Kooperativer Bibliotheksverbund

Berlin Brandenburg

and
and

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Year
  • 1
    Language: English
    In: Proceedings of the National Academy of Sciences of the United States of America, 23 November 2010, Vol.107(47), pp.20435-40
    Description: The abundant class of bacterial Hfq-associated small regulatory RNAs (sRNAs) parallels animal microRNAs in their ability to control multiple genes at the posttranscriptional level by short and imperfect base pairing. In contrast to the universal length and seed pairing mechanism of microRNAs, the sRNAs are heterogeneous in size and structure, and how they regulate multiple targets is not well understood. This paper provides evidence that a 5' located sRNA domain is a critical element for the control of a large posttranscriptional regulon. We show that the conserved 5' end of RybB sRNA recognizes multiple mRNAs of Salmonella outer membrane proteins by ≥7-bp Watson-Crick pairing. When fused to an unrelated sRNA, the 5' domain is sufficient to guide target mRNA degradation and maintain σ(E)-dependent envelope homeostasis. RybB sites in mRNAs are often conserved and flanked by 3' adenosine. They are found in a wide sequence window ranging from the upstream untranslated region to the deep coding sequence, indicating that some targets might be repressed at the level of translation, whereas others are repressed primarily by mRNA destabilization. Autonomous 5' domains seem more common in sRNAs than appreciated and might improve the design of synthetic RNA regulators.
    Keywords: Bacterial Outer Membrane Proteins -- Metabolism ; Gene Expression Regulation, Bacterial -- Genetics ; RNA, Messenger -- Metabolism ; Regulatory Sequences, Ribonucleic Acid -- Genetics ; Regulon -- Genetics ; Salmonella -- Genetics
    ISSN: 00278424
    E-ISSN: 1091-6490
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    In: Molecular Microbiology, December 2011, Vol.82(6), pp.1305-1310
    Description: RNase E is an essential endoribonuclease with a preference for RNA substrates with 5′‐monophosphate ends. Primary transcripts, which have 5′ triphosphate ends, are thus protected from RNase E. Their conversion to 5′‐monophosphate transcripts by RppH is a prerequisite for RNase E‐mediated processing and degradation. 5′‐monophosphate recognition involves binding to a subdomain in the catalytic core of RNase E known as the 5′ sensor. There are, however, transcripts that can be attacked directly by RNase E in a 5′‐end‐independent pathway. Direct entry involves elements outside of the catalytic domain that are located in the carboxyl terminal half (CTH) of RNase E. Strains harbouring alleles that express variants of RNase E in which 5′ sensing () or direct entry () are inactivated, are viable. However, the / and / combinations are synthetic lethal suggesting that the essential function(s) of RNase E requires at least one of these pathways to be active. A striking result is the demonstration that mutations affecting Rho‐dependent transcription termination can overcome synthetic lethality by a pathway that requires RNase H. It is hypothesized that R‐loop formation and RNase H cleavage substitute for RNase E‐dependent RNA processing and mRNA degradation.
    Keywords: Messenger Rna ; Ribonuclease;
    ISSN: 0950-382X
    E-ISSN: 1365-2958
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    In: International Journal of Cancer, 01 November 2015, Vol.137(9), pp.2133-2138
    Description: Long‐term recurrences of colon cancer raised questions about the possible benefit of prolonging the recommended active 5‐year surveillance. The aim of this study was to determine, for the first time, the incidence and patterns of late 10‐year recurrence following curative resection of colon cancer. Data were obtained from two French digestive cancer registries. A total of 3,622 patients under 85 years resected for cure for colon cancer diagnosed between 1985 and 2000 were included. Information regarding recurrences was actively collected. Cumulative failure rates at 10 years were estimated using Kaplan–Meier estimates corrected by cause‐specific hazards, and multivariable analysis was performed using a model for the subdistribution of a competing risk proposed by Fine and Gray. The overall cumulative recurrence rate between 5 and 10 years after initial surgery was 2.9% for local recurrence and 4.3% for distant metastasis. Among men with no recurrence 5 years after diagnosis of colon cancer, 1 in 12 developed a recurrence between 5 and 10 years, and the corresponding cumulative rate was 7.8%. The frequency was 1 in 19 for women, corresponding to a cumulative rate of 5.2%. In the multivariate analysis, non‐emergency diagnostic feature, female sex and age under 75 were associated with a lower risk of recurrence. Stage at diagnosis was not a predictor of late recurrence. Late recurrence after colon cancer resection with curative intent can occur. A regular clinical follow‐up is necessary to detect early signs of possible recurrence. What's new? The recurrence of colon cancer more than 5 years following surgery for curative resection is a significant concern for patients. Yet, little is known about the epidemiology of late recurrence for colon cancer. Here, among more than 3,600 patients who underwent resection with intention to cure, 1 man in every 12 and 1 woman in every 19 was affected by late recurrence, defined as the return of colon cancer between 5 and 10 years after surgery. The findings suggest that regular follow‐up beyond 5 years may be needed in order to catch recurrence in a timely manner.
    Keywords: Colon Cancer ; Long‐Term Recurrence ; Distant Metastases ; Local Recurrence ; Cancer Registry
    ISSN: 0020-7136
    E-ISSN: 1097-0215
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    In: Nature, 2006, Vol.440(7088), p.1157
    Description: Lateral DNA transfer--the movement of genetic traits between bacteria--has a profound impact on genomic evolution and speciation. The efficiency with which bacteria incorporate genetic information reflects their capacity to adapt to changing environmental conditions. Integron integrases are proteins that mediate site-specific DNA recombination between a proximal primary site (attI) and a secondary target site (attC) found within mobile gene cassettes encoding resistance or virulence factors. The lack of sequence conservation among attC sites has led to the hypothesis that a sequence-independent structural recognition determinant must exist within attC. Here we report the crystal structure of an integron integrase bound to an attC substrate. The structure shows that DNA target site recognition and high-order synaptic assembly are not dependent on canonical DNA but on the position of two flipped-out bases that interact in cis and in trans with the integrase. These extrahelical bases, one of which is required for recombination in vivo, originate from folding of the bottom strand of attC owing to its imperfect internal dyad symmetry. The mechanism reported here supports a new paradigm for how sequence-degenerate single-stranded genetic material is recognized and exchanged between bacteria. [PUBLICATION ]
    Keywords: Bacteria ; Deoxyribonucleic Acid ; Genetics ; Recognition ; Conservation ; Cassettes ; Strands ; Encoding ; General and Nonclassified (MD) ; General and Nonclassified (EC) ; General and Nonclassified (Ed) ; General and Nonclassified (Ep) ; Surveying, Theory, and Analysis (CE) ; Design Principles, Theory, and Analysis (Mt) ; Computing Milieux (General) (Ci) ; Electronics and Communications Milieux (General) (Ea) ; Solid State Milieux (General) (So) ; Article;
    ISSN: 0028-0836
    E-ISSN: 14764687
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    In: American Journal of Gastroenterology, 2012, Vol.107(9), pp.1443-1444
    Keywords: Chemical Sciences ; Organic Chemistry ; Medicine;
    ISSN: 0002-9270
    E-ISSN: 15720241
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Language: English
    In: Nucleic acids research, 01 September 2012, Vol.40(17), pp.8361-70
    Description: Site-specific recombination catalyzed by tyrosine recombinases follows a common pathway consisting of two consecutive strand exchanges. The first strand exchange generates a Holliday junction (HJ), which is resolved by a second strand exchange. In integrons, attC sites recombine as folded single-stranded substrates. Only one of the two attC site strands, the bottom one, is efficiently bound and cleaved by the integrase during the insertion of gene cassettes at the double-stranded attI site. Due to the asymmetry of this complex, a second strand exchange on the attC bottom strand (bs) would form linearized abortive recombination products. We had proposed that HJ resolution would rely on an uncharacterized mechanism, probably replication. Using an attC site carried on a plasmid with each strand specifically tagged, we followed the destiny of each strand after recombination. We demonstrated that only one strand, the one carrying the attC bs, is exchanged. Furthermore, we show that the recombination products contain the attC site bs and its entire de novo synthesized complementary strand. Therefore, we demonstrate the replicative resolution of single-strand recombination in integrons and rule out the involvement of a second strand exchange of any kind in the attC×attI reaction.
    Keywords: DNA Replication ; Integrons ; Recombination, Genetic
    ISSN: 03051048
    E-ISSN: 1362-4962
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Language: English
    In: Biochimica et biophysica acta, 2013, Vol.1829(6-7), pp.514-22
    Description: Bacterial transcripts each have a characteristic half-life, suggesting that the processes of RNA degradation work in an active and selective manner. Moreover, the processes are well controlled, thereby ensuring that degradation is orderly and coordinated. Throughout much of the bacterial kingdom, RNA degradation processes originate through the actions of assemblies of key RNA enzymes, known as RNA degradosomes. Neither conserved in composition, nor unified by common evolutionary ancestry, RNA degradosomes nonetheless can be found in divergent bacterial lineages, implicating a common requirement for the co-localisation of RNA metabolic activities. We describe how the cooperation of components in the representative degradosome of Escherichia coli may enable controlled access to transcripts, so that they have defined and programmable lifetimes. We also discuss how this cooperation contributes to precursor processing and to the riboregulation of intricate post-transcriptional networks in the control of gene expression. The E. coli degradosome interacts with the cytoplasmic membrane, and we discuss how this interaction may spatially organise the assembly and contribute to subunit cooperation and substrate capture. This article is part of a Special Issue entitled: RNA Decay mechanisms.
    Keywords: Multienzyme Complexes ; Polyribonucleotide Nucleotidyltransferase ; RNA Helicases ; RNA Stability ; Endoribonucleases -- Genetics ; RNA, Bacterial -- Genetics
    ISSN: 0006-3002
    E-ISSN: 18782434
    Source: MEDLINE/PubMed (U.S. National Library of Medicine)
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    In: Colorectal Cancer, April 2013, Vol.2(2), p.145-153
    Description: SUMMARY  The negative impact of regional lymph node metastasis on survival from nonmetastatic colorectal cancers is proportional to the number of nodes harvested. A thorough lymph node examination by the pathologist is essential for accurate staging. Recommendations in the USA and Europe stipulate that a minimum of 12–15 lymph nodes must be examined to accurately predict regional node negativity. The prognostic separation for stage III colorectal cancer obtained by the lymph node ratio is superior to that of the absolute number of positive nodes. The extent of mesenteric resection, pathologic technique, age or tumor location may influence lymph node yield. In the future, biological significance and clinical impact on outcome of very small amounts of tumor in regional nodes could help in staging patients. The current data are considered insufficient to recommend either the routine examination of multiple tissue levels of paraffin blocks or the use of special/ancillary techniques.
    Keywords: Lymphatic Metastasis -- Research ; Colorectal Cancer -- Care And Treatment ; Colorectal Cancer -- Research;
    ISSN: 1758-194X
    E-ISSN: 1758-1958
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Language: English
    In: Colorectal Cancer, April, 2013, Vol.2(2), p.145(9)
    Description: SUMMARY The negative impact of regional lymph node metastasis on survival from nonmetastatic colorectal cancers is proportional to the number of nodes harvested. A thorough lymph node examination by the pathologist is essential for accurate staging. Recommendations in the USA and Europe stipulate that a minimum of 12-15 lymph nodes must be examined to accurately predict regional node negativity. The prognostic separation for stage III colorectal cancer obtained by the lymph node ratio is superior to that of the absolute number of positive nodes. The extent of mesenteric resection, pathologic technique, age or tumor location may influence lymph node yield. In the future, biological significance and clinical impact on outcome of very small amounts of tumor in regional nodes could help in staging patients. The current data are considered insufficient to recommend either the routine examination of multiple tissue levels of paraffin blocks or the use of special/ancillary techniques.
    Keywords: Lymphatic Metastasis -- Research ; Colorectal Cancer -- Care And Treatment ; Colorectal Cancer -- Research
    ISSN: 1758-194X
    Source: Cengage Learning, Inc.
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Language: English
    In: Digestive and Liver Disease, August 2013, Vol.45(8), pp.687-691
    Description: European guidelines recommend adjuvant chemotherapy for stage III colon cancer but not for stage II. To determine the extent to which adjuvant chemotherapy was used in Italy and France. A common retrospective database of 2186 colon cancers diagnosed between 2003 and 2005 was analysed according to age, stage and presenting features. 38.9% of patients with stage II and 64.6% with stage III received chemotherapy in Italy, 21.7% and 65.1% in France. For stage II, the association between country and chemotherapy was only significant in patients diagnosed out of emergency (OR : 3.05 [2.12–4.37], 〈 0.001) whereas patients diagnosed in emergency were as likely to receive chemotherapy in both countries. For stage III, there was a trend to a higher administration of chemotherapy for elderly patients in France compared to Italy. French patients were more likely than Italian to receive chemotherapy (OR: 1.91[1.32–2.78], = 0.001). Chemotherapy for stage III colon cancer was as extensively used in Italy as in France for young patients. Its administration could be increased in patients over 75. Stage II patients with a lower risk of relapse received chemotherapy more often in Italy than in France.
    Keywords: Adjuvant Chemotherapy ; Cancer Registry ; Colon Cancer ; Stage II and III ; Medicine ; Anatomy & Physiology
    ISSN: 1590-8658
    E-ISSN: 1878-3562
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages