Abstract
Translatable phytochrome mRNA represents ≈5 × 10-3% of the total poly(A)-RNA present in etiolated Avena seedlings, as determined by incorporation of radioactivity into the immunoprecipitable apoprotein in a cell-free translation system. Irradiation of such seedlings with 5-s red light induces a decline in this mRNA that is detectable within 15-30 min, shows a 50% reduction within 50-60 min, and results in a >95% reduction within 2 hr. The effect of the red light pulse is reversed by an immediately subsequent far-red pulse to the level of the far-red-light control, indicating that phytochrome exerts autoregulatory control over its own translatable mRNA level. This result necessitates revision of existing concepts of how phytochrome concentrations are modulated in vivo. Red-light dose-response curves show that the response is sensitive to very low light levels. Conversion of <1% of the total cellular phytochrome to the biologically active far-red-absorbing form is sufficient to induce ≈60% of the maximal response, and 20% far-red-absorbing form saturates the response. The observed change in translatable phytochrome mRNA level is one of the most rapid phytochrome-induced alterations in any cellular mRNA yet recorded. Thus, autoregulation of phytochrome mRNA provides an attractive opportunity to examine the early sequence of events in phytochrome control of gene expression.
Keywords: regulatory photoreceptor, dose-response curves, rapid regulation, low-abundance mRNA, gene expression
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- Apel K. Phytochrome-induced appearance of mRNA activity for the apoprotein of the light-harvesting chlorophyll a/b protein of barley (Hordeum vulgare). Eur J Biochem. 1979 Jun;97(1):183–188. doi: 10.1111/j.1432-1033.1979.tb13101.x. [DOI] [PubMed] [Google Scholar]
- Apel K. The protochlorophyllide holochrome of barley (Hordeum vulgare L.). Phytochrome-induced decrease of translatable mRNA coding for the NADPH: protochlorophyllide oxidoreductase. Eur J Biochem. 1981 Nov;120(1):89–93. doi: 10.1111/j.1432-1033.1981.tb05673.x. [DOI] [PubMed] [Google Scholar]
- Bantle J. A., Maxwell I. H., Hahn W. E. Specificity of oligo (dT)-cellulose chromatography in the isolation of polyadenylated RNA. Anal Biochem. 1976 May 7;72:413–427. doi: 10.1016/0003-2697(76)90549-2. [DOI] [PubMed] [Google Scholar]
- Berger S. L., Birkenmeier C. S. Inhibition of intractable nucleases with ribonucleoside--vanadyl complexes: isolation of messenger ribonucleic acid from resting lymphocytes. Biochemistry. 1979 Nov 13;18(23):5143–5149. doi: 10.1021/bi00590a018. [DOI] [PubMed] [Google Scholar]
- Fry K. T., Mumford F. E. Isolation and partial characterization of a chromophore-peptide fragment from pepsin digests of phytochrome. Biochem Biophys Res Commun. 1971 Dec 17;45(6):1466–1473. doi: 10.1016/0006-291x(71)90185-9. [DOI] [PubMed] [Google Scholar]
- Hunt R. E., Pratt L. H. Phytochrome radioimmunoassay. Plant Physiol. 1979 Aug;64(2):327–331. doi: 10.1104/pp.64.2.327. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ivarie R. D., Jones P. P. A rapid sensitive assay for specific protein synthesis in cells and in cell-free translations: use of Staphylococcus aureus as an adsorbent for immune complexes. Anal Biochem. 1979 Aug;97(1):24–35. doi: 10.1016/0003-2697(79)90322-1. [DOI] [PubMed] [Google Scholar]
- Kessler S. W. Rapid isolation of antigens from cells with a staphylococcal protein A-antibody adsorbent: parameters of the interaction of antibody-antigen complexes with protein A. J Immunol. 1975 Dec;115(6):1617–1624. [PubMed] [Google Scholar]
- Kidd G. H., Pratt L. H. Phytochrome destruction: an apparent requirement for protein synthesis in the induction of the destruction mechanism. Plant Physiol. 1973 Oct;52(4):309–311. doi: 10.1104/pp.52.4.309. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
- Laskey R. A. The use of intensifying screens or organic scintillators for visualizing radioactive molecules resolved by gel electrophoresis. Methods Enzymol. 1980;65(1):363–371. doi: 10.1016/s0076-6879(80)65047-2. [DOI] [PubMed] [Google Scholar]
- Pelham H. R., Jackson R. J. An efficient mRNA-dependent translation system from reticulocyte lysates. Eur J Biochem. 1976 Aug 1;67(1):247–256. doi: 10.1111/j.1432-1033.1976.tb10656.x. [DOI] [PubMed] [Google Scholar]
- Pratt L. H., Kidd G. H., Coleman R. A. An immunochemical characterization of the phytochrome destruction reaction. Biochim Biophys Acta. 1974 Sep 13;365(1):93–107. doi: 10.1016/0005-2795(74)90253-0. [DOI] [PubMed] [Google Scholar]
- Quail P. H., Briggs W. R. Irradiation-enhanced Phytochrome Pelletability: Requirement for Phosphorylative Energy in Vivo. Plant Physiol. 1978 Nov;62(5):773–778. doi: 10.1104/pp.62.5.773. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Quail P. H., Schäfer E., Marmé D. Turnover of phytochrome in pumpkin cotyledons. Plant Physiol. 1973 Aug;52(2):128–131. doi: 10.1104/pp.52.2.128. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schäfer E., Lassig T. U., Schopfer P. Photocontrol of phytochrome destruction in grass seedlings. The influence of wavelength and irradiance. Photochem Photobiol. 1975 Nov;22(5):193–202. doi: 10.1111/j.1751-1097.1975.tb06736.x. [DOI] [PubMed] [Google Scholar]
- Stone H. J., Pratt L. H. Phytochrome destruction: apparent inhibition by ethylene. Plant Physiol. 1978 Dec;62(6):922–923. doi: 10.1104/pp.62.6.922. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Theologis A., Ray P. M. Early auxin-regulated polyadenylylated mRNA sequences in pea stem tissue. Proc Natl Acad Sci U S A. 1982 Jan;79(2):418–421. doi: 10.1073/pnas.79.2.418. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vierstra R. D., Quail P. H. Native phytochrome: Inhibition of proteolysis yields a homogeneous monomer of 124 kilodaltons from Avena. Proc Natl Acad Sci U S A. 1982 Sep;79(17):5272–5276. doi: 10.1073/pnas.79.17.5272. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Walker J. C., Key J. L. Isolation of cloned cDNAs to auxin-responsive poly(A)RNAs of elongating soybean hypocotyl. Proc Natl Acad Sci U S A. 1982 Dec;79(23):7185–7189. doi: 10.1073/pnas.79.23.7185. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zurfluh L. L., Guilfoyle T. J. Auxin-induced changes in the population of translatable messenger RNA in elongating sections of soybean hypocotyl. Plant Physiol. 1982 Feb;69(2):332–337. doi: 10.1104/pp.69.2.332. [DOI] [PMC free article] [PubMed] [Google Scholar]


