Smith C J, Watson C F, Bird C R, Ray J, Schuch W, Grierson D
Department of Physiology and Environmental Science, University of Nottingham School of Agriculture, Loughborough, UK.
Mol Gen Genet. 1990 Dec;224(3):477-81. doi: 10.1007/BF00262443.
Tomato plants were transformed with a chimaeric polygalacturonase (PG) gene, designed to produce a truncated PG transcript constitutively. In these plants expression of the endogenous PG gene was inhibited during ripening, resulting in a substantial reduction in PG mRNA and enzyme accumulation. This inhibition was comparable to that achieved previously using antisense genes. The expression of the truncated gene in ripe fruit was substantially lower than its expression in green fruit. Thus expression of both the endogenous and truncated genes is reduced in ripe fruit in which both are active. The implication of this observation is discussed in relation to the possible mechanism whereby sense constructs inhibit gene expression.
用一个嵌合多聚半乳糖醛酸酶（PG）基因转化番茄植株，该基因设计用于组成型产生截短的PG转录本。在这些植株中，内源PG基因在成熟过程中的表达受到抑制，导致PG mRNA和酶积累大幅减少。这种抑制作用与先前使用反义基因所达到的效果相当。截短基因在成熟果实中的表达明显低于其在绿色果实中的表达。因此，在两个基因都活跃的成熟果实中，内源基因和截短基因的表达都降低了。结合有义构建体抑制基因表达的可能机制对这一观察结果的意义进行了讨论。
