Organ-specific gene expression in potato: Isolation and characterization of tuber-specific cDNA sequences
Organ-specific gene expression in potato: Isolation and characterization of tuber-specific cDNA sequences
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马铃薯器官特异性基因表达：块茎特异性 cDNA 序列的分离和表征
DOI：
10.1007/bf00333264
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
L. Willmitzer
中科院分区：
文献类型：
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作者：
S. Rosahl;P. Eckes;J. Schell;L. Willmitzer
摘要对从马铃薯（Solanum tuberosum）块茎中的polyA+RNA 建立的cDNA 文库进行了分析，以了解在块茎中特异性转录的序列。使用叶、根、茎和块茎中的 RNA，通过差异杂交测定筛选 8000 多个 cDNA 克隆，产生了四种不同类别的 cDNA 克隆。根据它们杂交的 mRNA 的大小分布，它们可以进一步分为两组。因此，包含cDNA克隆pcT700、pcT800和pcT1500的第一组在每种情况下与单一RNA种类互补。杂交选择/体外翻译数据表明，其中一个克隆，即 pcT1500，源自编码马铃薯管的主要储存蛋白的 RNA，即 40 kd 物种（称为“patatin”）。由 cDNA 克隆 pcTs6 代表的第二组没有显示与不同 RNA 物种的杂交，而是与涂片杂交。 Northern 和半定量 RNA 斑点印迹分析表明，与叶、茎和根组织相比，除 pcTs6 之外的所有克隆在块茎中的表达至少高出 100-500 倍。基因组印迹分析表明，除 pcTs6 外，所有克隆均由小型多基因家族编码。用分离的细胞核进行的径流实验表明，pcT1500 的器官特异性表达在转录水平受到控制，而就 pcT800 和 pcTs6 而言，控制似乎主要在转录后水平发挥作用。对匍匐茎、气生块茎和组织培养中生长的块茎进行的 RNA 点印迹分析表明，与分离的 cDNA 克隆相对应的基因在这些组织中具有活性，尽管其水平低于在地下生长的块茎中观察到的水平。
SummaryA cDNA library established from polyA+RNA from tubers of potato (Solanum tuberosum) was analysed for sequences specifically transcribed in tubers. Screening more than 8000 cDNA clones in a differential hybridization assay using RNA from leaves, roots, stems and tubers resulted in four different classes of cDNA clones. These could be categorized further into two groups according to the size distribution of mRNAs to which they hybridize. Thus the first group comprising cDNA clones pcT700, pcT800 and pcT1500 were in each case complementary to a single RNA species. Hybrid select/in vitro translation data indicate that one of these clones, i.e. pcT1500, is derived from an RNA encoding the major storage protein of potato tubes, i.e. a 40 kd species (called “patatin”).The second group represented by the cDNA clone pcTs6 did not show hybridization to a distinct RNA species, but rather to a smear. Northern and semiquantitative RNA dot blot assays demonstrate that the expression of all clones except pcTs6 is higher by at least a factor 100–500 in tubers compared to leaf, stem and root tissue. Genomic blot analysis shows that except for pcTs6 all clones are encoded by small multigene families.Run-off experiments performed with isolated nuclei indicate that the organ-specific expression of pcT1500 is controlled at the level of transcription, whereas in the case of pcT800 and pcTs6 the control seems to be exerted predominantly at the post-transcriptional level. RNA dot blot analysis of stolons, air-borne tubers and tubers grown in tissue culture indicate that the genes corresponding to the isolated cDNA clones are active in these tissues, albeit at levels which are lower than those observed in tubers grown underground.