转蚕丝芯蛋白基因获得高强纤维棉花植株

采用花粉管通道技术,将棉纤维细胞特异表达启动子(E6)驱动的蚕丝芯蛋白基因导入陆地棉品种"泗棉3号"。共注射600朵花,收获497粒种子。通过GUS报告基因组化检测筛选,获得5株GUS阳性棉株。又经卡那霉素涂叶法鉴定,其中4株具有良好的卡那霉素抗性。用依据E6启动子序列和蚕丝芯蛋白基因序列设计的两对引物,对这5株棉花进行PCR扩增,获得1株转蚕丝芯蛋白基因棉株。纤维品质测定结果表明,这株转蚕丝芯蛋白基因棉花T1代纤维比强度达到34.6cN/tex,比对照"泗棉3号"(比强度为28.6cN/tex)提高了21.0%,T2代纤维比强度比对照平均增高23.3%。

Transformation of Cotton (Gossypium hirsutum L.) with a Silkworm Fibroin Gene to Achieve Strength-enhanced Fiber

A transgenic cotton (Gossypium hirsutum L.) plant of the cultivar "Simian 3" was obtained by using pollen tube-mediated transformation with a chimeric gene which was composed of the fibroin gene, a GUS (β-glucuronidase) gene, and a (neomycin phosphotransferase) gene under the control of a fiber-special E6 promoter. After injection with the transgene into 600 ovaries of the cotton cultivar, 497 seeds were harvested. The seeds were then germinated on 0.7%(w/v) agar-solidified MS medium, followed by undergoing a histochemical GUS assay and a kanamycin leaf-spotting test. Five seedlings survived after the GUS screening, and 4 of the GUS-positive plants passed the selection for Kan resistance. In order to detect the presence of the fibroin gene in the putative transgenic plants which survived after the above selections, fibroin-specific PCR analysis were performed, and 1 plant showed amplified product bands of the expected size. The 2.5% span length(SL), strength, and micronaire of the fiber were determined to evaluate the fiber quality of the silkworm fibroin-transgenic cotton, the results indicated the fiber-strength of the T_1 progeny was increased by 21.0% to 34.6 cN/tex, and that of T_2 progeny was increased by 23.3%.