RPL5 : ribosomal protein L5
Description
The RPL5 (ribosomal protein L5) is a protein-coding gene located on chromosome 1.
The RPL5 gene provides instructions for making one of approximately 80 different ribosomal proteins, which are components of cellular structures called ribosomes. Ribosomes process the cell's genetic instructions to create proteins. Each ribosome is made up of two parts (subunits) called the large and small subunits. The protein produced from the RPL5 gene is among those found in the large subunit. The specific functions of the RPL5 protein and the other ribosomal proteins within these subunits are unclear. Some ribosomal proteins are involved in the assembly or stability of ribosomes. Others help carry out the ribosome's main function of building new proteins. Studies suggest that some ribosomal proteins may have other functions, such as participating in chemical signaling pathways within the cell, regulating cell division, and controlling the self-destruction of cells (apoptosis). Research suggests that the protein produced from the RPL5 gene also normally has tumor suppressor function, which means that it helps keep cells from growing and dividing too rapidly or in an uncontrolled way.
RPL5 is a component of the ribosome, a large ribonucleoprotein complex responsible for protein synthesis in the cell. The ribosome consists of two subunits: the small subunit (SSU) and the large subunit (LSU). The SSU binds messenger RNAs (mRNAs) and translates the encoded message by selecting cognate aminoacyl-transfer RNA (tRNA) molecules. The LSU contains the ribosomal catalytic site termed the peptidyl transferase center (PTC), which catalyzes the formation of peptide bonds, thereby polymerizing the amino acids delivered by tRNAs into a polypeptide chain. The nascent polypeptides leave the ribosome through a tunnel in the LSU and interact with protein factors that function in enzymatic processing, targeting, and the membrane insertion of nascent chains at the exit of the ribosomal tunnel. RPL5, as part of the 5S RNP/5S ribonucleoprotein particle, is an essential component of the LSU, required for its formation and the maturation of rRNAs. It also couples ribosome biogenesis to p53/TP53 activation. As part of the 5S RNP it accumulates in the nucleoplasm and inhibits MDM2, when ribosome biogenesis is perturbed, mediating the stabilization and the activation of TP53.
RPL5 is also known as L5, MSTP030, PPP1R135, uL18.
