Ribosomal Proteins: Proteins found in ribosomes. They are believed to have a catalytic function in reconstituting biologically active ribosomal subunits.Ribosomal Protein S6: A ribosomal protein that may play a role in controlling cell growth and proliferation. It is a major substrate of RIBOSOMAL PROTEIN S6 KINASES and plays a role in regulating the translation (TRANSLATION, GENETIC) of RNAs that contain an RNA 5' TERMINAL OLIGOPYRIMIDINE SEQUENCE.Ribosomes: Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.Ribosomal Protein S6 Kinases: A family of protein serine/threonine kinases which act as intracellular signalling intermediates. Ribosomal protein S6 kinases are activated through phosphorylation in response to a variety of HORMONES and INTERCELLULAR SIGNALING PEPTIDES AND PROTEINS. Phosphorylation of RIBOSOMAL PROTEIN S6 by enzymes in this class results in increased expression of 5' top MRNAs. Although specific for RIBOSOMAL PROTEIN S6 members of this class of kinases can act on a number of substrates within the cell. The immunosuppressant SIROLIMUS inhibits the activation of ribosomal protein S6 kinases.RNA, Ribosomal: The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. (Dorland, 28th ed)Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Protein Biosynthesis: The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Ribosomal Protein S6 Kinases, 70-kDa: A family of ribosomal protein S6 kinases that are considered the major physiological kinases for RIBOSOMAL PROTEIN S6. Unlike RIBOSOMAL PROTEIN S6 KINASES, 90KDa the proteins in this family are sensitive to the inhibitory effects of RAPAMYCIN and contain a single kinase domain. They are referred to as 70kDa proteins, however ALTERNATIVE SPLICING of mRNAs for proteins in this class also results in 85kDa variants being formed.Anemia, Diamond-Blackfan: A rare congenital hypoplastic anemia that usually presents early in infancy. The disease is characterized by a moderate to severe macrocytic anemia, occasional neutropenia or thrombocytosis, a normocellular bone marrow with erythroid hypoplasia, and an increased risk of developing leukemia. (Curr Opin Hematol 2000 Mar;7(2):85-94)Saccharomyces cerevisiae: A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.Bacterial Proteins: Proteins found in any species of bacterium.Ribosome Subunits, Large, Eukaryotic: The large subunit of the 80s ribosome of eukaryotes. It is composed of the 28S RIBOSOMAL RNA, the 5.8S RIBOSOMAL RNA, the 5S RIBOSOMAL RNA, and about 50 different RIBOSOMAL PROTEINS.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.RNA, Bacterial: Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Polyribosomes: A multiribosomal structure representing a linear array of RIBOSOMES held together by messenger RNA; (RNA, MESSENGER); They represent the active complexes in cellular protein synthesis and are able to incorporate amino acids into polypeptides both in vivo and in vitro. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)Nucleic Acid Conformation: The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.Ribosome Subunits, Small, Eukaryotic: The small subunit of the 80s ribosome of eukaryotes. It is composed of the 18S RIBOSOMAL RNA and 32 different RIBOSOMAL PROTEINS.Geobacillus stearothermophilus: A species of GRAM-POSITIVE ENDOSPORE-FORMING BACTERIA in the family BACILLACEAE, found in soil, hot springs, Arctic waters, ocean sediments, and spoiled food products.Thermus thermophilus: A species of gram-negative, aerobic, rod-shaped bacteria found in hot springs of neutral to alkaline pH, as well as in hot-water heaters.Cell Nucleolus: Within most types of eukaryotic CELL NUCLEUS, a distinct region, not delimited by a membrane, in which some species of rRNA (RNA, RIBOSOMAL) are synthesized and assembled into ribonucleoprotein subunits of ribosomes. In the nucleolus rRNA is transcribed from a nucleolar organizer, i.e., a group of tandemly repeated chromosomal genes which encode rRNA and which are transcribed by RNA polymerase I. (Singleton & Sainsbury, Dictionary of Microbiology & Molecular Biology, 2d ed)Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.RNA, Ribosomal, 5S: Constituent of the 50S subunit of prokaryotic ribosomes containing about 120 nucleotides and 34 proteins. It is also a constituent of the 60S subunit of eukaryotic ribosomes. 5S rRNA is involved in initiation of polypeptide synthesis.Ribosomal Protein S6 Kinases, 90-kDa: A family of ribosomal protein S6 kinases that are structurally distinguished from RIBOSOMAL PROTEIN S6 KINASES, 70-KDA by their apparent molecular size and the fact they contain two functional kinase domains. Although considered RIBOSOMAL PROTEIN S6 KINASES, members of this family are activated via the MAP KINASE SIGNALING SYSTEM and have been shown to act on a diverse array of substrates that are involved in cellular regulation such as RIBOSOMAL PROTEIN S6 and CAMP RESPONSE ELEMENT-BINDING PROTEIN.Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.Genes, Fungal: The functional hereditary units of FUNGI.Sequence Homology, Nucleic Acid: The sequential correspondence of nucleotides in one nucleic acid molecule with those of another nucleic acid molecule. Sequence homology is an indication of the genetic relatedness of different organisms and gene function.Genes: A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms.RNA, Ribosomal, 23S: Constituent of 50S subunit of prokaryotic ribosomes containing about 3200 nucleotides. 23S rRNA is involved in the initiation of polypeptide synthesis.Operon: In bacteria, a group of metabolically related genes, with a common promoter, whose transcription into a single polycistronic MESSENGER RNA is under the control of an OPERATOR REGION.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Poly U: A group of uridine ribonucleotides in which the phosphate residues of each uridine ribonucleotide act as bridges in forming diester linkages between the ribose moieties.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.RNA-Binding Proteins: Proteins that bind to RNA molecules. Included here are RIBONUCLEOPROTEINS and other proteins whose function is to bind specifically to RNA.Ribosome Subunits, Large: The largest ribonucleoprotein component of RIBOSOMES. It contains the domains which catalyze formation of the peptide bond and translocation of the ribosome along the MESSENGER RNA during GENETIC TRANSLATION.Ribosome Subunits, Small, Bacterial: The small subunit of eubacterial RIBOSOMES. It is composed of the 16S RIBOSOMAL RNA and about 23 different RIBOSOMAL PROTEINS.Peptide Elongation Factors: Protein factors uniquely required during the elongation phase of protein synthesis.TOR Serine-Threonine Kinases: A serine threonine kinase that controls a wide range of growth-related cellular processes. The protein is referred to as the target of RAPAMYCIN due to the discovery that SIROLIMUS (commonly known as rapamycin) forms an inhibitory complex with TACROLIMUS BINDING PROTEIN 1A that blocks the action of its enzymatic activity.Sequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.Protein Kinases: A family of enzymes that catalyze the conversion of ATP and a protein to ADP and a phosphoprotein.Saccharomyces cerevisiae Proteins: Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.Genes, Bacterial: The functional hereditary units of BACTERIA.Escherichia coli Proteins: Proteins obtained from ESCHERICHIA COLI.Chloroplasts: Plant cell inclusion bodies that contain the photosynthetic pigment CHLOROPHYLL, which is associated with the membrane of THYLAKOIDS. Chloroplasts occur in cells of leaves and young stems of plants. They are also found in some forms of PHYTOPLANKTON such as HAPTOPHYTA; DINOFLAGELLATES; DIATOMS; and CRYPTOPHYTA.RNA, Fungal: Ribonucleic acid in fungi having regulatory and catalytic roles as well as involvement in protein synthesis.Halobacterium: A genus of HALOBACTERIACEAE whose growth requires a high concentration of salt. Binary fission is by constriction.Emetine: The principal alkaloid of ipecac, from the ground roots of Uragoga (or Cephaelis) ipecacuanha or U. acuminata, of the Rubiaceae. It is used as an amebicide in many different preparations and may cause serious cardiac, hepatic, or renal damage and violent diarrhea and vomiting. Emetine inhibits protein synthesis in EUKARYOTIC CELLS but not PROKARYOTIC CELLS.RNA, Ribosomal, 18S: Constituent of the 40S subunit of eukaryotic ribosomes. 18S rRNA is involved in the initiation of polypeptide synthesis in eukaryotes.Thiostrepton: One of the CYCLIC PEPTIDES from Streptomyces that is active against gram-positive bacteria. In veterinary medicine, it has been used in mastitis caused by gram-negative organisms and in dermatologic disorders.Ribosome Subunits, Small: The small ribonucleoprotein component of RIBOSOMES. It contains the MESSENGER RNA binding site and two TRANSFER RNA binding sites - one for the incoming AMINO ACYL TRNA (A site) and the other (P site) for the peptidyl tRNA carrying the elongating peptide chain.Fungal Proteins: Proteins found in any species of fungus.Molecular Weight: The sum of the weight of all the atoms in a molecule.Codon: A set of three nucleotides in a protein coding sequence that specifies individual amino acids or a termination signal (CODON, TERMINATOR). Most codons are universal, but some organisms do not produce the transfer RNAs (RNA, TRANSFER) complementary to all codons. These codons are referred to as unassigned codons (CODONS, NONSENSE).Gene Expression Regulation, Fungal: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in fungi.RNA, Transfer: The small RNA molecules, 73-80 nucleotides long, that function during translation (TRANSLATION, GENETIC) to align AMINO ACIDS at the RIBOSOMES in a sequence determined by the mRNA (RNA, MESSENGER). There are about 30 different transfer RNAs. Each recognizes a specific CODON set on the mRNA through its own ANTICODON and as aminoacyl tRNAs (RNA, TRANSFER, AMINO ACYL), each carries a specific amino acid to the ribosome to add to the elongating peptide chains.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Electrophoresis, Gel, Two-Dimensional: Electrophoresis in which a second perpendicular electrophoretic transport is performed on the separate components resulting from the first electrophoresis. This technique is usually performed on polyacrylamide gels.Ribonucleoproteins: Complexes of RNA-binding proteins with ribonucleic acids (RNA).Plasmids: Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.Streptomycin: An antibiotic produced by the soil actinomycete Streptomyces griseus. It acts by inhibiting the initiation and elongation processes during protein synthesis.Amino Acids: Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.Restriction Mapping: Use of restriction endonucleases to analyze and generate a physical map of genomes, genes, or other segments of DNA.Peptide Chain Initiation, Translational: A process of GENETIC TRANSLATION whereby the formation of a peptide chain is started. It includes assembly of the RIBOSOME components, the MESSENGER RNA coding for the polypeptide to be made, INITIATOR TRNA, and PEPTIDE INITIATION FACTORS; and placement of the first amino acid in the peptide chain. The details and components of this process are unique for prokaryotic protein biosynthesis and eukaryotic protein biosynthesis.Sirolimus: A macrolide compound obtained from Streptomyces hygroscopicus that acts by selectively blocking the transcriptional activation of cytokines thereby inhibiting cytokine production. It is bioactive only when bound to IMMUNOPHILINS. Sirolimus is a potent immunosuppressant and possesses both antifungal and antineoplastic properties.RNA Precursors: RNA transcripts of the DNA that are in some unfinished stage of post-transcriptional processing (RNA PROCESSING, POST-TRANSCRIPTIONAL) required for function. RNA precursors may undergo several steps of RNA SPLICING during which the phosphodiester bonds at exon-intron boundaries are cleaved and the introns are excised. Consequently a new bond is formed between the ends of the exons. Resulting mature RNAs can then be used; for example, mature mRNA (RNA, MESSENGER) is used as a template for protein production.Kinetics: The rate dynamics in chemical or physical systems.Introns: Sequences of DNA in the genes that are located between the EXONS. They are transcribed along with the exons but are removed from the primary gene transcript by RNA SPLICING to leave mature RNA. Some introns code for separate genes.Paromomycin: An oligosaccharide antibiotic produced by various STREPTOMYCES.Species Specificity: The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.Blotting, Northern: Detection of RNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.RNA Processing, Post-Transcriptional: Post-transcriptional biological modification of messenger, transfer, or ribosomal RNAs or their precursors. It includes cleavage, methylation, thiolation, isopentenylation, pseudouridine formation, conformational changes, and association with ribosomal protein.Ribosome Subunits: The two dissimilar sized ribonucleoprotein complexes that comprise a RIBOSOME - the large ribosomal subunit and the small ribosomal subunit. The eukaryotic 80S ribosome is composed of a 60S large subunit and a 40S small subunit. The bacterial 70S ribosome is composed of a 50S large subunit and a 30S small subunit.Conserved Sequence: A sequence of amino acids in a polypeptide or of nucleotides in DNA or RNA that is similar across multiple species. A known set of conserved sequences is represented by a CONSENSUS SEQUENCE. AMINO ACID MOTIFS are often composed of conserved sequences.Gene Expression Regulation: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.RNA, Ribosomal, 16S: Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.Peptide Chain Elongation, Translational: A process of GENETIC TRANSLATION, when an amino acid is transferred from its cognate TRANSFER RNA to the lengthening chain of PEPTIDES.PhosphoproteinsHaloarcula marismortui: A species of halophilic archaea distinguished by its production of acid from sugar. This species was previously called Halobacterium marismortui.Ribosome Subunits, Large, Bacterial: The large subunit of the eubacterial 70s ribosome. It is composed of the 23S RIBOSOMAL RNA, the 5S RIBOSOMAL RNA, and about 37 different RIBOSOMAL PROTEINS.Imidoesters: Esters of the hypothetical imidic acids. They react with amines or amino acids to form amidines and are therefore used to modify protein structures and as cross-linking agents.Peptide Initiation Factors: Protein factors uniquely required during the initiation phase of protein synthesis in GENETIC TRANSLATION.DNA, Fungal: Deoxyribonucleic acid that makes up the genetic material of fungi.Trichodermin: Antifungal metabolite from several fungi, mainly Trichoderma viride; inhibits protein synthesis by binding to ribosomes; proposed as antifungal and antineoplastic; used as tool in cellular biochemistry.RNA: A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. (Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)Peptide Elongation Factor G: Peptide Elongation Factor G catalyzes the translocation of peptidyl-tRNA from the A to the P site of bacterial ribosomes by a process linked to hydrolysis of GTP to GDP.Plants: Multicellular, eukaryotic life forms of kingdom Plantae (sensu lato), comprising the VIRIDIPLANTAE; RHODOPHYTA; and GLAUCOPHYTA; all of which acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations.RNA, Ribosomal, 28S: Constituent of the 60S subunit of eukaryotic ribosomes. 28S rRNA is involved in the initiation of polypeptide synthesis in eukaryotes.Cell Nucleus: Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)DNA: A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).Promoter Regions, Genetic: DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Peptide Elongation Factor 2: Peptide Elongation Factor 2 catalyzes the translocation of peptidyl-tRNA from the A site to the P site of eukaryotic ribosomes by a process linked to the hydrolysis of GTP to GDP.Centrifugation, Density Gradient: Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Multigene Family: A set of genes descended by duplication and variation from some ancestral gene. Such genes may be clustered together on the same chromosome or dispersed on different chromosomes. Examples of multigene families include those that encode the hemoglobins, immunoglobulins, histocompatibility antigens, actins, tubulins, keratins, collagens, heat shock proteins, salivary glue proteins, chorion proteins, cuticle proteins, yolk proteins, and phaseolins, as well as histones, ribosomal RNA, and transfer RNA genes. The latter three are examples of reiterated genes, where hundreds of identical genes are present in a tandem array. (King & Stanfield, A Dictionary of Genetics, 4th ed)Eukaryotic Initiation Factor-4E: A peptide initiation factor that binds specifically to the 5' MRNA CAP STRUCTURE of MRNA in the CYTOPLASM. It is a component of the trimeric complex EIF4F.Archaeal Proteins: Proteins found in any species of archaeon.Chromosome Mapping: Any method used for determining the location of and relative distances between genes on a chromosome.