A simple and rapid method for enzymatic synthesis of CRISPR-Cas9 sgRNA libraries.

CRISPR-Cas9 sgRNA libraries have transformed functional genetic screening and have enabled several innovative methods that rely on simultaneously targeting numerous genetic loci. Such libraries could be used in a vast number of biological systems and in the development of new technologies, but library generation is hindered by the cost, time, and sequence data required for sgRNA library synthesis. Here, we describe a rapid enzymatic method for generating robust, variant-matched libraries from any source of cDNA in under 3 h. This method, which we have named SLALOM, utilizes a custom sgRNA scaffold sequence and a novel method for detaching oligonucleotides from solid supports by a strand displacing polymerase. With this method, we constructed libraries targeting the E. coli genome and the transcriptome of developing zebrafish hearts, demonstrating its ability to expand the reach of CRISPR technology and facilitate methods requiring custom libraries.

ZeMo: An Open Source Water Quality Monitoring System for Aquaria.

Zebrafish and other aquatic organisms depend on careful monitoring and adjustment of water quality for health and survival. This ideally includes continuous monitoring of several water parameters, including temperature, pH, conductivity, and dissolved oxygen. However, manual readings can be laborious, and commercially available monitors are cost-prohibitive for many installations, especially in small laboratories and classrooms. To address these issues, we have created ZeMo, a high-end open-source water monitoring system that includes a touchscreen, web interface, and email alerts-making continuous water quality monitoring attainable for a wide range of aquarium installations.

A novel bone morphogenetic protein 2 mutant mouse, nBmp2NLS(tm), displays impaired intracellular Ca2+ handling in skeletal muscle.

We recently reported a novel form of BMP2, designated nBMP2, which is translated from an alternative downstream start codon and is localized to the nucleus rather than secreted from the cell. To examine the function of nBMP2 in the nucleus, we engineered a gene-targeted mutant mouse model (nBmp2NLS(tm)) in which nBMP2 cannot be translocated to the nucleus. Immunohistochemistry demonstrated the presence of nBMP2 staining in the myonuclei of wild type but not mutant skeletal muscle. The nBmp2NLS(tm) mouse exhibits altered function of skeletal muscle as demonstrated by a significant increase in the time required for relaxation following a stimulated twitch contraction. Force frequency analysis showed elevated force production in mutant muscles compared to controls from 10 to 60 Hz stimulation frequency, consistent with the mutant muscle's reduced ability to relax between rapidly stimulated contractions. Muscle relaxation after contraction is mediated by the active transport of Ca(2+) from the cytoplasm to the sarcoplasmic reticulum by sarco/endoplasmic reticulum Ca(2+) ATPase (SERCA), and enzyme activity assays revealed that SERCA activity in skeletal muscle from nBmp2NLS(tm) mice was reduced to approximately 80% of wild type. These results suggest that nBMP2 plays a role in the establishment or maintenance of intracellular Ca(2+) transport pathways in skeletal muscle.