Gene expression system using stealthy RNA, and gene introduction/expression vector including said RNA

A stealth RNA which is a negative-sense single-stranded RNA (A), comprising:

• (1) RNA sequences encoding any given protein or functional RNA,
• (2) RNA sequences constituting noncoding region(s) that are unrecognizable by an innate immune system,
• (3) transcription start signal sequences recognized by an RNA-dependent RNA polymerase,
• (4) transcription termination signal sequences recognized by the RNA-dependent RNA polymerase,
• (5) RNA sequences comprising replication origins recognized by the RNA-dependent RNA polymerase,
• (6) RNA sequences encoding the RNA-dependent RNA polymerase and having a structure optimized to be unrecognizable by an innate immune system,
• (7) an RNA sequence encoding a protein that regulates activity of the RNA-dependent RNA polymerase, and having a structure optimized to be unrecognizable by an innate immune system, and
• (8) an RNA sequence encoding a single-stranded RNA binding protein and having a structure optimized to be unrecognizable by an innate immune system,
• wherein the stealth RNA is capable of forming a complex that does not activate an innate immune system together with the single-stranded RNA binding protein (B), and the RNA-dependent RNA polymerase (C),
• wherein the RNA-dependent RNA polymerase encoded by the RNA sequences of the (6) consists of L protein and P protein of an RNA virus belonging to a paramyxovirus family,
• wherein the protein that regulates activity of the RNA-dependent RNA polymerase encoded by the RNA sequence of the (7) is C protein of the RNA virus belonging to the paramyxovirus family,
• wherein the single-stranded RNA binding protein encoded by the RNA sequence of the (8) is NP protein of the RNA virus belonging to the paramyxovirus family,
• wherein the RNA sequences of the (2) are RNA sequences having a length of 5 nucleotides to 49 nucleotides, and are a partial mRNA(s) of an animal gene expressed in animal cells, and
• wherein all of the RNA sequences of the (3) to (5) are RNA sequences comprising a transcription start signal, a transcription termination signal, or a replication origin sequence isolated from a genome of the RNA virus belonging to the paramyxovirus family.