Abstract
Phototropins act as photoreceptor in blue light (BL) dependent responses in plants. However, components involved in phototropin signaling are largely unknown. Using a yeast two-hybrid screening, dynein light chain like protein (vfDLC) of Vicia faba was isolated as an interactor of vfphot1a. DLC is a subunit of the dynein complex which translocate along microtubules. Far western and two-hybrid analysis revealed that vfDLC binds to the N-terminal region of vfphot1a but not to vfphot1b. Interaction between GST-vfDLC and vfphot was confirmed by pull-down assay. Northern analysis revealed that the transcription level of vfDLC was higher in guard cells than in other cell types. vfDLC-GFP showed fluorescence spots on the plasma membrane in guard cells. Treatment of plant materials with microtubule-depolymerizing herbicides partially inhibited BL dependent H+-pumping and stomatal opening. These results suggest that vfDLC may be a component of BL dependent signal transduction in stomatal opening.
