The Biological Laboratories, Harvard University, Cambridge, Massachusetts 02138.
Proc Natl Acad Sci U S A. 1980 Apr;77(4):1832-6. doi: 10.1073/pnas.77.4.1832.
mRNA for the large subunit (LS) of ribulose-1,5-bisphosphate carboxylase [3-phospho-D-glycerate carboxylase (dimerizing), EC 4.1.1.39] of Zea mays is complementary to an uninterrupted 1600-base-pair-long chloroplast DNA sequence that has been mapped precisely within the 4350-base-pair-long chloroplast DNA fragment Bam 9 to which it had been traced earlier [Bedbrook, J. R., Coen, D. M., Beaton, A. R., Bogorad, L. & Rich, A. (1979) J. Biol. Chem. 254, 905-910]. An additional 1400-base-pair-long uninterrupted region that is colinear with a chloroplast RNA has been detected on Bam 9. The transcript from this region is part of a 2200-nucleotide-long RNA. The remainder of the DNA sequence for the 2200-base-pair RNA maps outside Bam 9. The 1600-base-pair LS gene and the gene for the 2200-nucleotide transcript are close to one another. They are separated by an untranscribed intercistronic "gap" about 330 base pairs long. These two closely packed genes are inverted on the chromosome-i.e., their 3' termini are at opposite ends of the untranscribed gap and they map on opposite strands.
玉米的核酮糖-1,5-二磷酸羧化酶大亚基(LS)的 mRNA 与一段长达 1600 个碱基的叶绿体 DNA 序列互补,该序列已被精确地标定在 Bam 9 叶绿体 DNA 片段内,该片段早先已被追踪到[Bedbrook, J. R., Coen, D. M., Beaton, A. R., Bogorad, L. & Rich, A. (1979) J. Biol. Chem. 254, 905-910]。在 Bam 9 上还检测到一个与叶绿体 RNA 共线性的长达 1400 个碱基的未间断区域。该区域的转录本是一个 2200 个核苷酸长的 RNA 的一部分。该 2200 个碱基 RNA 的其余 DNA 序列位于 Bam 9 之外。1600 个碱基的 LS 基因和 2200 个核苷酸转录本的基因彼此靠近。它们被一个大约 330 个碱基对长的未转录的内含子“间隔区”隔开。这两个紧密包装的基因在染色体上是反向的,即它们的 3'末端位于未转录间隔区的两端,并且它们位于相反的链上。