The Cas9 nuclease and requirements for RNA-guided genome-editing. Cas9 is the nuclease guided by the crRNA and tracrRNA (or trans-activating crRNA) to cleave specific DNA sequences (Deltcheva et al.2011). A guide RNA (gRNA) can be designed to include a hairpin that mimics the tracrRNA-crRNA complex (Jinek et al. 2012).he Cas9 nuclease and requirements for RNA-guided genome-editing. Cas9 is the nuclease guided by the crRNA and tracrRNA (or trans-activating crRNA) to cleave specific DNA sequences (Deltcheva et al. 2011).
Solid Surface Bathroom Countertops: These countertops are made from synthetic materials, so they are manufactured in many colors and styles. The pros of solid surface countertops include the choices, strength and a non-porous surface that cleans up quickly.
Concrete, the humble material behind many a building foundation, makes for nearly indestructible kitchen counters and offers artisan-crafted customization in both color and layout. With these bragging rights, concrete rises above much of the countertop competition. Learn more below and see whether concrete counters are right for your kitchen. The basics: Concrete is composed of water, a binder and a filler. 1  The binder, cement, is most commonly Portland cement, but slag cement and fly ash â both industrial waste by-products â are becoming common additions. 2  The filler, an aggregate, can be anything from sand, gravel and stone to crushed glass and beads.