Laboratory of Cell Biology, The Rockefeller University, 1230 York Avenue, 10021, New York, NY, USA.
Plant Mol Biol. 1987 May;9(3):205-16. doi: 10.1007/BF00166457.
We report the isolation and characterization of a tomato nuclear gene encoding a chlorophyll a/b-binding (CAB) protein of photosystem I (PSI). The coding nucleotide sequence of the gene, designated Cab-6B, is different at eight positions from that of a previously isolated cDNA clone derived from the Cab-6A gene, but the two genes encode identical proteins. Sequence comparison with the cDNA clone revealed the presence of three short introns in Cab-6B. Genetic mapping experiments demonstrate that Cab-6A and Cab-6B are tightly linked and reside on chromosome 5, but the physical distance between the two genes is at least 7 kilobases. Cab-6A and Cab-6B have been designated Type I PSI CAB genes. They are the only two genes of this branch of the CAB gene family in the tomato genome, and they show substantial divergence to the genes encoding CAB polypeptides of photosystem II. The Type I PSI CAB genes, like the genes encoding PSII CAB proteins, are highly expressed in illuminated leaf tissue and to a lesser extent in other green organs.
我们报告了一种番茄核基因的分离和特性，该基因编码光系统 I（PSI）的叶绿素 a/b 结合（CAB）蛋白。该基因的编码核苷酸序列，被命名为 Cab-6B，与先前从 Cab-6A 基因中分离的 cDNA 克隆在八个位置上有所不同，但这两个基因编码相同的蛋白质。与 cDNA 克隆的序列比较表明，Cab-6B 中有三个短内含子。遗传图谱实验表明，Cab-6A 和 Cab-6B 紧密连锁，位于第 5 号染色体上，但这两个基因之间的物理距离至少为 7 千碱基。Cab-6A 和 Cab-6B 被指定为 I 型 PSI CAB 基因。它们是番茄基因组中这一分支的 CAB 基因家族的唯二两个基因，与编码 PSII CAB 多肽的基因有很大的差异。I 型 PSI CAB 基因与编码 PSII CAB 蛋白的基因一样，在光照叶组织中高度表达，在其他绿色器官中表达程度较低。
