A Brassica napus gene family which shows sequence similarity to ascorbate oxidase is expressed in developing pollen. Molecular characterization and analysis of promoter activity in transgenic tobacco plants.
A Brassica napus gene family which shows sequence similarity to ascorbate oxidase is expressed in developing pollen. Molecular characterization and analysis of promoter activity in transgenic tobacco plants.
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DOI：
10.1046/j.1365-313x.1992.t01-32-00999.x
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发表时间：
1992-05
期刊：
影响因子：
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通讯作者：
Diego Albani;R. Sardana;L. Robert;I. Altosaar;P. Arnison;S. Fabijanski
中科院分区：
文献类型：
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作者：
Diego Albani;R. Sardana;L. Robert;I. Altosaar;P. Arnison;S. Fabijanski
命名为Bp 10的基因组克隆包含B的花粉特异性小基因家族的成员。油菜。Bp 10基因家族的表达在早期双核小孢子中最高，在成熟的三核花粉中显著下降。Bp 10基因的同源物在其他植物物种的花粉中表达。在用嵌合Bp 10启动子/GUS构建体转化的烟草植物中证实了基因组克隆中所含基因的花粉特异性表达。396 bp的启动子片段足以指导转基因植物中强且正确的空间和时间表达。Bp 10基因家族编码62 kDa的蛋白质，与黄瓜和南瓜抗坏血酸氧化酶（AAOs）显示约30%的序列同一性。然而，AAO活性中心在Bp 10产物中不保守，这表明这些蛋白质的进化关系但不同的酶活性。重组Bp 10蛋白在E.大肠杆菌抑制细菌在基本培养基上的生长，表明细菌中产生酶活性多肽。AAO活性与重组蛋白的表达无相关性。此外，影响AAO活性的物质似乎不影响细菌中产生的蛋白质的抑制活性。然而，如碳酸氢钠或气态CO2存在下细菌生长的拯救所示，Bp 10蛋白活性可通过CO2水平进行调节。
The genomic clone named Bp10 contains a member of a small pollen-specific gene family of B. napus. The expression of the Bp10 gene family is maximal in early binucleate microspores and declines considerably in mature trinucleate pollen. Homologues of the Bp10 genes are expressed in the pollen of other plant species. The pollen-specific expression of the gene contained in the genomic clone was confirmed in tobacco plants transformed with a chimeric Bp10 promoter/GUS construct. A promoter fragment of 396 bp is sufficient to direct a strong and correct spatial and temporal expression in transgenic plants. The Bp10 gene family codes for proteins of 62 kDa showing approximately 30% sequence identify to cucumber and pumpkin ascorbate oxidases (AAOs). However, the AAO active centres are not conserved in the Bp10 products, suggesting an evolutionary relationship but a different enzymatic activity for these proteins. Expression of a recombinant Bp10 protein in E. coli inhibits bacterial growth on minimal medium, suggesting the production of an enzymatically active polypeptide in bacteria. No AAO activity could be correlated with the expression of the recombinant protein. Moreover, substances affecting AAO activity do not appear to influence the inhibitory activity of the protein produced in bacteria. However, as indicated by the rescue of bacterial growth in the presence of sodium bicarbonate or gaseous CO2, the Bp10 protein activity could be modulated by CO2 levels.