Ribosomes structure and function

Kurland, C. G. Aspects of ribosome structure and function, in Molecular Mechanisms of Protein Biosynthesis (eds.) Weissbach, H., Pestka, S., p. 81, New York, Academic Press 1977... 

Ribosomal RNA is present in the ribosomes, which contain approximately an equal mass of protein. Ribosomal RNA makes up about 80 percent of the total RNA in the cell and is of several types, distinguished from one another by their sedimentation rates in an ultracentrifuge (Chap. 4). Bacterial ribosomes, for example, contain three types of RNA 5S, 16S, and 23S. The details of ribosome structure and function are treated in Chap. 17. 

Chapters 11 through 14 deal with aspects of molecular biology in archaea and include, respectively, DNA structure and replication by P. Forterre transcription apparatus by W. Zillig et al. translation apparatus by R. Amils et al. and ribosomal structure and function by A. Matheson et al. 

Electron microscopy can give information about ribosomal structure and function, but X-ray crystallography has given far more detailed information. 

Plesner, P. 1961. Changes in ribosome structure and function during synchronized cell division. Cold Spring Harbor Symp. Quant. Biol., 26 159-162. 

Kurland, C.G. Ribosome structure and function emergent. Science 169, 1171-1177(1970)... 

Finally, to produce the structural and functional devices of the cell, polypeptides are synthesized by ribosomal translation of the mRNA. The supramolecular complex of the E. coli ribosome consists of 52 protein and three RNA molecules. The power of programmed molecular recognition is impressively demonstrated by the fact that aU of the individual 55 ribosomal building blocks spontaneously assemble to form the functional supramolecular complex by means of noncovalent interactions. The ribosome contains two subunits, the 308 subunit, with a molecular weight of about 930 kDa, and the 1590-kDa 50S subunit, forming particles of about 25-nm diameter. The resolution of the well-defined three-dimensional structure of the ribosome and the exact topographical constitution of its components are still under active investigation. Nevertheless, the localization of the multiple enzymatic domains, e.g., the peptidyl transferase, are well known, and thus the fundamental functions of the entire supramolecular machine is understood [24]. 

Ginisty H, Serin G, Ghisolfi-Nieto L, Roger B, Libante V, Amalric F, Bouvet P (2000) Interaction of Nucleolin with an Evolutionarily Conserved Pre-ribosomal RNA Sequence Is Required for the Assembly of the Primary Processing Complex. J Biol Chem 275 18845-18850 Ginisty H, Sicard H, Roger B, Bouvet P (1999) Structure and functions of nucleolin. J Cell Sci 112 761-772... 

Cellular RNAs vary widely in their size, structure, and lifespan. The great majority of them are ribosomal RNA (rRNA), which in several forms is a structural and functional component of ribosomes (see p.250). Ribosomal RNA is produced from DNA by transcription in the nucleolus, and it is processed there and assembled with proteins to form ribosome subunits (see pp.208, 242). The bacterial 16S-rRNA shown in Fig. A, with 1542 nucleotides (nt), is a component of the small ribosomae subunit, while the much smaller 5S-rRNA (118 nt) is located in the large subunit. 

Doudna JA, Rath VL (2002) Structure and function of the eukaryotic ribosome the next frontier. Cell 109 153-156... 

Ribosomal proteins Ribosomal proteins are present in considerably greater numbers in eukaryotic ribosomes than in prokaryotic ribosomes. These proteins play a number of roles in the structure and function of the ribosome and its interactions with other components of the translation system. 

RNA has a variety of functions within a cell for each function, a specific type of RNA is required. Messenger RNA (mRNA) serves as intermediaries for carrying genetic messages from the DNA to the ribosomes where protein synthesis lakes place. Ribosomal RNA (rRNA) serves both structural and functional roles in the ribosome it is diverse, both in terms of its size and structure. Transfer RNAs (tRNAs) are small molecules that have a central role in protein synthesis. Other RNA molecules, called ribozymes, function as enzymes to catalyze chemical transformations. Although ribozymes most often catalyze cleavage of the... 

The ribosome structure is perhaps the most impressive natural rotaxane. Messenger RNA, as the rotaxane thread, is clamped by the ribosomal protein subunits which read each codon and transcribe it into a sequence of amino acids that are introduced by transfer RNAs to build up the desired protein. The importance of the ribosomes has been reflected in the number of Nobel Prize recipients associated with their discovery (Palade in 1974) and elucidation of their structures and functions (Ramakrishnan, Steitz and Yonath in 2009). 

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