Yamagishi Noriko, Yoshikawa Nobuyuki
Plant Pathology Laboratory, Faculty of Agriculture, Iwate University, Iwate, Morioka, Japan.
Plant Mol Biol. 2009 Sep;71(1-2):15-24. doi: 10.1007/s11103-009-9505-y. Epub 2009 Jun 4.
Virus-induced gene silencing (VIGS) has great potential as a reverse-genetics tool in plant genomics. In this study, we examined the potential of VIGS in soybean seeds and the emergence stage of soybean plants using Apple latent spherical virus (ALSV) vectors. Inoculation of an ALSV vector (soyPDS-ALSV) carrying a fragment of the soybean phytoene desaturase (soyPDS) gene into soybean seedlings resulted in a highly uniform photo-bleached phenotype, typical of PDS inhibition, on the upper leaves throughout plant growth. The photo-bleached phenotype was also found on all immature pods, all seed coats, and about 50% embryos of seeds on soybean plants infected with soyPDS-ALSV. Infection with an ALSV vector (soyIFS2-ALSV) having a fragment of soybean isoflavone synthase 2 (soyIFS2) gene also led to a reduction of the levels of both soyIFS2- and soyIFS1- mRNAs and an isoflavone content in the cotyledons of about 36% mature seeds of infected soybean plants. Furthermore, VIGS of soyPDS was induced in the next generation plants by the seed transmission of soyPDS-ALSV. Thus ALSV vectors will be useful for studying gene functions in the reproductive stages and early growth stages, such as emergence and cotyledon stages, in addition to the vegetative stages of soybean plants.
病毒诱导的基因沉默（VIGS）作为植物基因组学中的一种反向遗传学工具具有巨大潜力。在本研究中，我们使用苹果潜隐球形病毒（ALSV）载体检测了VIGS在大豆种子和大豆植株出苗期的潜力。将携带大豆八氢番茄红素去饱和酶（soyPDS）基因片段的ALSV载体（soyPDS-ALSV）接种到大豆幼苗中，在植株整个生长过程中，上部叶片出现了高度一致的光漂白表型，这是PDS抑制的典型表现。在感染了soyPDS-ALSV的大豆植株上，所有未成熟豆荚、所有种皮以及约50%的种子胚上也发现了光漂白表型。用携带大豆异黄酮合酶2（soyIFS2）基因片段的ALSV载体（soyIFS2-ALSV）进行感染，也导致受感染大豆植株约36%成熟种子子叶中soyIFS2和soyIFS1 mRNA水平以及异黄酮含量降低。此外，soyPDS-ALSV通过种子传播在下一代植株中诱导了soyPDS的VIGS。因此，除了大豆植株的营养生长阶段外，ALSV载体将有助于研究大豆植株生殖阶段和早期生长阶段（如出苗期和子叶期）的基因功能。
