Growth arrest-specific 5 is a non-protein coding

RNA Ribonucleic acid (RNA) is a polymeric molecule that is essential for most biological functions, either by performing the function itself (non-coding RNA) or by forming a template for the production of proteins (messenger RNA). RNA and deoxyrib ...

that in humans is encoded by the GAS5

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

. GAS5

noncoding RNA A non-coding RNA (ncRNA) is a functional RNA molecule that is not translated into a protein. The DNA sequence from which a functional non-coding RNA is transcribed is often called an RNA gene. Abundant and functionally important types of non-co ...

, which accumulates in growth arrested cells, acts as a decoy hormone response element for the

glucocorticoid receptor The glucocorticoid receptor (GR or GCR) also known by its gene name ''NR3C1'' ( nuclear receptor subfamily 3, group C, member 1) is the steroid receptor for glucocorticoids such as cortisol. The GR is expressed in almost every cell in the bod ...

(GR) and hence blocks the upregulation of gene expression by activated GR. A number of studies have linked GAS5 to

apoptosis Apoptosis (from ) is a form of programmed cell death that occurs in multicellular organisms and in some eukaryotic, single-celled microorganisms such as yeast. Biochemistry, Biochemical events lead to characteristic cell changes (Morphology (biol ...

and it may play a role in the progression of some types of

cancer Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...

. The GAS5 introns host several snoRNA sequences, including SNORD81, SNORD47, SNORD80, SNORD79, SNORD78, SNORD44, SNORD77, SNORD76, SNORD75 and SNORD74. These intronic sequences are more conserved than the exons of the host gene, these sorts of genes are often called "inside-out genes". It was recently discovered that the nonsense-mediated degradation pathway can regulate the function of the GAS5 in mammalian cells.

References

Further reading