thebacterialflagellum
... the late 17th century [1]. He manufactured microscopes and discovered small animals in his well water. He described them as “little eels, or worms, lying all huddled up together and wriggling” [2]. The bacteria he was observing was spirillum, probably Spirillum Volutans. However, Leeuwenhoek did not ...
... the late 17th century [1]. He manufactured microscopes and discovered small animals in his well water. He described them as “little eels, or worms, lying all huddled up together and wriggling” [2]. The bacteria he was observing was spirillum, probably Spirillum Volutans. However, Leeuwenhoek did not ...
The Cell Membrane
... instructions within chromosomes. The instructions tell how to synthesize the proteins that determine cell structure and function. Chromosomes also contain various proteins that control expression of the genetic information. ...
... instructions within chromosomes. The instructions tell how to synthesize the proteins that determine cell structure and function. Chromosomes also contain various proteins that control expression of the genetic information. ...
1 Nucleoli: Composition, Function and Dynamics
... localization of pre-miRNAs and Dicer-like 1 (DCL1) to D-bodies also suggests a role for the nucleolus in the maturation of miRNAs (Pontes and Pikaard, 2008). Some precursor and mature miRNAs are enriched in the nucleolus of mammalian cells possibly for modification, assembly or to regulate snoRNA ac ...
... localization of pre-miRNAs and Dicer-like 1 (DCL1) to D-bodies also suggests a role for the nucleolus in the maturation of miRNAs (Pontes and Pikaard, 2008). Some precursor and mature miRNAs are enriched in the nucleolus of mammalian cells possibly for modification, assembly or to regulate snoRNA ac ...
Nucleoli: Composition, Function, and Dynamics
... Department of Cell and Developmental Biology, John Innes Center, Norwich NR4 7UH, United Kingdom (P.S.); and Division of Plant Sciences and Cell and Molecular Sciences, University of Dundee at the James Hutton Institute, Dundee DD2 5DA, United Kingdom (J.B.) RDNA AND NUCLEOLAR CHROMATIN rDNA Structu ...
... Department of Cell and Developmental Biology, John Innes Center, Norwich NR4 7UH, United Kingdom (P.S.); and Division of Plant Sciences and Cell and Molecular Sciences, University of Dundee at the James Hutton Institute, Dundee DD2 5DA, United Kingdom (J.B.) RDNA AND NUCLEOLAR CHROMATIN rDNA Structu ...
Small Nucleolar RNAs and Pre
... The functions of U3, U14, and MRP, which are among the more abundant snoRNAs, have been examined in detail in yeast and vertebrates (Maxwell and Fournier, 1995; Smith and Steitz, 1997; Tollervey and Kiss, 1997). U3 and U14, as well as U17, E3, and possibly U22, are needed for the initial 59 ETS clea ...
... The functions of U3, U14, and MRP, which are among the more abundant snoRNAs, have been examined in detail in yeast and vertebrates (Maxwell and Fournier, 1995; Smith and Steitz, 1997; Tollervey and Kiss, 1997). U3 and U14, as well as U17, E3, and possibly U22, are needed for the initial 59 ETS clea ...
How Optimized Is the Translational Machinery in
... be the same as that in the baseline condition when Q j exactly matches p j , e.g., when Q 1 5 p 1 in Figure 1. The baseline condition therefore seems to guarantee a relatively small Y value over a wide fluctuation of Q j values. Y will be smaller than the baseline condition only when Q j values are ...
... be the same as that in the baseline condition when Q j exactly matches p j , e.g., when Q 1 5 p 1 in Figure 1. The baseline condition therefore seems to guarantee a relatively small Y value over a wide fluctuation of Q j values. Y will be smaller than the baseline condition only when Q j values are ...
Cutting the nonsense: the degradation of PTC containing mRNAs
... and at least one of the three different classes of regulatory B subunit which are known to be encoded by at least 13 genes and various splice variants. It is evident that an important function of these regulatory subunits is to target the PP2A holoenzyme to separate cellular locations and complexes ...
... and at least one of the three different classes of regulatory B subunit which are known to be encoded by at least 13 genes and various splice variants. It is evident that an important function of these regulatory subunits is to target the PP2A holoenzyme to separate cellular locations and complexes ...
RNA-binding proteins
... polyadenylation, mRNA stability, mRNA localization and translation (Curtis et al., 1995; Wickens et al., 2000; de Moor and Richter, 2001; Johnstone and Lasko, 2001). In the C. elegans genome, approximately 500 genes are annotated to encode RBPs (Wormbase), as they have one or more known RNA binding ...
... polyadenylation, mRNA stability, mRNA localization and translation (Curtis et al., 1995; Wickens et al., 2000; de Moor and Richter, 2001; Johnstone and Lasko, 2001). In the C. elegans genome, approximately 500 genes are annotated to encode RBPs (Wormbase), as they have one or more known RNA binding ...
Inhibition of c-myc Expression in Cells by Targeting an RNA
... RNA-binding proteins can influence mRNA transport, localization, translation, and degradation (McCarthy and Kollmus, 1995). Several proteins have been identified that interact with regions of the c-myc mRNA and regulate its metabolism (Bernstein et al., 1992; Zhang et al., 1993; Prokipcak et al., 19 ...
... RNA-binding proteins can influence mRNA transport, localization, translation, and degradation (McCarthy and Kollmus, 1995). Several proteins have been identified that interact with regions of the c-myc mRNA and regulate its metabolism (Bernstein et al., 1992; Zhang et al., 1993; Prokipcak et al., 19 ...
Endosomal transport of septin mRNA and protein indicates local
... Second, the authors suggest that translation occurs on the shuttling endosomes, yet the experiments needed to actually prove this have not been performed (see specific comments 9 & 10 below). Although co-translational delivery of some portion of Cdc3 protein via endosomes cannot be ruled out, it is ...
... Second, the authors suggest that translation occurs on the shuttling endosomes, yet the experiments needed to actually prove this have not been performed (see specific comments 9 & 10 below). Although co-translational delivery of some portion of Cdc3 protein via endosomes cannot be ruled out, it is ...
G PROTEIN βγ SUBUNITS
... could itself regulate effectors came to light when Logothetis et al (2) showed that Gβγ activated a K+ -selective ion channel (IKACh ) in cardiac atrial cells. The following year, Whiteway et al (3) showed that Gβγ , not Gα , carried the signal from the yeast mating receptor to the response pathway. ...
... could itself regulate effectors came to light when Logothetis et al (2) showed that Gβγ activated a K+ -selective ion channel (IKACh ) in cardiac atrial cells. The following year, Whiteway et al (3) showed that Gβγ , not Gα , carried the signal from the yeast mating receptor to the response pathway. ...
Origins and Early Evolution of the tRNA Molecule
... do the job of a protein [1]. tRNA, discovered by Paul Zamecnik and collaborators [2], is a literal “adaptor” molecule [3] that mediates the translation of information from messenger RNAs (mRNAs). tRNA was the first non-coding RNA to be discovered. Now, our knowledge of the functions of non-coding RN ...
... do the job of a protein [1]. tRNA, discovered by Paul Zamecnik and collaborators [2], is a literal “adaptor” molecule [3] that mediates the translation of information from messenger RNAs (mRNAs). tRNA was the first non-coding RNA to be discovered. Now, our knowledge of the functions of non-coding RN ...
Full-Text PDF
... bacteria and other micro-organisms. Recently, the concept of antibiotics has been enlarged to include anti-fungals and other compounds [1]. Antibiotics can be classified according to how they affect the cellular component or system, and to how they work, namely by killing the cell (bactericidal drug ...
... bacteria and other micro-organisms. Recently, the concept of antibiotics has been enlarged to include anti-fungals and other compounds [1]. Antibiotics can be classified according to how they affect the cellular component or system, and to how they work, namely by killing the cell (bactericidal drug ...
The Proteomic Code: a molecular recognition code for proteins
... have supported cellular or pre-cellular life. Some theories about the origin of life present RNA-based catalysis and information storage as the first step in the evolution of cellular life. ...
... have supported cellular or pre-cellular life. Some theories about the origin of life present RNA-based catalysis and information storage as the first step in the evolution of cellular life. ...
RNAi (PDF) (1.14 MB)
... RNA interference (RNAi) has emerged as one of the most promising tools for biological research. It is thought that RNAi may have evolved originally as a defense mechanism against foreign parasitic nucleic acid sequences and functions by specifically knocking down the activity of target genes. RNAi ha ...
... RNA interference (RNAi) has emerged as one of the most promising tools for biological research. It is thought that RNAi may have evolved originally as a defense mechanism against foreign parasitic nucleic acid sequences and functions by specifically knocking down the activity of target genes. RNAi ha ...
Distribution and phylogeny of the bacterial translational GTPases
... Protein synthesis is vital for all living cells, being the last phase of expression of information stored in protein-coding genes. It is performed by the ribosome, a highly conserved RNA-protein complex. The prokaryotic ribosome consists of two asymmetric subunits: 30S and 50S. The small (30S) subun ...
... Protein synthesis is vital for all living cells, being the last phase of expression of information stored in protein-coding genes. It is performed by the ribosome, a highly conserved RNA-protein complex. The prokaryotic ribosome consists of two asymmetric subunits: 30S and 50S. The small (30S) subun ...
μMACS™ mRNA Isolation Kits
... and washing steps. The μMACS mRNA Isolation is a robust and reproducible procedure based on MACS® Technology. It enables direct isolation of mRNA without prior preparation of total RNA. With the μMACS mRNA Isolation Kits full length, intact mRNA can be obtained from fresh, frozen, or cultured cells1 ...
... and washing steps. The μMACS mRNA Isolation is a robust and reproducible procedure based on MACS® Technology. It enables direct isolation of mRNA without prior preparation of total RNA. With the μMACS mRNA Isolation Kits full length, intact mRNA can be obtained from fresh, frozen, or cultured cells1 ...
Single Cell Analysis of RNA-mediated Histone H3.3 Transcription Site
... senescing cells (13, 14). HIRA and the SNF2-like chromatinremodeling factor, chromodomain helicase DNA-binding protein 1 (CHD1), are both required for H3.3 incorporation into the Drosophila male pronucleus (15–17). Additionally, CHD2 regulates H3.3 assembly at MyoD and myogenic regulatory sequences ...
... senescing cells (13, 14). HIRA and the SNF2-like chromatinremodeling factor, chromodomain helicase DNA-binding protein 1 (CHD1), are both required for H3.3 incorporation into the Drosophila male pronucleus (15–17). Additionally, CHD2 regulates H3.3 assembly at MyoD and myogenic regulatory sequences ...
Two genetic codes: Repetitive syntax for active non
... the living world. In contrast to non-coding RNAs that are built of repetitive nucleotide syntax, the sequences that serve as templates for proteins share—as main characteristics—a non-repetitive syntax. Whereas non-coding RNAs build groups that serve as regulatory tools in nearly all genetic process ...
... the living world. In contrast to non-coding RNAs that are built of repetitive nucleotide syntax, the sequences that serve as templates for proteins share—as main characteristics—a non-repetitive syntax. Whereas non-coding RNAs build groups that serve as regulatory tools in nearly all genetic process ...
A Role for A-to-I RNA Editing in Temperature Adaptation
... as guanosine by the ribosome (2), editing can result in amino acid recoding. This process is probably ubiquitous in true metazoans, since they all express ADAR homologs (28). By rewriting genetic information, organisms create novel protein isoforms that, in many cases, have modified functions. Furth ...
... as guanosine by the ribosome (2), editing can result in amino acid recoding. This process is probably ubiquitous in true metazoans, since they all express ADAR homologs (28). By rewriting genetic information, organisms create novel protein isoforms that, in many cases, have modified functions. Furth ...
Invariant amino acids essential for decoding function of polypeptide
... and third nucleotides of the stop codons are decoded directly by a linear ‘protein anticodons’ (PAT in RF1 and SPF in RF2) (6–8). For eukaryotes, it is now established that the specificity of stop codon recognition is associated with the eRF1 rather than the ribosome (9) and the recognition site is ...
... and third nucleotides of the stop codons are decoded directly by a linear ‘protein anticodons’ (PAT in RF1 and SPF in RF2) (6–8). For eukaryotes, it is now established that the specificity of stop codon recognition is associated with the eRF1 rather than the ribosome (9) and the recognition site is ...
RNAi: nature abhors a double-strand György Hutvágner and Phillip
... Dicer makes both siRNAs and stRNAs, so why are stRNAs (and all but one of the newly identified miRNAs) singlestranded, whereas siRNAs are double-stranded? One possibility is that the structure of the precursor, with its single-stranded loop and bulges and mismatches in the stem, guides Dicer to cut ...
... Dicer makes both siRNAs and stRNAs, so why are stRNAs (and all but one of the newly identified miRNAs) singlestranded, whereas siRNAs are double-stranded? One possibility is that the structure of the precursor, with its single-stranded loop and bulges and mismatches in the stem, guides Dicer to cut ...
Non-coding RNAs - Biology Department | UNC Chapel Hill
... Figure 1 | Anatomical features of Sm- and Lsm-class small nuclear RNAs. a | Sm-class small nuclear (sn)RNAs are transcribed by RNA polymerase II and contain three important recognition elements (boxed): a 5′-trimethylguanosine (TMG) cap, an Sm-protein-binding site (Sm site) and a 3′ stem–loop struct ...
... Figure 1 | Anatomical features of Sm- and Lsm-class small nuclear RNAs. a | Sm-class small nuclear (sn)RNAs are transcribed by RNA polymerase II and contain three important recognition elements (boxed): a 5′-trimethylguanosine (TMG) cap, an Sm-protein-binding site (Sm site) and a 3′ stem–loop struct ...
Diversity of heterotrimeric G-protein γ subunits in plants | SpringerLink
... selectivity to G-proteins. Three unconventional Gγ subunits were recently reported in Arabidopsis, rice and soybean but no structural analysis has been reported so far. Their relationship with conventional Gγ subunits and taxonomical distribution has not been yet demonstrated. Results: After an exte ...
... selectivity to G-proteins. Three unconventional Gγ subunits were recently reported in Arabidopsis, rice and soybean but no structural analysis has been reported so far. Their relationship with conventional Gγ subunits and taxonomical distribution has not been yet demonstrated. Results: After an exte ...
Antibiotic use and abuse: A threat to mitochondria and chloroplasts
... industrial synthesis [33]. Since the introduction of antibiotics for the treatment and prevention of bacterial infection about 7 decades ago, a wide variety of antibiotics have been used in human medicine as well as in agriculture for preventing or treating animal and plant bacterial infections [34] ...
... industrial synthesis [33]. Since the introduction of antibiotics for the treatment and prevention of bacterial infection about 7 decades ago, a wide variety of antibiotics have been used in human medicine as well as in agriculture for preventing or treating animal and plant bacterial infections [34] ...
Ribosome
The ribosome (/ˈraɪbɵˌzoʊm/) is a large and complex molecular machine, found within all living cells, that serves as the site of biological protein synthesis (translation). Ribosomes link amino acids together in the order specified by messenger RNA (mRNA) molecules. Ribosomes consist of two major components: the small ribosomal subunit, which reads the RNA, and the large subunit, which joins amino acids to form a polypeptide chain. Each subunit is composed of one or more ribosomal RNA (rRNA) molecules and a variety of proteins. The ribosomes and associated molecules are also known as the translational apparatus.The sequence of DNA encoding for a protein may be copied many times into RNA chains of a similar sequence. Ribosomes can bind to an RNA chain and use it as a template for determining the correct sequence of amino acids in a particular protein. Amino acids are selected, collected and carried to the ribosome by transfer RNA (tRNA molecules), which enter one part of the ribosome and bind to the messenger RNA chain. The attached amino acids are then linked together by another part of the ribosome. Once the protein is produced, it can then fold to produce a specific functional three-dimensional structure.A ribosome is made from complexes of RNAs and proteins and is therefore a ribonucleoprotein. Each ribosome is divided into two subunits: 1. a smaller subunit which binds to a larger subunit and the mRNA pattern, and 2. a larger subunit which binds to the tRNA, the amino acids, and the smaller subunit. When a ribosome finishes reading an mRNA molecule, these two subunits split apart. Ribosomes are ribozymes, because the catalytic peptidyl transferase activity that links amino acids together is performed by the ribosomal RNA. Ribosomes are often embedded in the intercellular membranes that make up the rough endoplasmic reticulum.Ribosomes from bacteria, archaea and eukaryotes (the three domains of life on Earth) differ in their size, sequence, structure, and the ratio of protein to RNA. The differences in structure allow some antibiotics to kill bacteria by inhibiting their ribosomes, while leaving human ribosomes unaffected. In bacteria and archaea, more than one ribosome may move along a single mRNA chain at one time, each ""reading"" its sequence and producing a corresponding protein molecule. The ribosomes in the mitochondria of eukaryotic cells functionally resemble many features of those in bacteria, reflecting the likely evolutionary origin of mitochondria.