Related Experiment Video
Updated: Aug 9, 2026

Chromatin Immunoprecipitation Assay for the Identification of Arabidopsis Protein-DNA Interactions In Vivo
Published on: January 14, 2016
Regulation of flowering time by Arabidopsis MSI1
Romaric Bouveret1, Nicole Schönrock, Wilhelm Gruissem
1Institute of Plant Sciences and Zurich-Basel Plant Science Center, ETH Zurich, LFW E17, CH-8092 Zurich, Switzerland.
Abstract:
The transition to flowering is tightly controlled by endogenous programs and environmental signals. We found that MSI1 is a novel flowering-time gene in Arabidopsis. Both partially complemented msi1 mutants and MSI1 antisense plants were late flowering, whereas ectopic expression of MSI1 accelerated flowering. Physiological experiments revealed that MSI1 is similar to genes from the autonomous promotion of flowering pathway. Expression of most known flowering-time genes did not depend on MSI1, but the induction of SOC1 was delayed in partially complemented msi1 mutants. Delayed activation of SOC1 is often caused by increased expression of the floral repressor FLC. However, MSI1 function is independent of FLC. MSI1 is needed to establish epigenetic H3K4 di-methylation and H3K9 acetylation marks in SOC1 chromatin. The presence of these modifications correlates with the high levels of SOC1 expression that induce flowering in Arabidopsis. Together, the control of flowering time depends on epigenetic mechanisms for the correct expression of not only the floral repressor FLC, but also the floral activator SOC1.
Related Concept Videos
Cell Signaling in Plants
Biological Clocks and Seasonal Responses
Morphogenesis
Regulation of Transpiration by Stomata

