PMID- 12232088
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20191120
IS  - 1532-2548 (Electronic)
IS  - 0032-0889 (Print)
IS  - 0032-0889 (Linking)
VI  - 104
IP  - 2
DP  - 1994 Feb
TI  - The Induction of Seed Germination in Arabidopsis thaliana Is Regulated 
      Principally by Phytochrome B and Secondarily by Phytochrome A.
PG  - 363-371
AB  - We examined whether spectrally active phytochrome A (PhyA) and phytochrome B 
      (PhyB) play specific roles in the induction of seed germination in Arabidopsis 
      thaliana (L.) Heynh., using PhyA- and PhyB-null mutants, fre1-1 (A. Nagatani, 
      J.W. Reed, J. Chory [1993] Plant Physiol 102: 269-277) and hy3-Bo64 (J. Reed, 
      P.Nagpal, D.S. Poole, M. Furuya, J. Chory [1993] Plant Cell 5: 147-157). When 
      dormant seeds of each genotype imbibed in the dark on aqueous agar plates, the 
      hy3 (phyB) mutant did not germinate, whereas the fre1 (phyA) mutant germinated at 
      a rate of 50 to 60%, and the wild type (WT) germinated at a rate of 60 to 70%. By 
      contrast, seeds of all genotypes germinated to nearly 100% when plated in 
      continuous irradiation with white or red light. When plated in continuous far-red 
      light, however, frequencies of seed germination of the WT and the fre1 and hy3 
      mutants averaged 14, nearly 0, and 47%, respectively, suggesting that PhyB in the 
      red-absorbing form prevents PhyA-dependent germination under continuous far-red 
      light. When irradiated briefly with red or far-red light after imbibition for 1 
      h, a typical photoreversible effect on seed germination was observed in the fre1 
      mutant and the WT but not in the hy3 mutant. In contrast, when allowed to imbibe 
      in the dark for 24 to 48 h and exposed to red light, the seed germination 
      frequencies of the hy3 mutant were more than 40%. Immunoblot analyses of the 
      mutant seeds showed that PhyB apoprotein accumulated in dormant seeds of the WT 
      and the fre1 mutant as much as in the seeds that had imbibed. In contrast, PhyA 
      apoprotein, although detected in etiolated seedlings grown in the dark for 5 d, 
      was not detectable in the dormant seeds of the WT and the hy3 mutant. The above 
      physiological and immunochemical evidence indicates that PhyB in the 
      far-red-absorbing form was stored in the Arabidopsis seeds and resulted in 
      germination in the dark. Hence, PhyA does not play any role in dark germination 
      but induces germination under continuous irradiation with far-red light. Finally, 
      we examined seeds from a signal transduction mutant, det1, and a det1/hy3 double 
      mutant. The det1 seeds exhibited photoreversible responses of germination on 
      aqueous agar plates, and the det1/hy3 double mutant seeds did not. Hence, DET1 is 
      likely to act in a distinct pathway from PhyB in the photoregulation of seed 
      germination.
FAU - Shinomura, T
AU  - Shinomura T
AD  - Advanced Research Laboratory, Hitachi Ltd., Hatoyama, Saitama, Japan 350-03 
      (T.S., M.F.).
FAU - Nagatani, A
AU  - Nagatani A
FAU - Chory, J
AU  - Chory J
FAU - Furuya, M
AU  - Furuya M
LA  - eng
PT  - Journal Article
PL  - United States
TA  - Plant Physiol
JT  - Plant physiology
JID - 0401224
PMC - PMC159207
EDAT- 1994/02/01 00:00
MHDA- 2002/09/17 10:00
PMCR- 1995/02/01
CRDT- 1994/02/01 00:00
PHST- 1994/02/01 00:00 [pubmed]
PHST- 2002/09/17 10:00 [medline]
PHST- 1994/02/01 00:00 [entrez]
PHST- 1995/02/01 00:00 [pmc-release]
AID - 104/2/363 [pii]
AID - 10.1104/pp.104.2.363 [doi]
PST - ppublish
SO  - Plant Physiol. 1994 Feb;104(2):363-371. doi: 10.1104/pp.104.2.363.