Transforming petals into sepaloid organs in Arabidopsis and oilseed rape: implementation of the hairpin RNA-mediated gene silencing technology in an organ-specific manner.
Oilseed rape ( Brassica napus L.) genotypes with no or small petals are thought to have advantages in photosynthetic activity. The flowers of field-grown oilseed rape form a bright-yellow canopy that reflects and absorbs nearly 60% of the photosynthetically active radiation (PAR), causing a severe yield penalty. Reducing the size of the petals and/or removing the reflecting colour will improve the transmission of PAR to the leaves and is expected to increase the crop productivity. In this study the 'hairpin' RNA-mediated (hpRNA) gene silencing technology was implemented in Arabidopsis thaliana (L.) Heynh. and B. napus to silence B-type MADS-box floral organ identity genes in a second-whorl-specific manner. In Arabidopsis, silencing of B-type MADS-box genes was obtained by expressing B. napus APETALA3( BAP3) or PISTILLATA ( BPI) homologous self-complementary hpRNA constructs under control of the Arabidopsis A-type MADS-box gene APETALA1 ( AP1) promoter. In B. napus, silencing of the BPI gene family was achieved by expressing a similar hpRNA construct as used in Arabidopsis under the control of a chimeric promoter consisting of a modified petal-specific Arabidopsis AP3 promoter fragment fused to the AP1 promoter. In this way, transgenic plants were generated producing male fertile flowers in which the petals were converted into sepals ( Arabidopsis) or into sepaloid petals ( B. napus). These novel flower phenotypes were stable and heritable in both species.
Byzova
Marina
M
Bayer BioScience NV, Jozef Plateaustraat 22, Gent 9000, Belgium.
Verduyn
Christoph
C
De Brouwer
Dirk
D
De Block
Marc
M
D017360:Arabidopsis / Q000235:genetics*; D001483:Base Sequence; D029688:Brassica napus / Q000235:genetics*; D017931:DNA Primers; D035264:Flowers / Q000033:anatomy & histology / Q000235:genetics*; D020868:Gene Silencing; D005821:Genetic Techniques; D009690:Nucleic Acid Conformation; D010641:Phenotype; D030821:Plants, Genetically Modified / Q000235:genetics*; D010957:Plasmids; D018749:RNA, Plant / Q000737:chemistry* / Q000235:genetics*
D017931:DNA Primers; D018749:RNA, Plant