Regulatory Department, Centro de Tecnologia Canavieira (CTC), Piracicaba, Brazil.
Hjelle Advisors LLC, Clayton, MO, USA.
GM Crops Food. 2019;10(4):208-219. doi: 10.1080/21645698.2019.1651191. Epub 2019 Aug 20.
A Cry1Ac-expressing sugarcane cultivar, CTC91087-6, has been developed by Centro de Tecnologia Canavieira (CTC) to be resistant to the sugarcane borer (). This genetically modified event was developed using -mediated transformation and the help of the selectable marker phosphinothricin N-acetyltransferase (PAT) expressed from gene. We describe here a detailed characterization of CTC91087-6 event with respect to protein expression, nutritional composition, and assessment of its derived DNA and proteins in raw sugar. Expression of the Cry1Ac and PAT (bar) proteins produced by CTC91087-6 was evaluated in different tissues and at different times during the growing season. The new proteins are preferentially expressed in leaves, are produced at low levels in stalks, and are near the limits of detection in root tissues. The levels of Cry1Ac were much higher than PAT in all evaluated tissues. Furthermore, Cry1Ac levels in CTC91087-6 leaves are stable at various times during sugarcane cultivation cycle, assuring borer control throughout the complete crop cycle. Assessment of CTC91087-6 tissues for key food and feed nutrients as recommended by OECD to assess the safety of new varieties of sugarcane showed compositional equivalence to the conventional counterpart CTC9001 and to other commercial sugarcane varieties used as references. Raw sugar samples produced from CTC91087-6 did not contain DNA corresponding to and genes nor DNA specifically derived from CTC91087-6. In a similar way, there is no detection of Cry1Ac and PAT proteins in raw sugar produced from CTC91087-6. Taken together these results show that CTC91087-6 stably expresses Cry1Ac and PAT proteins and is substantially equivalent to the conventional counterpart CTC9001.
培育了一个表达 Cry1Ac 的甘蔗品种 CTC91087-6,使其能够抵抗甘蔗螟虫()。该转基因事件是利用介导的转化和选择标记物草丁膦乙酰转移酶(PAT)的表达开发的,该标记物来自基因。我们在这里详细描述了 CTC91087-6 事件的特性,包括蛋白表达、营养成分以及对原糖中衍生 DNA 和蛋白的评估。在不同的组织和不同的生长季节,评估了 CTC91087-6 产生的 Cry1Ac 和 PAT(bar)蛋白的表达。新蛋白在叶片中优先表达,在茎中低水平表达,在根组织中接近检测极限。Cry1Ac 的水平在所有评估的组织中都远高于 PAT。此外,在甘蔗种植周期的不同时间,CTC91087-6 叶片中的 Cry1Ac 水平稳定,确保了整个作物周期内对螟虫的控制。根据 OECD 的建议,评估 CTC91087-6 组织中的关键食物和饲料营养成分,以评估新甘蔗品种的安全性,结果表明其与对照品种 CTC9001 和其他用作参考的商业甘蔗品种在成分上具有等效性。从 CTC91087-6 生产的原糖样品中没有检测到和基因的 DNA,也没有专门从 CTC91087-6 衍生的 DNA。同样,从 CTC91087-6 生产的原糖中也没有检测到 Cry1Ac 和 PAT 蛋白。综上所述,这些结果表明 CTC91087-6 稳定表达 Cry1Ac 和 PAT 蛋白,并且与对照品种 CTC9001 基本等效。