Exogenous proline has favorable effects on growth and browning suppression in rice but not in tobacco
Exogenous proline has favorable effects on growth and browning suppression in rice but not in tobacco
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DOI：
10.1016/j.plaphy.2019.06.032
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发表时间：
2019-09-01
影响因子：
6.5
通讯作者：
Esaka, Muneharu
中科院分区：
文献类型：
--
作者：
Suekawa, Marina;Fujikawa, Yukichi;Esaka, Muneharu
脯氨酸是组成蛋白质的氨基酸之一，在非胁迫和胁迫条件下具有多种作用。本研究通过外源脯氨酸和内源脯氨酸含量的增加，研究了脯氨酸对烟草和水稻生长和布朗宁褐变的影响。外源脯氨酸对烟草和水稻幼苗的生长和布朗宁褐变的影响不同，脯氨酸对烟草幼苗的生长有负面影响，而对水稻幼苗的生长有正面影响。此外，脯氨酸仅对水稻培养细胞的布朗宁有抑制作用，这与脯氨酸含量的增加相一致，而对烟草BY-2细胞无抑制作用。这些结果可能是由于这些细胞对外源脯氨酸摄取活性的差异所致。从Lineweaver-Burk图中可以看出，脯氨酸通过影响酶-底物复合物抑制多酚氧化酶活性，而多酚氧化酶是植物酶促布朗宁的主要因素。脯氨酸可通过抑制PPO活性抑制愈伤组织的布朗宁。
Proline is one of the amino acids that compose proteins and has various roles under non-stress and stress conditions. In this study, we investigated the effect of proline on the growth and browning of two plants, tobacco and rice, by exogenous application and endogenous increase of proline. Exogenous proline had a different effect on the growth and browning between tobacco and rice: proline affected negatively the growth of tobacco seedlings and favorably that of rice seedlings. In addition, proline prevented browning only in rice cultured cells, consistent with the increase of proline contents, but not in tobacco BY-2 cells. These results might be due to the difference of exogenous proline uptake activity in these cells. From the Lineweaver-Burk plots, proline inhibited polyphenol oxidase activity in vitro, which is a major factor of enzymatic browning in plants, by affecting the enzyme-substrate complex. Proline could suppress the browning of the plant callus by inhibition of PPO activity.