Methods for treating viral infections

A nucleic acid construct comprising, in 5′ to 3′ order:

• (a) a start codon;
• (b) the nucleic acid residues of exon 7 of SMN, wherein any number of nucleotides are inserted after the 48th nucleotide residue from the 5′ end of exon 7 of SMN as long as the native stop codon of exon 7 of SMN is inactivated and any additional stop codon is not generated;
• (c) a fragment of the nucleic acid residues of exon 8 of SMN;
• and (d) a reporter gene coding sequence lacking a start codon, wherein:
• (i) the reporter gene coding sequence is fused to the fragment of the nucleic acid residues of exon 8 of SMN such that the first codon of the reporter gene coding sequence and the first codon of the fragment are out of frame with each other in the mRNA transcript transcribed from the nucleic acid construct and there is a stop codon upstream of the reporter gene coding sequence in the region of the mRNA transcript that corresponds to the fragment of the nucleic acid residues of exon 8 of SMN;
• and (ii) the first start codon and the stop codon upstream from the reporter gene coding sequence in the mRNA transcript are in the same contiguous open reading frame without any interruption.

A nucleic acid construct comprising, in 5′ to 3′ order:

• (a) a start codon;
• (b) the nucleic acid residues of exon 7 of SMN, wherein a single guanine residue is inserted after the 48th nucleotide residue from the 5′ end of exon 7 of SMN;
• (c) the nucleic acid residues of intron 7 of SMN or a fragment thereof, wherein the fragment of the nucleic acid residues of intron 7 comprises any number of nucleotides of intron 7 of SMN required for a functional, minimum intron;
• (d) a fragment of the nucleic acid residues of exon 8 of SMN;
• and (e) a reporter gene coding sequence lacking a start codon, wherein:
• (i) the reporter gene coding sequence is fused to the fragment of the nucleic acid residues of exon 8 of SMN such that the first codon of the reporter gene coding sequence and the first codon of the fragment are out of frame with each other in the mRNA transcript transcribed from the nucleic acid construct;
• and (ii) the production of the mRNA transcript generates a stop codon upstream from the reporter gene coding sequence in the region of the mRNA transcript that corresponds to the fragment of the nucleic acid residues of exon SMN;
• and (iii) the first start codon and the stop codon upstream from the reporter gene coding sequence in the mRNA transcript are in the same contiguous open reading frame without any interruption.

A nucleic acid construct comprising, in 5′ to 3′ order:

• (a) a start codon;
• (b) a minimum of one nucleotide;
• (c) (i) a fragment of the nucleic acid residues of exon 7 of SMN, wherein the fragment of the nucleic acid residues of exon 7 of SAN comprises a minimum of the first six nucleotides from the 3″ end of exon 7 of SMN and wherein a single guanine residue is inserted into the fragment of the nucleic acid residues of exon 7 of SMN at the location that corresponds to the location in exon 7 of SMN that is after the 48th nucleotide from the 5′ end of exon 7 of SMN;
• or
• (ii) a fragment of the nucleic acid residues of exon 7 of SMN, wherein the fragment of the nucleic acid residues of exon 7 of SMN consists of the first six nucleotides from the 3′ end of exon 7 of SMN and wherein a single guanine residue is inserted upstream (5′) of the fragment of the nucleic acid residues of exon 7 of SMN;
• (d) the nucleic acid residues of intron 7 of SMN or a fragment thereof, wherein the fragment of the nucleic acid residues of intron 7 of SMN comprises any number of nucleotides of intron 7 required for a functional, minimum intron;
• (e) a fragment of the nucleic acid residues of exon 8 of SMN;
• and
• (f) a reporter gene coding sequence lacking a start codon,
• wherein:
• (i) the reporter gene coding sequence is fused to the fragment of the nucleic acid residues of exon 8 of SMN such that the first codon of the reporter gene coding sequence and the first codon of the fragment are out of frame with each other in the mRNA transcript transcribed from the nucleic acid construct;
• and (ii) the production of the mRNA transcript generates a stop codon upstream from the reporter gene coding sequence in the region of the mRNA transcript that corresponds to the fragment of the nucleic acid residues of exon 8 of SMN;
• and (iii) the first start codon and the stop codon upstream from the reporter gene coding sequence in the mRNA transcript are in the same contiguous open reading frame without any interruption.

A method for reducing or inhibiting a viral infection, comprising contacting a compound with either a cell containing a virus or provirus that employs programmed ribosomal frameshifting, or a mixture of a cell or a population of cells and a virus that employs programmed ribosomal frameshifting, wherein the compound in vitro or in cells increases the amount or activity of a fusion protein encoded by a nucleic acid construct or translated from a RNA transcript transcribed from the nucleic acid construct, and wherein the nucleic acid construct comprises, in 5′ to 3′ order:

• (i) the nucleic acid residues of exon 6 of SMN;
• (ii) the nucleic acid residues of intron 6 of SMN;
• (iii) the nucleic acid residues of exon 7 of SMN, wherein a single guanine is inserted after the 48th nucleotide residue from the 5′ end of exon 7 of SMN;
• (iv) the nucleic acid residues of intron 7 of SMN;
• (v) a fragment of the nucleic acid residues of exon 8 of SMN, wherein the fragment is composed of the first 23 nucleotides from the 5′ end of exon 8 of SMN;
• and (vi) a reporter gene lacking a start codon, wherein the reporter gene is fused to the fragment of the nucleic acid residues of exon 8 of SMN such that the reporter gene and the fragment are out of frame with each other in the mRNA transcript transcribed from the nucleic acid construct, and wherein the production of the mRNA transcript generates a stop codon in the region of the mRNA transcript that corresponds to the fragment of the nucleic acid residues of exon 8 of SMN.

A method for inhibiting or reducing viral titers, viral replication, or viral infectivity in a subject, comprising administering to a subject in need thereof an effective amount of a compound or pharmaceutical composition thereof, wherein the compound modulates the efficiency of programmed ribosomal frameshifting as measured in vitro or in cells by an increase in the amount or activity of a fusion protein encoded by a nucleic acid construct or translated from a RNA transcript transcribed from the nucleic acid construct, and wherein the nucleic acid construct comprises, in 5′ to 3′ order:

• (i) the nucleic acid residues of exon 6 of SMN;
• (ii) the nucleic acid residues of intron 6 of SMN;
• (iii) the nucleic acid residues of exon 7 of SMN, wherein a single guanine is inserted after the 48th nucleotide residue from the 5′ end of exon 7 of SMN;
• (iv) the nucleic acid residues of intron 7 of SMN;
• (v) a fragment of the nucleic acid residues of exon 8 of SMN, wherein the fragment is composed of the first 23 nucleotides from the 5′ end of exon 8 of SMN;
• and (vi) a reporter gene lacking a start codon, wherein the reporter gene is fused to the fragment of the nucleic acid residues of exon 8 of SMN such that the reporter gene and the fragment are out of frame with each other in the mRNA transcript transcribed from the nucleic acid construct, and wherein the production of the mRNA transcript generates a stop codon in the region of the mRNA transcript that corresponds to the fragment of the nucleic acid residues of exon 8 of SMN.

A method for treating a viral infection in a subject or preventing or treating a viral disease in a subject, comprising administering to a subject in need thereof an effective amount of a compound or pharmaceutical composition thereof, wherein the compound modulates the efficiency of programmed ribosomal frameshifting as measured in vitro or in cells by an increase in the amount or activity of a fusion protein encoded by a nucleic acid construct or translated from a RNA transcript transcribed from the nucleic acid construct, and wherein the nucleic acid construct comprises, in 5′ to 3′ order:

• (i) the nucleic acid residues of exon 6 of SMN;
• (ii) the nucleic acid residues of intron 6 of SMN;
• (iii) the nucleic acid residues of exon 7 of SMN, wherein a single guanine is inserted after the 48th nucleotide residue from the 5′ end of exon 7 of SMN;
• (iv) the nucleic acid residues of intron 7 of SMN;
• (v) a fragment of the nucleic acid residues of exon 8 of SMN, wherein the fragment is composed of the first 23 nucleotides from the 5′ end of exon 8 of SMN;
• and (vi) a reporter gene lacking a start codon, wherein the reporter gene is fused to the fragment of the nucleic acid residues of exon 8 of SMN such that the reporter gene and the fragment are out of frame with each other in the mRNA transcript transcribed from the nucleic acid construct, and wherein the production of the mRNA transcript generates a stop codon in the region of the mRNA transcript that corresponds to the fragment of the nucleic acid residues of exon 8 of SAN.