Pichersky E, Bernatzky R, Tanksley S D, Cashmore A R
Proc Natl Acad Sci U S A. 1986 Jun;83(11):3880-4. doi: 10.1073/pnas.83.11.3880.
The nuclear gene sequences encoding RBCS, the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (EC 4.1.1.39) from several plants show extensive interspecific divergence but little intraspecific divergence, suggesting that these genes are evolving in concert within a genome. In this study, the nucleotide sequences of two tomato (Lycopersicon esculentum) RBCS genes and a cDNA clone containing the entire coding region of a third tomato RBCS gene were determined. The three genes, designated Rbcs-1, Rbcs-2A, and Rbcs-3A, each belong to a different one of the three RBCS loci in the tomato genome. The nucleotide sequence of Rbcs-1 differs from that of Rbcs-2A and Rbcs-3A by 13.9% and 13.1%, respectively. Rbcs-2A and Rbcs-3A differ from each other by 10.7%. A recently published RBCS gene sequence from tobacco (Nicotiana tabacum) [Mazur, B. J. & Chui, C.-F. (1985) Nucleic Acids Res. 13, 2373-2386] differs by 10.6% and 11.3% from Rbcs-2A and Rbcs-3A, respectively, and by 15.0% from Rbcs-1. Thus the tobacco gene seems to be phylogenetically as closely related to the tomato genes Rbcs-2A and Rbcs-3A as the latter two are to each other, and more closely related to them than Rbcs-1 is. However, the mature part of the polypeptide encoded by the tobacco RBCS gene differs by five and six amino acids from the corresponding region in the polypeptides encoded by Rbcs-2A and Rbcs-3A, respectively, while these two tomato RBCS polypeptides differ from each other in the mature part by a single amino acid. Rbcs-1, whose nucleotide sequence shows higher divergence from both the tobacco RBCS gene and Rbcs-2A and Rbcs-3A, encodes a polypeptide whose mature part differs by eight amino acids from the corresponding region in the tobacco polypeptide but only by three and four amino acids from the corresponding regions of Rbcs-2A- and Rbcs-3A-encoded polypeptides, respectively. Thus, it appears that in the tomato selection has maintained near uniformity of the coding information in the portion of the RBCS genes encoding the mature polypeptides.
编码核酮糖-1,5-二磷酸羧化酶/加氧酶（EC 4.1.1.39）小亚基（RBCS）的核基因序列在几种植物中显示出广泛的种间差异，但种内差异很小，这表明这些基因在一个基因组内协同进化。在本研究中，测定了两个番茄（Lycopersicon esculentum）RBCS基因的核苷酸序列以及包含第三个番茄RBCS基因完整编码区的一个cDNA克隆。这三个基因分别命名为Rbcs-1、Rbcs-2A和Rbcs-3A，它们各自属于番茄基因组中三个RBCS基因座中的不同一个。Rbcs-1的核苷酸序列与Rbcs-2A和Rbcs-3A的核苷酸序列分别相差13.9%和13.1%。Rbcs-2A和Rbcs-3A彼此相差10.7%。最近发表的烟草（Nicotiana tabacum）的一个RBCS基因序列[Mazur, B. J. & Chui, C.-F. (1985) Nucleic Acids Res. 13, 2373 - 2386]与Rbcs-2A和Rbcs-3A分别相差10.6%和11.3%，与Rbcs-1相差15.0%。因此，烟草基因在系统发育上似乎与番茄基因Rbcs-2A和Rbcs-3A的关系如同后两者彼此之间的关系一样密切，并且与它们的关系比与Rbcs-1的关系更密切。然而，烟草RBCS基因编码的多肽的成熟部分与Rbcs-2A和Rbcs-3A编码的多肽的相应区域分别相差5个和6个氨基酸，而这两个番茄RBCS多肽在成熟部分彼此相差1个氨基酸。Rbcs-1的核苷酸序列与烟草RBCS基因以及Rbcs-2A和Rbcs-3A的差异更大，它编码的多肽的成熟部分与烟草多肽的相应区域相差8个氨基酸，但与Rbcs-2A和Rbcs-3A编码的多肽的相应区域分别仅相差3个和4个氨基酸。因此，似乎在番茄中，选择保持了RBCS基因中编码成熟多肽部分的编码信息近乎一致。
