Fernández S V, Staneloni R J
Instituto de Investigaciones Bioquímicas Fundación Campomar, Buenos Aires, Argentina.
Cell Mol Biol (Noisy-le-grand). 1996 Jun;42(4):577-87.
A potato (Solanum tuberosum) genomic library was used to isolate five full-length genes and part of a sixth one, encoding the apoproteins of a light-harvesting complex (LHC). The nucleotide sequences of the five isolated genes showed that they encoded very similar proteins (99.75% to 97.50% identities). The deduced amino acid sequences were homologous to the PSII type I CAB proteins encoded by the Lhcb1 genes. The 5'-flanking regions of the five potato genes shared conserved sequences already detected in other light-responsive genes (62 bp fragment located between the CAAT and TATA boxes containing three GATA motifs). The expression of Lhcb1 genes in potato leaves, stems and roots was analyzed by the primer extension method. At least nine different transcripts can be recognized in leaves. A unique transcript could be detected in stems and not in roots. The regulatory function of the 5'-flanking region of the potato Lhcb12 was analyzed in transgenic tobacco plants. The construct used contained the gusA gene which was under the control of the potato Lhcb12 promoter. Analysis of transgenic plants revealed that the 5'-flanking region (-1300 to +10, relative to the transcription start site) of the Lhcb1*2 gene was sufficient to confer a phytochrome response as well as organ-specific expression.
利用马铃薯（Solanum tuberosum）基因组文库分离出五个全长基因和第六个基因的部分序列，这些基因编码光捕获复合体（LHC）的脱辅基蛋白。五个分离基因的核苷酸序列表明，它们编码的蛋白质非常相似（同一性为99.75%至97.50%）。推导的氨基酸序列与由Lhcb1基因编码的PSII I型CAB蛋白同源。五个马铃薯基因的5'侧翼区域共享在其他光响应基因中已检测到的保守序列（位于CAAT盒和TATA盒之间的62 bp片段，包含三个GATA基序）。通过引物延伸法分析了Lhcb1基因在马铃薯叶、茎和根中的表达。在叶片中可识别出至少九种不同的转录本。在茎中可检测到一种独特的转录本，而在根中未检测到。在转基因烟草植株中分析了马铃薯Lhcb12基因5'侧翼区域的调控功能。所使用的构建体包含受马铃薯Lhcb12启动子控制的gusA基因。对转基因植株的分析表明，Lhcb1*2基因的5'侧翼区域（相对于转录起始位点为-1300至+10）足以赋予光敏色素响应以及器官特异性表达。
