Steane Dorothy A
Cooperative Research Centre for Sustainable Production Forestry, School of Plant Science, University of Tasmania, Hobart, Tasmania, Australia.
DNA Res. 2005;12(3):215-20. doi: 10.1093/dnares/dsi006.
The complete nucleotide sequence of the chloroplast genome of the hardwood species Eucalyptus globulus is presented and compared with chloroplast genomes of tree and non-tree angiosperms and two softwood tree species. The 160,286 bp genome is similar in gene order to that of Nicotiana, with an inverted repeat (IR) (26,393 bp) separated by a large single copy (LSC) region of 89,012 bp and a small single copy region of 18,488 bp. There are 128 genes (112 individual gene species and 16 genes duplicated in the inverted repeat) coding for 30 transfer RNAs, 4 ribosomal RNAs and 78 proteins. One pseudogene (psi-infA) and one pseudo-ycf (psi-ycf15) were identified. The chloroplast genome of E. globulus is essentially co-linear with that of another hardwood tree species, Populus trichocarpa, except that the latter lacks rps16 and rpl32, and the IR has expanded in Populus to include rps19 (part of the LSC in E. globulus). Since the chloroplast genome of E. globulus is not significantly different from other tree and non-tree angiosperm taxa, a comparison of hardwood and softwood chloroplasts becomes, in essence, a comparison of angiosperm and gymnosperm chloroplasts. When compared with E. globulus, Pinus chloroplasts have a very small IR, two extra tRNAs and four additional photosynthetic genes, lack any functional ndh genes and have a significantly different genome arrangement. There does not appear to be any correlation between plant habit and chloroplast genome composition and arrangement.
本文公布了阔叶树种蓝桉叶绿体基因组的完整核苷酸序列，并将其与树木和非树木被子植物以及两种针叶树种的叶绿体基因组进行了比较。该基因组大小为160,286 bp，基因顺序与烟草相似，有一个26,393 bp的反向重复序列（IR），被一个89,012 bp的大单拷贝（LSC）区域和一个18,488 bp的小单拷贝区域隔开。共有128个基因（112个独立基因种类和16个在反向重复序列中重复的基因），编码30种转移RNA、4种核糖体RNA和78种蛋白质。鉴定出一个假基因（psi-infA）和一个假ycf基因（psi-ycf15）。蓝桉的叶绿体基因组与另一种阔叶树种毛果杨的叶绿体基因组基本共线性，只是后者缺少rps16和rpl32，并且毛果杨的IR已经扩展到包括rps19（在蓝桉中是LSC的一部分）。由于蓝桉的叶绿体基因组与其他树木和非树木被子植物类群没有显著差异，因此阔叶树和针叶树叶绿体的比较本质上就变成了被子植物和裸子植物叶绿体的比较。与蓝桉相比，松树的叶绿体有一个非常小的IR、两个额外的tRNA和四个额外的光合基因，缺少任何功能性的ndh基因，并且基因组排列明显不同。植物习性与叶绿体基因组组成和排列之间似乎没有任何相关性。
