Departamento de Bioquímica, Facultad de Química, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Mexico.
Plant Sci. 2012 May;187:39-48. doi: 10.1016/j.plantsci.2012.01.009. Epub 2012 Feb 6.
Phosphorus is an essential element for all living cells, but its availability is often limiting in the soil. Plants have adapted to such limitation and respond to phosphorus deficiency. The soluble inorganic pyrophosphatases (PPase; EC 3.6.1.1) recycle the pyrophosphate produced by many biosynthetic reactions, and may play a role in the plant adaptation to phosphorus deficiency. In this work, three PPase mRNAs were identified from the Phaseolus vulgaris EST international database and their sequences were corroborated and completed using 3'RACE. After design and validation of the appropriate oligonucleotide primers, the PPase mRNA expression was measured by qRT-PCR in leaves, stems, and roots of bean plants grown with 1mM phosphate or under phosphate starvation. The plant tissues were classified according to their position on the plant, and some physiological signs of stress were recorded. qRT-PCR revealed changes in mRNA expression, but not for all isozymes under analysis, and not for all tissues. In addition, changes in the activity of some PPases were observed in zymograms. Our data are consistent with an important role for pyrophosphate in the adaptation of the plant to phosphate starvation.
磷是所有活细胞的必需元素，但在土壤中其有效性往往受到限制。植物已经适应了这种限制，并对磷缺乏做出反应。可溶性无机焦磷酸酶（PPase；EC 3.6.1.1）循环利用许多生物合成反应产生的焦磷酸盐，并且可能在植物适应磷缺乏中发挥作用。在这项工作中，从 Phaseolus vulgaris EST 国际数据库中鉴定出三种 PPase mRNAs，并使用 3'RACE 对其序列进行了验证和补充。在设计和验证适当的寡核苷酸引物后，通过 qRT-PCR 测量在 1mM 磷酸盐或磷酸盐饥饿下生长的豆科植物叶片、茎和根中的 PPase mRNA 表达。根据植物的位置对植物组织进行分类，并记录一些应激的生理迹象。qRT-PCR 显示了 mRNA 表达的变化，但并非所有分析的同工酶都发生了变化，也并非所有组织都发生了变化。此外，在同工酶图谱中观察到一些 PPase 的活性发生了变化。我们的数据表明焦磷酸盐在植物适应磷酸盐饥饿方面发挥了重要作用。
