Changes in the expression of carbohydrate metabolism genes during three phases of bud dormancy in leafy spurge
Changes in the expression of carbohydrate metabolism genes during three phases of bud dormancy in leafy spurge
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DOI：
10.1007/s11103-009-9568-9
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发表时间：
2010-05-01
影响因子：
5.1
通讯作者：
Serpe, Marcelo D.
中科院分区：
文献类型：
--
作者：
Chao, Wun S.;Serpe, Marcelo D.
绿叶刺（Euphorbia Esula）的地下不定芽经历了三个明确的休眠，偏见，内部和生态效果的阶段。在这项研究中，通过斩首和对季节性信号的响应，检查了碳水化合物代谢和芽休眠的基因之间的关系。实时PCR用于确定在芽休眠不同阶段的碳水化合物代谢基因的表达水平。在差异调节的基因中，特定的欣快感埃斯拉β-淀粉酶基因（EE-BAM1）的表达增加了100倍，从7月（派纳术）到12月（生态范围）（生态范围）。序列数据分析表明，两个基因EE-BAM1和EE-BAM2可以编码此β-淀粉酶。但是，使用基因特异性底漆对的实时PCR仅放大EE-BAM1，表明EE-BAM2是特定于其他器官或不丰富的。这两个基因的推导氨基酸序列在N末端非常相似，但在C末端不同。两者都包含一个几乎相同的预测的48个氨基酸塑料转运肽。免疫印迹分析鉴定出29 kD（裂解过境肽后成熟的EE-BAM1）和35 kD（未加工的EEBAM1）蛋白。在生长诱导的和季节性样品中，组成型表达了35和29 kD蛋白。免疫定位表明EE-BAM1在芽的芽尖端的细胞胞质中。 EE-BAM1还围绕成熟细胞中的淀粉样细胞朝向芽的底部。这些观察结果表明EE-BAM1可能具有双重功能。用作细胞质中的储备蛋白和淀粉样品表面的降解酶。
Underground adventitious buds of leafy spurge (Euphorbia esula) undergo three well-defined phases of dormancy, para-, endo-, and ecodormancy. In this study, relationships among genes involved in carbohydrate metabolism and bud dormancy were examined after paradormancy release (growth induction) by decapitation and in response to seasonal signals. Real-time PCR was used to determine the expression levels of carbohydrate metabolism genes at different phases of bud dormancy. Among differentially-regulated genes, expression of a specific Euphorbia esula beta-amylase gene (Ee-BAM1) increased 100-fold after growth induction and 16,000-fold from July (paradormancy) to December (ecodormancy). Sequence data analysis indicated that two genes, Ee-BAM1 and Ee-BAM2, could encode this beta-amylase. However, real-time PCR using gene-specific primer pairs only amplified Ee-BAM1, indicating that Ee-BAM2 is either specific to other organs or not abundant. The deduced amino acid sequences of these two genes are very similar at the N-terminal but differ at the C-terminal. Both contain a nearly identical, predicted 48-amino acid plastid transit peptide. Immunoblot analyses identified a 29 kD (mature Ee-BAM1 after cleavage of the transit peptide) and a 35 kD (unprocessed EeBAM1) protein. Both 35 and 29 kD proteins were constitutively expressed in growth-induced and seasonal samples. Immunolocalization indicated that Ee-BAM1 is in the cytosol of cells at the shoot tip of the bud. Ee-BAM1 also surrounds the amyloplasts in mature cells toward the base of the bud. These observations suggests that Ee-BAM1 may have dual functions; serving as reserve protein in the cytosol and as a degrading enzyme at the surface of amyloplasts.