The invention provides a double-stranded ribonucleic acid (dsRNA) having a chain length suitable for simultaneously showing low toxicity and high function in the use of an adjuvant and the like, and resisting variation of chain length even when subjected to a heating and cooling treatment, or a salt thereof; an immune potentiator, adjuvant, pharmaceutical product and the like containing the dsRNA and the like; and a production method of such dsRNA and the like. The invention is characterized in that the weight average chain length of two or more single-stranded ribonucleic acids (ssRNAs) constituting the first chain constituting dsRNA is not more than ½ of the weight average chain length of one ssRNA constituting the second chain.

Nucleic acids (DNA and RNA) provide a versatile platform for engineering synthetic biology in a variety of technology areas including medicine, science, agriculture, and energy. In many settings, degradation of nucleic acid molecules poses a significant engineering challenge as the molecules do not function if they have been degraded. In some embodiments, nucleic acid protective elements (PELs) are used to protect chemically synthesized or expressed nucleic acid molecules from degradation. PELs may be derived from all or part of a viral xrRNA sequence and/or structural motif, PELs may include rationally designed sequences and/or structural motifs, PELs may be engineered using directed evolution, and in some embodiments, PELs comprise a mixture of biologically derived, rationally designed sequence and/or structural motifs, and/or sequences and/or structural motifs that are engineered by directed evolution. In some embodiments, PELs significantly enhance the performance of nucleic acid synthetic biology, protecting nucleic acid regulatory and/or structural elements from degradation to increase regulatory dynamic range, fractional dynamic range, fold-change, and/or other performance metrics. In some embodiments, PELs that reduce nucleic acid degradation provide a platform technology for enhancing the performance of synthetic biology, with applications including therapeutics, diagnostics, biological research tools, vaccines, crop protection, molecular manufacturing, sustainable energy production, and other areas involving nucleic acids.

A hetero-structured RNA with two 3′-overhangs and use thereof as an immune stimulant are provided.

A nucleic acid complex that exhibits an excellent antisense effect in the skeletal muscle and/or heart muscle, and a composition for treating or preventing a muscle disease that develops in the skeletal muscle, heart muscle, and the like having the nucleic acid complex as an active ingredient is disclosed. Also provided is a double-stranded nucleic acid complex in which a first nucleic acid strand that hybridizes to the transcription product of a target gene and has an antisense effect on the transcription product is annealed with a second nucleic acid strand that has a base sequence complementary to the first nucleic acid strand and is bound to cholesterol or analog thereof.

The present invention relates to products and compositions and their uses. In particular the invention relates to nucleic acid products that interfere with the LPA gene expression or inhibit its expression, preferably for use as treatment, prevention or reduction of risk of suffering cardiovascular disease such as coronary heart disease or aortic stenosis or stroke or any other disorder, pathology or syndrome linked to elevated levels of Lp(a) particles.

An object is to provide a technique that can enhance the binding properties of a single-stranded polynucleotide comprising a palindromic structure comprising an acyclic polynucleotide structural unit to target polynucleotides, such as miRNA, while suppressing self-duplex formation of the single-stranded polynucleotide. This object is achieved by a single-stranded polynucleotide comprising a palindromic structure comprising an acyclic polynucleotide structural unit, wherein adenine in the palindromic structure is replaced by diaminopurine, and thymine at a position complementary to the adenine is replaced by a thiouracil derivative.

One aspect of the present invention relates to a small circular interfering RNA (sciRNA) comprising a sense strand and an antisense strand, each of said sense and antisense strands comprising at least one nucleic acid modification, optionally wherein the sense strand has a circular or substantially circular structure. Other aspects of the invention relate a pharmaceutical composition and a method for inhibiting the expression of a target gene in a subject using the sciRNA.

A novel family of human mitochondrial RNAs, referred to as chimeric RNAs, which are differentially expressed in normal, pre-cancer and cancer cells, are described. Oligonucleotides targeted to the chimeric RNAs are provided. The described oligonucleotides or their analogs can be used for cancer diagnostics and cancer therapy as well as for research. In one embodiment of this invention, these oligonucleotides hybridize with the sense or with the antisense mitochondrial chimeric RNAs, and the result of the hybridization is useful to differentiate between normal proliferating cells, pre-cancer cells and cancer cells. In another embodiment of the invention, the compositions comprise oligonucleotides that hybridize with the human chimeric RNAs resulting in cancer cell and pre-cancer cell death, while there is no effect in normal cells, constituting therefore, a novel approach for cancer therapy.

The present invention relates to products and compositions and their uses. In particular the invention relates to nucleic acid products that interfere with the LPA gene expression or inhibit its expression, preferably for use as treatment, prevention or reduction of risk of suffering cardiovascular disease such as coronary heart disease or aortic stenosis or stroke or any other disorder, pathology or syndrome linked to elevated levels of Lp(a) particles.

A method of reducing the level of a transcription product in a cell comprising contacting with the cell a composition comprising a double-stranded nucleic acid complex comprising a first nucleic acid strand annealed to a second nucleic acid strand, wherein: (i) the first nucleic acid strand hybridizes to the transcription product and comprises (a) a region consisting of at least 4 consecutive nucleotides that are recognized by RNase H when the strand is hybridized to the transcription product, (b) one or more nucleotide analogs located on 5′ terminal side of the region, (c) one or more nucleotide analogs located on 3′ terminal side of the region and (d) a total number of nucleotides and nucleotide analogs ranging from 8 to 35 nucleotides and (ii) the second nucleic acid strand comprises (a) nucleotides and optionally nucleotide analogs and (b) at least 4 consecutive RNA nucleotides.