A<unk> <unk>  is any RNA molecule that is not translated into a protein. A previously used synonym, particularly with bacteria, was small RNA (sRNA). However, some<unk> s are very large (e.g. Xist). Less-frequently used synonyms are<unk> -messenger RNA <unk> , small<unk> -messenger RNA (snmRNA), or functional RNA (fRNA).  The DNA sequence from which a<unk>  is transcribed as the end product is often called an RNA gene or<unk>  gene (see gene).<unk>  genes include transfer RNA (tRNA) and ribosomal RNA (rRNA), small RNAs such as snoRNAs, microRNAs, siRNAs and piRNAs and lastly long<unk> s that include  examples such as Xist, Evf, Air, CTN and PINK. The number of<unk> s encoded within the genome is unknown, however recent transcriptomic and microarray studies suggest the existence of over 30,000 long<unk> s and at least as many small regulatory RNAs within the mouse genome alone. Since most of the newly identified<unk> s have not been validated for their function, it is possible that majority of them is meaningless (e.g.<unk> -functional or truncated transcript).
One of the major findings of the 2007 ENCODE Pilot Project was that "nearly the entire genome may be represented in primary transcripts that extensively overlap and include many<unk> -protein-coding regions."
Non-coding RNA
Viral vector
Transfer RNA
Capsid
Nucleic acid
Viral envelope
Precursor mRNA
Transposon