lincRNA

LincRNA stands for long intergenic non-coding RNA. These are RNA transcripts longer than about 200 nucleotides that originate from genomic regions located between protein-coding genes and do not overlap annotated genes on either strand.

Most lincRNAs are transcribed by RNA polymerase II, capped at the 5' end, polyadenylated, and spliced. They tend to be less conserved at the sequence level than protein-coding genes, often show tissue- or cell-type–specific expression, and can be predominantly nuclear or cytoplasmic.

Functional roles are diverse. LincRNAs can act as scaffolds to assemble ribonucleoprotein complexes, guides to recruit chromatin-modifying enzymes to target loci, decoys to sequester transcription factors or microRNAs, or enhancers that influence neighboring gene activity. Some regulate transcription in cis, others affect distant genes in trans.

Genomic and evolutionary properties: generally low sequence conservation, rapid turnover, and high species specificity in many cases; many are expressed at low levels.

Biological and clinical relevance: lincRNAs participate in development, imprinting, and disease, including cancer. Their functions are inferred from expression patterns, knockdown or knockout studies, and molecular interaction data, but many lincRNAs remain uncharacterized.