A dominant mutation in the pea PHYA gene confers enhanced responses to light and impairs the light-dependent degradation of phytochrome A.
Phytochrome A (phyA) is an important photoreceptor controlling many processes throughout the plant life cycle. It is unique within the phytochrome family for its ability to mediate photomorphogenic responses to continuous far-red light and for the strong photocontrol of its transcript level and protein stability. Here we describe a dominant mutant of garden pea (Pisum sativum) that displays dramatically enhanced responses to light, early photoperiod-independent flowering, and impaired photodestruction of phyA. The mutant carries a single base substitution in the PHYA gene that is genetically inseparable from the mutant phenotype. This substitution is predicted to direct the replacement of a conserved Ala in an N-terminal region of PHYA that is highly divergent between phyA and other phytochromes. This result identifies a region of the phyA photoreceptor molecule that may play an important role in its fate after photoconversion.
Weller
James L
JL
School of Plant Science, University of Tasmania, Hobart, Tasmania 7001, Australia. jim.weller@utas.edu.au
Batge
Shona L
SL
Smith
Jennifer J
JJ
Kerckhoffs
L Huub J
LH
Sineshchekov
Vitaly A
VA
Murfet
Ian C
IC
Reid
James B
JB
D000595:Amino Acid Sequence; D001483:Base Sequence; D017124:Conserved Sequence; D017931:DNA Primers; D005799:Genes, Dominant; D017343:Genes, Plant; D008027:Light; D008969:Molecular Sequence Data; D018532:Pisum sativum / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D010641:Phenotype; D010834:Phytochrome / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects; D051942:Phytochrome A; D018749:RNA, Plant / Q000235:genetics / Q000302:isolation & purification; D036226:Seedlings / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects; D016415:Sequence Alignment
D017931:DNA Primers; D051942:Phytochrome A; D018749:RNA, Plant; D010834:Phytochrome