Phosphoroselenoate RNA (PSe-RNA) is nuclease resistant and has great potentials in X-ray crystal structure and function studies of noncoding RNAs and protein-RNA interactions. In order to conveniently synthesize PSe-RNA via transcription, we have developed a one-pot synthetic method for the nucleoside 59-(a-P-seleno)-triphosphates (NTPaSe) analogs without protecting any functionality of the ribonucleosides. The NTPaSe diastereomers have been purified, fully characterized, and incorporated into RNAs by T7 RNA polymerase. The transcribed RNAs are diastereomerically pure, and the Se-derivatized ribozymes are generally active. Furthermore, we have established an affinity purification strategy by using immobilized boronate to conveniently purify NTPaSe analogs. Though the affinity-purified NTPaSe analogs are diastereomeric mixtures, they can be directly used in transcription without a significant impact on the transcription efficiency. Moreover, we found that the PSenucleotide is stable during polyacrylamide gel purification, indicating that the PSe-RNAs can be purified straightforwardly for crystal structural and functional studies.

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We have developed a simple method to synthesize 6-seleno-2′-deoxyguanosine (Se dG) by selectively replacing the 6-oxygen atom with selenium. This selenium-atom-specific modification (SAM) alters the optical properties of the naturally occurring 2′-deoxyguanosine (dG). Unlike the native dG, the UVabsorption of Se dG is significantly influenced by the pH of the aqueous solution. Moreover, Se dG is fluorescent at the physiological pH and exhibits pH-dependent fluorescence in aqueous solutions. Furthermore, Se dG has noticeable fluorescence in non-aqueous solutions, indicating its sensitivity to environmental changes. This is the first time a fluorescent nucleoside by single-atom alteration has been observed. Fluorescent nucleosides modified by a single atom have great potential as molecular probes with minimal perturbations to investigate nucleoside interactions with proteins, such as membrane-transporter proteins.

Next-generation sequencing has revolutionized the diagnostic process, making broadscale testing affordable and applicable to almost all specialties; however, there remain several challenges in its widespread implementation. Barriers such as lack of infrastructure or expertise within local health systems and complex result interpretation or counseling make it harder for frontline clinicians to incorporate genomic testing in their existing workflow. The general population is more informed and interested in pursuing genetic testing, and this has been coupled with the increasing accessibility of direct-to-consumer testing. As a result of these changes, primary care physicians and nongenetics specialty providers find themselves seeing patients for whom genetic testing would be beneficial but managing genetic test results that are out of their scope of practice. In this report, we present a practical and centralized approach to providing genomic services through an independent, enterprise-wide clinical service model. We present 4 years of clinical experience, with >3400 referrals, toward designing and implementing the clinical service, maximizing resources, identifying barriers, and improving patient care. We provide a framework that can be implemented at other institutions to support and integrate genomic services across the enterprise.