Organ-specific modulation of gene expression in transgenic plants using antisene RNA

Abstract

We have shown leaf-specific inhibition GUS gene expression in transgenic Nicotiana plants using an antisense RNA with a 41-base homology spanning the translation start codon of the gene. GUS was expressed from the nominally constitutive 35S promoter and the antisense RNA was expressed from the light-regulated ca/b promoter of Arabidopsis thaliana. A range of GUS inhibition from 0 to 100% was obtained by screening a small population of transgenic plants and the specific levels of inhibition observed were stably inherited in two generations. An antiGUS 'gene' dosage effect was observed in plants which were homozygous for antiGUS. RNA detection results suggest that duplex formation with the 41 base pair antiGUS RNA destabilized the GUS mRNA and that an excess of antisense RNA was not required. Our results demonstrate the potential of antisense RNA as a strategy for obtaining plant mutants, especially 'down mutations' in essential genes where only a short 5' sequence of the mRNA is required. They also suggest that the 'position effect' on gene expression could be used in conjunction with an antisense RNA strategy to provide a versatile approach for crop improvement.

Isolation of the tomato AGAMOUS gene TAG1 and analysis of its homeotic role in transgenic plants.

“…We chose to inhibit gene function by means of antisense RNA (Cannon et al, 1990;Mol et al, 1990) and in parallel to overexpress the gene in ectopic organs. Inhibition of MADS box genes by antisense RNA has not yet been reported, but Angenent et al (1993) obtained two plants in which cosuppression of the petunia gene FBP1 resulted in a phenocopy of mutations in B group genes, van der Krol et al (1993) have also employed cosuppression in petunia to help identify the pMADSI gene as responsible for the green petal mutation.…”

Molecular cloning and functional analysis of the second gene encoding glutamate dehydrogenase in triticale

“…Due to the low level of complementarity between RNA in the formed duplexes, the endogenous RNA is not silenced; therefore, the transcript was still detectable but interfered with the translation of endogenous transcripts responsible for the synthesis of the b subunit. Moreover, according to gene-silencing studies concerning carried out by Cannon et al (1990) and Oeller et al (1991), during inhibition by antisense RNA expression, reduced expression of endogenous gene is often observed. Therefore, a different silencing model was proposed in which antisense RNA forms duplexes with the corresponding endogenous sense RNA.…”

Accumulation of plant antenna complexes is regulated by post-transcriptional mechanisms in tobacco.

“…Our results thus show that it might be possible to modulate individually the expression even of highly homologous endogenous genes by short and therefore gene-specific sequences. A stretch of only 41 nucleotides may be sufficient for antisense inhibition, as shown for the artificial marker gene Gus which encodes P-glucuronidase in transgenic tobacco (Cannon et al, 1990).…”