PAH-modulating compositions and methods
The disclosure provides, e.g., compositions, systems, and methods for targeting, editing, modifying, or manipulating a host cell's genome at one or more locations in a DNA sequence in a cell, tissue, or subject. Gene modifying systems for treating phenylketonuria (PKU) are described.
1 . A template RNA comprising, from 5′ to 3′:
a) a gRNA spacer that is complementary to a first portion of a human PAH gene, wherein the gRNA spacer comprises an RNA sequence of nucleotides 1 to 20 of SEQ ID NO: 37,221;
b) a gRNA scaffold that binds a SpyCas9 domain;
c) a heterologous object sequence comprising a mutation region to correct a mutation in a second portion of the human PAH gene, wherein the heterologous object sequence comprises a nucleotide sequence of nucleotides 97 to 105 of SEQ ID NO: 37,221; and
d) a primer binding site (PBS) sequence comprising at least 3 bases with 100% identity to a third portion of the human PAH gene, wherein the PBS sequence comprises a nucleotide sequence of nucleotides 106 to 116 of SEQ ID NO: 37,221.
2 . The template RNA of claim 1 , wherein the mutation to be corrected in the human PAH gene is R408W.
3 . The template RNA of claim 1 , wherein the gRNA spacer has a length of 20 nucleotides.
4 . The template RNA of claim 1 , wherein the heterologous object sequence has a length of 9-16 nucleotides.
5 . The template RNA of claim 1 , wherein the heterologous object sequence comprises, from 5′ to 3′, a post-edit homology region, a mutation region, and a pre-edit homology region.
6 . The template RNA of claim 1 , wherein the heterologous object sequence consists of an RNA sequence of GGGCCGAGG.
7 . The template RNA of claim 1 , wherein the PBS sequence has a length of 11-12 nucleotides.
8 . The template RNA of claim 1 , wherein the PBS sequence consists of an RNA sequence of 106 to 116 of SEO ID NO: 37,221.
9 . The template RNA of claim 1 , wherein the gRNA scaffold comprises an RNA sequence having at least 90% identity to nucleotides 21 to 96 of SEQ ID NO: 37,221.
10 . The template RNA of claim 1 , wherein the gRNA scaffold comprises an RNA sequence of nucleotides 21 to 96 of SEQ ID NO: 37,221.
11 . The template RNA of claim 1 , which comprises an RNA sequence having at least 90% identity to SEQ ID NO: 37,221.
12 . The template RNA of claim 1 , which comprises an RNA sequence of SEQ ID NO: 37,221.
13 . The template RNA of claim 1 , which comprises one or more chemically modified nucleotides.
14 . The template RNA of claim 13 , which comprises the RNA sequence and chemical modifications of SEQ ID NO: 30,500.
15 . A gene modifying system comprising:
a template RNA of claim 1 , and
a gene modifying polypeptide comprising a SpyCas9 nickase domain, or a nucleic acid encoding the gene modifying polypeptide.
16 . The gene modifying system of claim 15 , which comprises the nucleic acid encoding the gene modifying polypeptide, wherein the nucleic acid comprises RNA.
17 . The gene modifying system of claim 15 , wherein the gene modifying polypeptide comprises:
a reverse transcriptase (RT) domain;
a SpyCas9 nickase domain; and
a linker disposed between the RT domain and the SpyCas9 nickase domain.
18 . The gene modifying system of claim 17 , wherein the RT domain is an RT domain from a murine leukemia virus (MMLV), a porcine endogenous retrovirus (PERV), an Avian reticuloendotheliosis virus (AVIRE), a feline leukemia virus (FLV), a simian foamy virus (SFV), a bovine leukemia virus (BLV), a Mason-Pfizer monkey virus (MPMV), a human foamy virus (HFV), or a bovine foamy/syncytial virus (BFV/BSV).
19 . The gene modifying system of claim 18 , wherein the simian foamy virus is a SFV3L.
20 . The gene modifying system of claim 17 , which further comprises a second strand-targeting gRNA spacer that directs a second nick to a second strand of the human PAH gene.
21 . A pharmaceutical composition, comprising the gene modifying system of claim 15 and a pharmaceutically acceptable excipient or carrier.
22 . The pharmaceutical composition of claim 21 , wherein the pharmaceutically acceptable excipient or carrier is selected from the group consisting of a plasmid vector, a viral vector, a vesicle, and a lipid nanoparticle.
23 . A method for modifying a target site in the human PAH gene in a cell, the method comprising contacting the cell with the gene modifying system of claim 15 , or DNA encoding the same, thereby modifying the target site in the human PAH gene in a cell.
24 . A method for treating a subject having phenylketonuria (PKU) or hyperphenylalaninemia, the method comprising administering to the subject the gene modifying system of claim 15 thereby treating the subject havingPKU or hyperphenylalaninemia.
25 . A method of making the template RNA of claim 1 , the method comprising synthesizing the template RNA by in vitro transcription, solid-phase synthesis, or by introducing a DNA encoding the template RNA into a host cell under conditions that allow for production of the template RNA.
26 . A template RNA comprising a sequence having at least 90% identity to SEQ ID NO: 37221.
27 . The template RNA of claim 26 , which comprises a sequence having at least 95% identity to SEQ ID NO: 37221.
28 . The template RNA of claim 26 , which comprises a sequence having at least 99% identity to SEQ ID NO: 37221.