Chen Grace Q, He Xiaohua, McKeon Thomas A
Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 800 Buchanan Street, Albany, California 94710, USA.
J Agric Food Chem. 2005 Mar 23;53(6):2358-61. doi: 10.1021/jf040405t.
Castor oil is the only commercial source of ricinoleic acid and has numerous industrial applications. Among the factors limiting domestic production of castor oil is the presence of the toxin ricin and its less toxic homologue Ricinus communis agglutinin (RCA) in seeds. Although the sequences of ricin and RCA genes are known, their transcriptional expression patterns have not been distinguished due to their high degree of sequence similarity. As the information is critical for assessing success in developing a ricin-free castor crop using genetic silencing, we have designed a gene specific reverse transcription-polymerase chain reaction (RT-PCR) assay to examine the expression of the ricin and RCA genes in developing seeds. The results show that the ricin and RCA mRNA are highly abundant in seeds during the development of endosperm, and the expression pattern is similar to that observed in the Northern analysis. The RT-PCR results can be confirmed by a simple RT-PCR-based restriction fragment analysis.
蓖麻油是蓖麻油酸的唯一商业来源，并且有许多工业应用。限制国内蓖麻油生产的因素之一是种子中存在毒素蓖麻毒素及其毒性较低的同源物蓖麻凝集素（RCA）。尽管蓖麻毒素和RCA基因的序列已知，但由于它们高度的序列相似性，它们的转录表达模式尚未区分。由于该信息对于评估使用基因沉默培育无蓖麻毒素蓖麻作物的成功与否至关重要，我们设计了一种基因特异性逆转录-聚合酶链反应（RT-PCR）分析方法，以检测蓖麻毒素和RCA基因在发育种子中的表达。结果表明，在胚乳发育过程中，蓖麻毒素和RCA mRNA在种子中高度丰富，并且表达模式与在Northern分析中观察到的相似。RT-PCR结果可以通过基于简单RT-PCR的限制性片段分析来证实。
