van der Krol A R, Mur L A, de Lange P, Mol J N, Stuitje A R
Department of Genetics, Free University, Amsterdam, Netherlands.
Plant Mol Biol. 1990 Apr;14(4):457-66. doi: 10.1007/BF00027492.
Introduction of a constitutive antisense full-length chalcone synthase (CHS) cDNA gene in petunia can result in an inhibition of flower pigmentation. We have evaluated some of the factors which may be important for the effectiveness of an antisense CHS gene. Antisense CHS genes encoding half-length or quarter-length RNA complementary to the 3' half of CHS mRNA are able to affect flower pigmentation, while a gene encoding RNA complementary to the 5' half of CHS mRNA did not show phenotypic effects in transgenic petunia plants. We demonstrate that the RNA encoded by the latter gene has a much lower average steady-state level in leaf tissue than the RNAs encoded by the other antisense gene constructs. We have compared the CaMV 35S and endogenous CHS promoter strengths and intrinsic stabilities of sense and antisense CHS RNAs. From the data we conclude that the constitutive antisense CHS genes are not likely to provide an excess of antisense RNA compared to the CHS mRNA derived from the endogenous genes. Effective inhibition of flower pigmentation is also observed when the antisense CHS gene is under control of the homologous CHS promoter. The results indicate that the mechanism of antisense inhibition cannot solely operate via RNA duplex formation between sense and antisense RNA.
在矮牵牛中导入组成型反义全长查尔酮合酶（CHS）cDNA基因可导致花色素沉着受到抑制。我们评估了一些可能对反义CHS基因有效性很重要的因素。编码与CHS mRNA 3' 端一半互补的半长或四分之一长RNA的反义CHS基因能够影响花色素沉着，而编码与CHS mRNA 5' 端一半互补的RNA的基因在转基因矮牵牛植株中未表现出表型效应。我们证明，后一种基因编码的RNA在叶片组织中的平均稳态水平比其他反义基因构建体编码的RNA低得多。我们比较了CaMV 35S和内源性CHS启动子强度以及正义和反义CHS RNA的内在稳定性。从数据中我们得出结论，与源自内源性基因的CHS mRNA相比，组成型反义CHS基因不太可能提供过量的反义RNA。当反义CHS基因受同源CHS启动子控制时，也观察到花色素沉着的有效抑制。结果表明，反义抑制机制不能仅通过正义和反义RNA之间形成RNA双链体来起作用。
