ABSTRACT
By solid-state reaction and doping, a series of red-emitting phosphors Na(x)Y(0.92-x/3)(MoO(4))(y)(WO(4))(1-y)O(0.5) : zEu(3+) have been synthesized. Through optimization of the process conditions and photoluminescent analysis, one type of red emission is obtained that matches nicely with ultraviolet light-emitting diode (UV-LED) chips.
ABSTRACT
The Arabidopsis thaliana lysyl tRNA synthetase (AtKRS) structurally and functionally resembles the well-characterized prokaryotic class IIb KRS, including the propensity to aminoacylate tRNA(Lys) with suboptimal identity elements, as well as non-cognate tRNAs. Transient expression of AtKRS in carrot cells promotes aminoacylation of such tRNAs in vivo and translational recoding of lysine at nonsense codons. Stable expression of AtKRS in Zea mays causes translational recoding of lysine into zeins, significantly enriching the lysine content of grain.
Subject(s)
Arabidopsis/enzymology , Lysine-tRNA Ligase/genetics , Lysine/genetics , RNA, Transfer, Lys/metabolism , Acylation , Amino Acid Sequence , Base Sequence , Blotting, Southern , DNA Primers , Molecular Sequence Data , RNA, Transfer, Lys/genetics , Zea mays/enzymologyABSTRACT
Bombardment of a highly expressed dicot tRNA(ala)(GAC) gene into Zea mays bz-E2 or bz-E5 coleoptiles causes suppression of an Ala(458 )-->Val missense mutation, visualized by the development of anthocyanin pigment. Missense suppression is blocked by mutation of tRNA(ala)(GAC) at a site that prevents aminoacylation by the dicot alanyl-tRNA synthetase, indicating that features identified for expression and utilization of dicot tRNAs also function in monocots. This assay of the expression and utilization of tRNA(ala)(GAC) also can be used to study a variety of tRNAs and their genes, most of which can be relatively easily altered to be charged by alanyl tRNA synthetase.
Subject(s)
Gene Expression Regulation, Plant/genetics , Mutation, Missense/genetics , Plant Proteins/genetics , RNA, Transfer, Ala/genetics , Suppression, Genetic/genetics , Zea mays/genetics , Cotyledon/genetics , Genetic Techniques , RNA, Plant/genetics , RNA, Plant/metabolismABSTRACT
The world's major crops are deficient in lysine and several other amino acids essential for human and animal nutrition. Increasing the content of these amino acids in cereals, our major source of dietary energy, can help feed a global population whose reliance upon dietary protein is growing faster than crop yields. Here we document the heritable expression in rice, the world's major cereal crop, of tRNA(lys) species that introduce lysine at alternative codons during protein synthesis, resulting in a significant enrichment of the lysine content of proteins in rice seeds without changing the types or quantities of the seed storage proteins.