| abstract |
Provided herein are polynucleotides and CRISPR effector proteins that are configured to be covalently linked into a CRISPR complex. A polynucleotide can be further modified to modulate the activity of the CRISPR complex. Modifications of polynucleotides and CRISPR effector proteins can be used to improve the efficacy of target binding and/or cleavage. The invention provides, for example, a CRISPR complex comprising a guide RNA (gRNA) bridged to a CRISPR effector protein at nucleotides in the gRNA, wherein the gRNA comprises a target binding region and a CRISPR effector protein binding region, A CRISPR complex is provided, wherein the nucleotides are outside the target binding region of said gRNA. |