followed by the psb A gene of all three genomes and other psb A sequences examined. In this gene, the codon use favors NNC over NNT for twofold degenerate amino acids. In each case the only tRNA coded by the genome is complementary to the NNC codon. This codon use is similar to the codon use by chloroplast genes examined from Chlamydomonas reinhardtii. Since psb A is the major translation product of the chloroplast, this suggests that selection is acting on the codon use of this gene to adapt codons to tRNA availability, as previously suggested for unicellular organisms.
