Sequence specific purification of a particular tRNA by solid phase DNA probe.

A novel method for the purification of a specific tRNA using solid phase DNA probe is developed. With this method, the probe DNA immobilized on HPLC gel hybridized with target tRNA within a minute at room temperature. The hybridizing capacity of the solid phase probe was about 20 O.D. per gram dry gel when yeast phenylalanine tRNA was used. The specificity of this method was extremely high and the recovery rate was about 90%.     

A highly sensitive and accurate gene expression analysis by sequencing (“bead-seq”) for a single cell

Analyses of gene expressions in single cells are important for understanding detailed biological phenomena. Here, a highly sensitive and accurate method by sequencing (called “bead-seq”) to obtain a whole gene expression profile for a single cell is proposed. A key feature of the method is to use a complementary DNA (cDNA) library on magnetic beads, which enables adding washing steps to remove residual reagents in a sample preparation process. By adding the washing steps, the next steps can be carried out under the optimal conditions without losing cDNAs. Error sources were carefully evaluated to conclude that the first several steps were the key steps. It is demonstrated that bead-seq is superior to the conventional methods for single-cell gene expression analyses in terms of reproducibility, quantitative accuracy, and biases caused during sample preparation and sequencing processes.