Department of Biotechnology, Interdisciplinary Program of Graduate School for Bioenergy and Biomaterials, Bioenergy Research Center, Chonnam National University, Gwangju, 500-757, Korea.
Bioprocess Biosyst Eng. 2012 Jan;35(1-2):205-10. doi: 10.1007/s00449-011-0615-y. Epub 2011 Sep 11.
Tyramine, one of the various biogenic amines found in plants, is derived from the aromatic L-amino acid tyrosine through the catalytic reaction of tyrosine decarboxylase (TYDC). Tyramine overproduction by constitutive expression of TYDC in rice plants leads to stunted growth, but an increased number of tillers. To regulate tyramine production in rice plants, we expressed TYDC under the control of a methanol-inducible plant tryptophan decarboxylase (TDC) promoter and generated transgenic T(2) homozygous rice plants. The transgenic rice plants showed normal growth phenotypes with slightly increased levels of tyramine in seeds relative to wild type. Upon treatment with 1% methanol, the transgenic rice leaves produced large amounts of tyramine, whereas no increase in tyramine production was observed in wild-type plants. The methanol-induced accumulation of tyramine in the transgenic rice leaves was inversely correlated with the tyrosine level. These data indicate that tyramine production in rice plants can be artificially controlled using the methanol-inducible TDC promoter, suggesting that this promoter could be used to selectively induce the expression of other proteins or metabolites in rice plants.
酪胺是植物中发现的各种生物胺之一，通过芳香族 L-氨基酸酪氨酸的酪氨酸脱羧酶（TYDC）催化反应产生。在水稻植物中通过组成型表达 TYDC 导致生长迟缓，但分蘖数增加。为了调节水稻植物中的酪胺产生，我们在甲醇诱导的植物色氨酸脱羧酶（TDC）启动子的控制下表达 TYDC，并生成了转基因 T（2）纯合子水稻植物。转基因水稻植物表现出正常的生长表型，与野生型相比，种子中的酪胺水平略有增加。用 1%甲醇处理时，转基因水稻叶片产生大量的酪胺，而野生型植物中没有观察到酪胺产量增加。转基因水稻叶片中甲醇诱导的酪胺积累与酪氨酸水平呈负相关。这些数据表明，使用甲醇诱导的 TDC 启动子可以人为控制水稻植物中的酪胺产生，这表明该启动子可用于在水稻植物中选择性诱导其他蛋白质或代谢物的表达。
