The present invention relates to a virus-derived particle comprising one or more Cas protein(s), as well as to kits and methods using the same for altering a target nucleic acid.

The present invention relates to a virus-derived particle comprising one or more Cas protein(s), as well as to kits and methods using the same for altering a target nucleic acid.

The present invention relates to a virus-derived particle comprising one or more Cas protein(s), as well as to kits and methods using the same for altering a target nucleic acid.

Embodiments disclosed herein are directed to engineered CRISPR-Cas effector proteins that comprise at least one modification compared to an unmodified CRISPR-Cas effector protein that enhances binding of the CRISPR complex to the binding site and/or alters editing preference as compared to wild type. In certain example embodiments, the CRISPR-Cas effector protein is a Type V effector protein. In certain other example embodiments, the Type V effector protein is Cpf1. Embodiments disclosed herein are directed to viral vectors for delivery of CRISPR-Cas effector proteins, including Cpf1. In certain example embodiments, the vectors are designed so as to allow packaging of the CRISPR-Cas effector protein within a single vector. There is also an increased interest in the design of compact promoters for packing and thus expressing larger transgenes for targeted delivery and tissue-specificity. Thus, in another aspect certain embodiments disclosed herein are directed to delivery vectors, constructs, and methods of delivering larger genes for systemic delivery.