Partial amino acid sequences of a 49 kDa apyrase (ATP diphosphohydrolase, EC 3.6.1.5) from the cytoskeletal fraction of etiolated pea stems were used to derive oligonucleotide DNA primers to generate a cDNA fragment of pea apyrase mRNA by RT-PCR and these primers were used to screen a pea stem cDNA library. Two almost identical cDNAs differing in just 6 nucleotides within the coding regions were found, and these cDNA sequences were used to clone genomic fragments by PCR. Two nearly identical gene fragments containing 8 exons and 7 introns were obtained. One of them (H-type) encoded the mRNA sequence described by Hsieh et al. (1996) (DDBJ/EMBL/GenBank Z32743), while the other (S-type) differed by the same 6 nucleotides as the mRNAs, suggesting that these genes may be alleles. The six nucleotide differences between these two alleles were found solely in the first exon, and these mutation sites had two types of consensus sequences. These mRNAs were found with varying lengths of 3' untranslated regions (3'-UTR). There are some similarities between the 3'-UTR of these mRNAs and those of actin and actin binding proteins in plants. The putative roles of the 3'-UTR and alternative polyadenylation sites are discussed in relation to their possible role in targeting the mRNAs to different subcellular compartments.

中文翻译：

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豌豆 (Pisum sativum) 腺苷三磷酸双磷酸酶基因的编码区结构和 mRNA 变体。


使用来自黄化豌豆茎细胞骨架部分的 49 kDa 腺苷三磷酸双磷酸酶（ATP 二磷酸水解酶，EC 3.6.1.5）的部分氨基酸序列来衍生寡核苷酸 DNA 引物，以通过 RT-PCR 产生豌豆腺苷三磷酸双磷酸酶 mRNA 的 cDNA 片段，并且这些引物是用于筛选豌豆茎 cDNA 文库。发现了两个几乎相同的 cDNA，仅在编码区内有 6 个核苷酸不同，这些 cDNA 序列用于通过 PCR 克隆基因组片段。获得了两个几乎相同的含有8个外显子和7个内含子的基因片段。其中之一（H 型）编码 Hsieh 等人描述的 mRNA 序列。 (1996) (DDBJ/EMBL/GenBank Z32743)，而另一个（S型）与mRNA有相同的6个核苷酸差异，表明这些基因可能是等位基因。这两个等位基因之间的六个核苷酸差异仅在第一个外显子中发现，并且这些突变位点具有两种类型的共有序列。这些 mRNA 具有不同长度的 3' 非翻译区 (3'-UTR)。这些 mRNA 的 3'-UTR 与植物中肌动蛋白和肌动蛋白结合蛋白的 3'-UTR 之间存在一些相似之处。讨论了 3'-UTR 和替代多聚腺苷酸化位点的假定作用及其在将 mRNA 靶向不同亚细胞区室中的可能作用。