A mass spectrometry-based method for direct determination of pseudouridine in RNA.

Pseudouridine (5-ribosyluracil, Ψ) is the only 'mass-silent' nucleoside produced by post-transcriptional RNA modification. We describe here a novel mass spectrometry (MS)-based method for direct determination of Ψ in RNA. The method assigns a Ψ-containing nucleolytic RNA fragment by an accurate measurement of a signature doubly dehydrated nucleoside anion ([C9H7N2O4](1-),m/z207.

Identification of putative target genes of bZIP19, a transcription factor essential for Arabidopsis adaptation to Zn deficiency in roots.

Zinc (Zn) depletion adversely affects plant growth. To avoid lethal depletion of cellular Zn, plants have evolved mechanisms to adjust the expression of genes associated with Zn homeostasis, the details of which are poorly understood. In the present study, we isolated an Arabidopsis thaliana T-DNA insertion mutant that exhibited hypersensitivity to Zn depletion.