Individual Members of the Cab Gene Family Differ Widely in Fluence Response.
Chlorophyll a/b-binding protein genes (Cab genes) can be extremely sensitive to light. Transcript accumulation following a red light pulse increases with fluence over 8 orders of magnitude (L.S. Kaufman, W.F. Thompson, W.R. Briggs [1984] Science 226: 1447-1449). We have constructed fluence-response curves for individual Cab genes. At least two Cab genes (Cab-8 and AB96) show a very low fluence response to a single red light pulse. In contrast, two other Cab genes (AB80 and AB66) fail to produce detectable transcript following a single pulse of either red or blue light but are expressed in continuous red light. Thus, very low fluence responses and high irradiance responses occur in the same gene family.
White
M. J.
MJ
Department of Biology, Saint Mary's University, Halifax, Nova Scotia, B3H 3C3 Canada (M.J.W.).
Kaufman
L. S.
LS
Horwitz
B. A.
BA
Briggs
W. R.
WR
Thompson
W. F.
WF