>PF00573 Ribosomal_L4: Ribosomal protein L4/L1 family; InterPro: IPR002136 Ribosomes are the particles that catalyse mRNA-directed protein synthesis in all organisms
The codons of the mRNA are exposed on the ribosome to allow tRNA binding. This leads to the incorporation of amino acids into the growing polypeptide chain in accordance with the genetic information. Incoming amino acid monomers enter the ribosomal A site in the form of aminoacyl-tRNAs complexed with elongation factor Tu (EF-Tu) and GTP. The growing polypeptide chain, situated in the P site as peptidyl-tRNA, is then transferred to aminoacyl-tRNA and the new peptidyl-tRNA, extended by one residue, is translocated to the P site with the aid the elongation factor G (EF-G) and GTP as the deacylated tRNA is released from the ribosome through one or more exit sites [, ]. About 2/3 of the mass of the ribosome consists of RNA and 1/3 of protein. The proteins are named in accordance with the subunit of the ribosome which they belong to - the small (S1 to S31) and the large (L1 to L44). Usually they decorate the rRNA cores of the subunits. Many ribosomal proteins, particularly those of the large subunit, are composed of a globular, surfaced-exposed domain with long finger-like projections that extend into the rRNA core to stabilise its structure. Most of the proteins interact with multiple RNA elements, often from different domains. In the large subunit, about 1/3 of the 23S rRNA nucleotides are at least in van der Waal's contact with protein, and L22 interacts with all six domains of the 23S rRNA. Proteins S4 and S7, which initiate assembly of the 16S rRNA, are located at junctions of five and four RNA helices, respectively. In this way proteins serve to organise and stabilise the rRNA tertiary structure. While the crucial activities of decoding and peptide transfer are RNA based, proteins play an active role in functions that may have evolved to streamline the process of protein synthesis. In addition to their function in the ribosome, many ribosomal proteins have some function 'outside' the ribosome [, ]. This family includes ribosomal L4/L1 from eukaryotes and plants and L4 from bacteria. L4 from yeast has been shown to bind rRNA []. These proteins have 246 (plant) to 427 (human) amino acids.; GO: 0003735 structural constituent of ribosome, 0006412 translation, 0005840 ribosome; PDB: 3IZR_D 1VSA_D 3D5D_F 3MS1_E 3F1F_F 3PYO_E 3MRZ_E 3F1H_F 3PYR_E 1VSP_D ....
>PRK05319 rplD 50S ribosomal protein L4; Provisional
One of the primary rRNA binding proteins, this protein initially binds near the 5'-end of the 23S rRNA. It is important during the early stages of 50S assembly. It makes multiple contacts with different domains of the 23S rRNA in the assembled 50S subunit and ribosome.
>PRK04042 rpl4lp 50S ribosomal protein L4P; Provisional
RPL4, ribosomal protein L3; eukaryotic ribosome, r
98.74
>2ftc_D Mitochondrial ribosomal protein L4 isoform A, mitochondrial 39S ribosomal protein L3; mitochondrial ribosome, large ribosomal subunit, ribosomal R ribosome; 12.10A {Bos taurus} PDB: 3iy9_D