Open AccessLight regulation of specific mRNA species in Lemna gibba L. G-3
Author(s) -
Elaine M. Tobin
Publication year - 1978
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.75.10.4749
Subject(s) - lemna gibba , ribulose 1,5 bisphosphate , polyadenylation , darkness , immunoprecipitation , protein subunit , biochemistry , biology , translation (biology) , messenger rna , pyruvate carboxylase , protein biosynthesis , rna , rubisco , microbiology and biotechnology , photosynthesis , enzyme , botany , gene , ecology , aquatic plant , macrophyte
Polyadenylated RNA was isolated fromLemna gibba L. G-3 and translated in a cell-free system from wheat germ. When plants were placed into complete darkness for 4 days, then returned to light for 18 hr, increased amounts of polyadenylated mRNA for at least two polypeptides were detected byin vitro translation over those amounts present in the dark. These two polypeptides have molecular weights of 32,000 and 20,000. The 20,000 dalton polypeptide was identified by immunoprecipitation as the precursor to the small subunit of the photosynthetic enzyme ribulose-1,5-bisphosphate carboxylase [3-phospho-D-glycerate carboxy-lyase (dimerizing), EC 4.1.1.39]. The polyadenylated mRNA that codes for the small subunit is not detectable by immunoprecipitation of translation products in the dark-treated tissue. Plants growing in the light actively synthesize both subunits of ribulose-1,5-bisphosphate carboxylase, but synthesis of these proteins was found to be greatly diminished in plants placed in darkness for 4 days. These results indicate that white light can dramatically affect the steady-state levels of specific polyadenylated mRNAs.