Highly Sensitive Fluorescence Detection of Daptomycin in Murine Samples through Derivatization with 2,3-Naphthalenedialdehyde.

A highly sensitive high-performance liquid chromatography method has been developed using the pre-column fluorescent derivatization of daptomycin (DAP) through cyclization of the amino group of ornithine with 2,3-naphthalenedialdehyde. With the proposed method, the limits of detection and quantification of DAP in murine serum were 8 and 3 nmol/L, respectively, and the calibration curve was linear across the examined dynamic range from 8 nmol/L to 1 µmol/L (n = 8, r = 0.9986). This method is suitable for animal experiments examining the side effects of DAP therapy using mice as a simple method with quantification to the order of 10 nmol/L.

Transcription activator-like effector nucleases efficiently disrupt the target gene in Iberian ribbed newts (Pleurodeles waltl), an experimental model animal for regeneration.

Regeneration of a lost tissue in an animal is an important issue. Although regenerative studies have a history of research spanning more than a century, the gene functions underlying regulation of the regeneration are mostly unclear. Analysis of knockout animals is a very powerful tool with which to elucidate gene function. Recently, transcription activator-like effector nucleases (TALENs) have been developed as an effective technique for genome editing. This technique enables gene targeting in amphibians such as newts that were previously impossible. Here we show that newts microinjected with TALEN mRNAs designed for targeting the tyrosinase gene in single-cell stage embryos revealed an albino phenotype. Sequence analysis revealed that the tyrosinase genes were effectively disrupted in these albino newts. Moreover, precise genome alteration was achieved using TALENs and single strand oligodeoxyribonucleotides. Our results suggest that TALENs are powerful tools for genome editing for regenerative research in newts.