H. Gabrys et al., INTERACTION BETWEEN PHYTOCHROME AND THE BLUE-LIGHT PHOTORECEPTOR SYSTEM IN MOUGEOTIA - TEMPERATURE-DEPENDENCE, Journal of photochemistry and photobiology.B, Biology, 38(1), 1997, pp. 35-39
The interaction between cryptochrome and phytochrome, the pigments con
trolling the face-to-profile movement of Mougeotia chloroplasts, was i
nvestigated at 2 degrees C. The response was induced with blue, follow
ed by red, light flashes of approximately 6 ms. After a dark period re
quired for interaction, the remaining P-fr gradient was cancelled with
far-red light. The delay between the blue and red flashes was varied
to study the effect of low temperature on the lifetime of the hypothet
ical blue signal carrier generated in the cryptochrome-mediated reacti
on. The Q(10) quotient of 2.7-3.0 was calculated from the delay curves
measured at 17 and 2 degrees C, The interaction between the blue sign
al carrier and P-fr proceeded effectively at 2 degrees C and reached a
maximum after 10 min. Contrary to previously reported results, the te
mperature of 2 degrees C did not block the phytochrome-mediated profil
e-to-face movement induced by red light flashes or continuous irradiat
ion. (C) 1997 Elsevier Science S.A.