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. 1988 Jan;86(1):208–215. doi: 10.1104/pp.86.1.208

ABA-Regulation of Two Classes of Embryo-Specific Sequences in Mature Wheat Embryos 1

John D Williamson 1,2, Ralph S Quatrano 1,3
PMCID: PMC1054456  PMID: 16665868

Abstract

We have previously described the isolation and characterization of ABA-enhanced sequences from developing wheat embryos. Here we use in vivo RNA labeling and the inhibitors α-amanitin and cycloheximide to determine the level at which ABA acts to modulate these sequences in cultured mature embryos. Sequences fell into two classes: one, represented by the 7S globulin clone, p511, appears to be regulated at the level of transcription, while the other, represented by the early methionine-labeled polypeptide (Em)-protein clone, p1015, has an additional posttranscriptional component. In mature embryos cultured in the absence of ABA, mRNA levels of p511 and p1015 declined rapidly until neither was detected at 3 days postimbibition. Levels of p511 increased in mature embryos cultured in the presence of ABA, but remained low in the presence of ABA + α-amanitin, suggesting p511 RNA is regulated at the level of transcription. Levels of p1015, in contrast, remained high not only in the presence of ABA, but also in the presence of ABA + α-amanitin or α-amanitin alone. This suggests p1015 regulation might be at the level of selective RNA stability. Cycloheximide had no detectable effect on ABA-mediated stabilization of p1015, suggesting that newly synthesized proteins are not involved. Em-protein synthesis rates closely paralleled Em RNA levels, suggesting Em expression is not controlled at the level of translation.

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Selected References

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  1. Ajtkhozhin M. A., Doschanov K. J., Akhanov A. U. Informosomes as a stored form of mRNA in wheat embryos. FEBS Lett. 1976 Jul 1;66(1):124–126. doi: 10.1016/0014-5793(76)80600-x. [DOI] [PubMed] [Google Scholar]
  2. Brooker J. D., Tomaszewski M., Marcus A. Preformed Messenger RNAs and Early Wheat Embryo Germination. Plant Physiol. 1978 Feb;61(2):145–149. doi: 10.1104/pp.61.2.145. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Chen D., Osborne D. J. Hormones in the translational control of early germination in wheat embryos. Nature. 1970 Jun 20;226(5251):1157–1160. doi: 10.1038/2261157a0. [DOI] [PubMed] [Google Scholar]
  4. Cuming A. C. Developmental regulation of gene expression in wheat embryos. Molecular cloning of a DNA sequence encoding the early-methionine-labelled (Em) polypeptide. Eur J Biochem. 1984 Dec 3;145(2):351–357. doi: 10.1111/j.1432-1033.1984.tb08561.x. [DOI] [PubMed] [Google Scholar]
  5. Gerlach W. L., Bedbrook J. R. Cloning and characterization of ribosomal RNA genes from wheat and barley. Nucleic Acids Res. 1979 Dec 11;7(7):1869–1885. doi: 10.1093/nar/7.7.1869. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Jendrisak J. The use of alpha-amanitin to inhibit in vivo RNA synthesis and germination in wheat embryos. J Biol Chem. 1980 Sep 25;255(18):8529–8533. [PubMed] [Google Scholar]
  7. Key J. L., Lin C. Y., Chen Y. M. Heat shock proteins of higher plants. Proc Natl Acad Sci U S A. 1981 Jun;78(6):3526–3530. doi: 10.1073/pnas.78.6.3526. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Peumans W. J., Stinissen H. M. Gramineae lectins: occurrence, molecular biology and physiological function. Prog Clin Biol Res. 1983;138:99–116. [PubMed] [Google Scholar]
  9. Quatrano R. S., Hopkins R., Raikhel N. V. Control of the synthesis and localization of wheat germ agglutinin during embryogenesis. Prog Clin Biol Res. 1983;138:117–130. [PubMed] [Google Scholar]
  10. Scott M. P., Pardue M. L. Translational control in lysates of Drosophila melanogaster cells. Proc Natl Acad Sci U S A. 1981 Jun;78(6):3353–3357. doi: 10.1073/pnas.78.6.3353. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Stuchly S. S., Barski M., Tam B., Hartsgrove G., Symons S. Computer-based scanning system for electromagnetic dosimetry. Rev Sci Instrum. 1983 Nov;54(11):1547–1550. doi: 10.1063/1.1137294. [DOI] [PubMed] [Google Scholar]
  12. Triplett B. A., Quatrano R. S. Timing, localization, and control of wheat germ agglutinin synthesis in developing wheat embryos. Dev Biol. 1982 Jun;91(2):491–496. doi: 10.1016/0012-1606(82)90057-4. [DOI] [PubMed] [Google Scholar]
  13. Vannice J. L., Taylor J. M., Ringold G. M. Glucocorticoid-mediated induction of alpha 1-acid glycoprotein: evidence for hormone-regulated RNA processing. Proc Natl Acad Sci U S A. 1984 Jul;81(14):4241–4245. doi: 10.1073/pnas.81.14.4241. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Walbot V. RNA metabolism during embryo development and germination of Phaseolus vulgaris. Dev Biol. 1971 Nov;26(3):369–379. doi: 10.1016/0012-1606(71)90069-8. [DOI] [PubMed] [Google Scholar]
  15. Williamson J. D., Quatrano R. S., Cuming A. C. Em polypeptide and its messenger RNA levels are modulated by abscisic acid during embryogenesis in wheat. Eur J Biochem. 1985 Oct 15;152(2):501–507. doi: 10.1111/j.1432-1033.1985.tb09224.x. [DOI] [PubMed] [Google Scholar]
  16. de Jiménez E. S., Aguilar R. Protein synthesis patterns : relevance of old and new messenger RNA in germinating maize embryos. Plant Physiol. 1984 May;75(1):231–234. doi: 10.1104/pp.75.1.231. [DOI] [PMC free article] [PubMed] [Google Scholar]

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