The movement of COP1 out of the nucleus prevents it from binding to and suppressing the activity of transcription factors that promote photomorphogenesis. It interacts with COP1 in the nucleus. Plants expressing the antisense of CIP4 would not show the characteristic inhibition of hypocotyl elongation observed in response to blue, red or white light irradiation. Only successful injections into the cytoplasm are capable of activating signal transduction and the controls never activate either pathway, therefore the results support a role for the injected molecules in the pathway that is activated. Describe the set-up and results for an experiment whose results indicate that both phytochrome and calcium are involved in the process of wheat protoplast swelling.
Protoplast swelling only occurs in the prescence of red light and calcium.
The gravity stimulus rapidly and asymmetrically increases the level of IP 3 in maize pulvini. The calcium current directed by gravity appears to have a much greater rate of efflux from the top of the cell than entry into the bottom of the cell. In order for this current to be sustained any significant amount of time, it would seem that calcium would have to be released from internal stores. Describe this evidence. Knocking out the cry1 and cry2 genes does not block this blue light response, but knocking out the nph1 gene does.