Vedabio, Inc.

University of Illinois

Labsimply, Inc.

Ashish Pandey

Anurup Ganguli

Jacob Berger

Ariana Mostafa

Rashid Bashir

Andrew Garst

Presented is a nucleic acid-guided nuclease cascade assay that can detect one or more target nucleic acids of interest of interest without the need for amplifying the target nucleic acids of interest. The nucleic acid-guided nuclease cascade assays utilize signal amplification mechanisms comprising various components including nucleic acid-guided nucleases and guide RNAs (gRNAs) forming ribonucleoprotein complexes, blocked primer molecules, template molecules, polymerases and reporter moieties.

Detection assays

The present disclosure relates to compositions of matter and assay methods used to detect one or more target nucleic acids of interest in a sample. The compositions and methods allow one to control reaction kinetics of the cascade assay by two orders of magnitude via molecular design of one of the reaction components; further, varying molecular design also allows for quantification of target nucleic acids of interest over a large range of concentrations or discriminating between extremely low copy numbers of target nucleic acids of interest.

Tuning cascade assay kinetics via molecular design

The present disclosure relates to compositions of matter and assay methods used to detect one or more target nucleic acids of interest in a sample. The compositions and methods provide signal boost upon detection of target nucleic acids of interest in less than one minute and in some instances instantaneously at ambient temperatures down to 16° C. or less, without amplification of the target nucleic acids yet allowing for massive multiplexing, high accuracy and minimal non-specific signal generation.

Signal boost cascade assay

The present disclosure relates to variant engineered nucleic acid-guided nucleases that may be used in CRISPR-based cascade assay systems to detect one or more target nucleic acids in a sample. The variant nucleases comprise an activity such that double-stranded DNA substrates do not bind to or are not cleaved by variant LbCas12a nuclease, or bind to or are cleaved very slowly by the variant nuclease, however single-stranded DNA substrates can bind and are cleaved by the variant nuclease, and wherein the variant nuclease exhibits both cis- and trans-cleavage activity.

Engineered nucleic acid-guided nucleases

The present disclosure describes compositions of matter comprising a ribonucleoprotein complex comprising a nucleic acid-guided nuclease and a guide RNA, and further comprising a blocking nucleic acid molecule represented by Formula IV, wherein Formula IV in the 5′-to-3′ direction comprises: T-D-M-A-Lp-C; wherein T is 17-31 nucleotides in length; D is 0-15 nucleotides in length; M is 1-25 nucleotides in length; A is 0-15 nucleotides in length and comprises a sequence complementary to D; and L is 3-25 nucleotides in length; p is 0 or 1; C is 4-15 nucleotides in length and comprises a sequence complementary to T; and wherein the blocking nucleic acid molecule comprises a sequence complementary to a gRNA.

Compositions of matter for detection assays

The present disclosure describes compositions of matter comprising a ribonucleoprotein complex comprising a nucleic acid-guided nuclease and a guide RNA, and further comprising and a blocking nucleic acid molecule represented by Formula III in the 5′-to-3′ direction comprises: T-D-M-A-(B-L)-C; wherein T is 17-135 nucleotides in length; D is 0-10 nucleotides in length; M is 1-25 nucleotides in length or is absent, wherein if M is absent then T-D and A-(B-L)-C are separate nucleic acid strands; A is 0-15 nucleotides in length and comprises at least 50% sequence complementarity to D; B is 4-12 nucleotides in length and comprises at least 50% sequence complementarity to T; L is 3-25 nucleotides in length; J is an integer between 1 and 10; C is 4-15 nucleotides in length; and wherein the blocking nucleic acid molecule comprises a sequence complementary to a gRNA.

The present disclosure describes compositions of matter comprising a ribonucleoprotein complex comprising a nucleic acid-guided nuclease and a guide RNA, and further comprising and a blocking nucleic acid molecule represented by Formula I, wherein Formula I in the 5'-to-3&#x2032; direction comprises: A-(B-L)-C-M-T-D; wherein A is 0-15 nucleotides in length; B is 4-12 nucleotides in length; L is 3-25 nucleotides in length; J is an integer between 1 and 10; C is 4-15 nucleotides in length; M is 1-25 nucleotides in length or is absent, wherein if M is absent then A-(B-L)-C and T-D are separate nucleic acid strands; T is 17-135 nucleotides in length and comprises at least 50% sequence complementarity to B and C; D is 0-10 nucleotides in length and comprises at least 50% sequence complementarity to A; and wherein the blocking nucleic acid molecule comprises a sequence complementary to a gRNA.

Growing community of inventors

San Diego, CA, United States of America

Ashish Pandey