40S ribosomal protein S25 (eS25) is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...

that in humans is encoded by the ''RPS25''

gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...

. Ribosomes are cellular macromolecules that

catalyze Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...

protein synthesis Protein biosynthesis (or protein synthesis) is a core biological process, occurring inside cells, balancing the loss of cellular proteins (via degradation or export) through the production of new proteins. Proteins perform a number of critical ...

across all kingdoms of life. The eukaryotic ribosome consists of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 distinct proteins. The RPS25 gene encodes the eukaryote-specific

ribosomal protein 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 an ...

eS25 that is a component of the 40S subunit. As is typical for genes encoding ribosomal proteins, there are multiple processed

pseudogenes Pseudogenes are nonfunctional segments of DNA that resemble functional genes. Most arise as superfluous copies of functional genes, either directly by DNA duplication or indirectly by reverse transcription of an mRNA transcript. Pseudogenes are ...

of this gene dispersed through the genome.

Interactions

Besides the interactions that position eS25 at its location in the E site region of the 40S ribosomal subunit, eS25 has been suggested to interact with other cellular proteins. One study has found that eS25 interacts with MDM2 as part of a regulatory feedback loop that stabilizes

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 ...

. Additionally, eS25 has been shown to interact with

CDC5L Cell division cycle 5-like protein is a protein that in humans is encoded by the ''CDC5L'' gene. Function The protein encoded by this gene shares a significant similarity with ''Schizosaccharomyces pombe'' cdc5 gene product, which is a cell c ...

Function

As a ribosomal protein, eS25 likely plays a role in general protein synthesis; however, the RPS25 gene is non-essential for cellular viability in budding yeast and in select mammalian cell lines, implying that it is not essential for eukaryotic protein synthesis. Studies have implicated eS25 in the control of several specialized forms of translation, including that mediated by viral IRESs.

Interactions

Function

See also

References

Further reading