In molecular biology, the 5.8S ribosomal RNA (5.8S rRNA) is a

non-coding RNA A non-coding RNA (ncRNA) is a functional RNA molecule that is not Translation (genetics), 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 im ...

component of the large subunit of the

eukaryotic Eukaryotes () are organisms whose Cell (biology), cells have a cell nucleus, nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the ...

ribosome and so plays an important role in protein translation. It is transcribed by RNA polymerase I as part of the 45S precursor that also contains 18S and

28S rRNA Crazy Eights is a shedding-type card game for two to seven players and the best known American member of the Eights Group which also includes Pig and Spoons. The object of the game is to be the first player to discard all of their cards. The ga ...

. Its function is thought to be in ribosome translocation. It is also known to form

covalent A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs. The stable balance of attractive and repulsive forces between atoms ...

linkage to the

p53 p53, also known as Tumor protein P53, cellular tumor antigen p53 (UniProt name), or transformation-related protein 53 (TRP53) is a regulatory protein that is often mutated in human cancers. The p53 proteins (originally thought to be, and often s ...

tumour suppressor protein. 5.8S rRNA can be used as a reference gene for

miRNA MicroRNA (miRNA) are small, single-stranded, non-coding RNA molecules containing 21 to 23 nucleotides. Found in plants, animals and some viruses, miRNAs are involved in RNA silencing and post-transcriptional regulation of gene expression. miR ...

detection. The 5.8S ribosomal RNA is used to better understand other rRNA processes and pathways in the cell. The 5.8S rRNA is homologous to the 5' end of non-eukaryotic

LSU rRNA Large subunit ribosomal ribonucleic acid (LSU rRNA) is the largest of the two major RNA components of the ribosome. Associated with a number of ribosomal proteins, the LSU rRNA forms the large subunit of the ribosome. The LSU rRNA acts as a rib ...

. In eukaryotes, the insertion of ITS2 breaks LSU rRNA into 5.8S and 28S rRNAs. Some

flies Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced m ...

have their 5.8 rRNA further split into two pieces.

Structure

L567.5 rRNA structure is approximately 150

nucleotides Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules with ...

in size and it consists of plenty of folded strands, some of which are presumed to be single stranded. This ribosomal RNA, along with the 28S and 5S rRNA as well as 46

ribosomal proteins A ribosomal protein (r-protein or rProtein) is any of the proteins that, in conjunction with rRNA, make up the ribosomal subunits involved in the cellular process of translation. ''E. coli'', other bacteria and Archaea have a 30S small subunit a ...

, forms the ribosomal large subunit (LSU). The 5.8S rRNA is initially transcribed along with the 18S and 28S rRNA in the 45S preribosomal RNA, along with the ITS 1 and ITS 2 (

Internal transcribed spacer Internal transcribed spacer (ITS) is the spacer DNA situated between the small-subunit ribosomal RNA (rRNA) and large-subunit rRNA genes in the chromosome or the corresponding transcribed region in the polycistronic rRNA precursor transcript. I ...

) and a 5’ and 3’ ETS ( External transcribed spacer). The 5.8S rRNA is located between the two ITS regions, with ITS1 separating it from the 18S rRNA in the 5' direction, and ITS2 separating it from the 28S rRNA in the 3' direction. The ITS and ETS are cleaved away during rRNA maturation. This is accomplished through a continuous cleavage pathway performed by both endonuclease and exonuclease enzymes, cutting the spacers at specific locations.

References

External links

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Arabidopsis 5.8S rRNA sequence

Rice 5.8S rRNA sequence
Ribosomal RNA {{molecular-cell-biology-stub