| Summary: | <p>Abstract</p> <p>Background</p> <p>The ability to induce flowering on demand is of significant biotechnological interest. FT protein has been recently identified as an important component of the mobile flowering hormone, florigen, whose function is conserved across the plant kingdom. We therefore focused on manipulation of both endogenous and heterologous <it>FT </it>genes to develop a floral induction system where flowering would be inhibited until it was induced on demand. The concept was tested in the model plant <it>Arabidopsis thaliana </it>(Arabidopsis).</p> <p>Results</p> <p>Our starting point was plants with strongly delayed flowering due to silencing of <it>FT </it>with an artificial microRNA directed at <it>FT </it>(<it>amiR-FT</it>) <abbrgrp><abbr bid="B1">1</abbr></abbrgrp>. First, we showed that constitutive expression of a heterologous <it>FT </it>gene (<it>FTa1</it>), from the model legume <it>Medicago truncatula</it>, (Medicago) was able to rescue the <it>amiR-FT </it>late-flowering phenotype. In order to induce flowering in a controlled way, the <it>FTa1 </it>gene was then expressed under the control of an alcohol-inducible promoter in the late flowering <it>amiR-FT </it>plants. Upon exposure to ethanol, <it>FTa1 </it>was rapidly up regulated and this resulted in the synchronous induction of flowering.</p> <p>Conclusions</p> <p>We have thus demonstrated a controlled-inducible flowering system using a novel combination of endogenous and heterologous <it>FT </it>genes. The universal florigenic nature of FT suggests that this type of system should be applicable to crops of economic value where flowering control is desirable.</p>
|
|---|