ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Publication Date: 2010-04-29
    Description: The nucleolytic activity of animal Argonaute proteins is deeply conserved, despite its having no obvious role in microRNA-directed gene regulation. In mice, Ago2 (also known as Eif2c2) is uniquely required for viability, and only this family member retains catalytic competence. To investigate the evolutionary pressure to conserve Argonaute enzymatic activity, we engineered a mouse with catalytically inactive Ago2 alleles. Homozygous mutants died shortly after birth with an obvious anaemia. Examination of microRNAs and their potential targets revealed a loss of miR-451, a small RNA important for erythropoiesis. Though this microRNA is processed by Drosha (also known as Rnasen), its maturation does not require Dicer. Instead, the pre-miRNA becomes loaded into Ago and is cleaved by the Ago catalytic centre to generate an intermediate 3' end, which is then further trimmed. Our findings link the conservation of Argonaute catalysis to a conserved mechanism of microRNA biogenesis that is important for vertebrate development.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2995450/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2995450/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Cheloufi, Sihem -- Dos Santos, Camila O -- Chong, Mark M W -- Hannon, Gregory J -- P01 CA013106/CA/NCI NIH HHS/ -- P01 CA013106-38/CA/NCI NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2010 Jun 3;465(7298):584-9. doi: 10.1038/nature09092.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Cold Spring Harbor Laboratory, Watson School of Biological Sciences, Howard Hughes Medical Institute, Cold Spring Harbor, New York 11724, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20424607" target="_blank"〉PubMed〈/a〉
    Keywords: Alleles ; Anemia/genetics/metabolism ; Animals ; Argonaute Proteins ; Base Sequence ; *Biocatalysis ; Embryo, Mammalian/embryology/metabolism ; Eukaryotic Initiation Factor-2/genetics/*metabolism ; Homozygote ; MicroRNAs/*biosynthesis ; Molecular Sequence Data ; Ribonuclease III/metabolism
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2008-03-28
    Description: T helper cells that produce IL-17 (T(H)17 cells) promote autoimmunity in mice and have been implicated in the pathogenesis of human inflammatory diseases. At mucosal surfaces, T(H)17 cells are thought to protect the host from infection, whereas regulatory T (T(reg)) cells control immune responses and inflammation triggered by the resident microflora. Differentiation of both cell types requires transforming growth factor-beta (TGF-beta), but depends on distinct transcription factors: RORgammat (encoded by Rorc(gammat)) for T(H)17 cells and Foxp3 for T(reg) cells. How TGF-beta regulates the differentiation of T cells with opposing activities has been perplexing. Here we demonstrate that, together with pro-inflammatory cytokines, TGF-beta orchestrates T(H)17 cell differentiation in a concentration-dependent manner. At low concentrations, TGF-beta synergizes with interleukin (IL)-6 and IL-21 (refs 9-11) to promote IL-23 receptor (Il23r) expression, favouring T(H)17 cell differentiation. High concentrations of TGF-beta repress IL23r expression and favour Foxp3+ T(reg) cells. RORgammat and Foxp3 are co-expressed in naive CD4+ T cells exposed to TGF-beta and in a subset of T cells in the small intestinal lamina propria of the mouse. In vitro, TGF-beta-induced Foxp3 inhibits RORgammat function, at least in part through their interaction. Accordingly, lamina propria T cells that co-express both transcription factors produce less IL-17 (also known as IL-17a) than those that express RORgammat alone. IL-6, IL-21 and IL-23 relieve Foxp3-mediated inhibition of RORgammat, thereby promoting T(H)17 cell differentiation. Therefore, the decision of antigen-stimulated cells to differentiate into either T(H)17 or T(reg) cells depends on the cytokine-regulated balance of RORgammat and Foxp3.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2597437/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2597437/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Zhou, Liang -- Lopes, Jared E -- Chong, Mark M W -- Ivanov, Ivaylo I -- Min, Roy -- Victora, Gabriel D -- Shen, Yuelei -- Du, Jianguang -- Rubtsov, Yuri P -- Rudensky, Alexander Y -- Ziegler, Steven F -- Littman, Dan R -- AI48779/AI/NIAID NIH HHS/ -- R01 AI048779/AI/NIAID NIH HHS/ -- R01 AI048779-05/AI/NIAID NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2008 May 8;453(7192):236-40. doi: 10.1038/nature06878. Epub 2008 Mar 26.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, New York, New York 10016, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18368049" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Cell Differentiation/drug effects ; Cell Line ; Cells, Cultured ; Forkhead Transcription Factors/genetics/*metabolism ; Gene Expression Regulation/drug effects ; Humans ; Interleukin-17/biosynthesis/genetics/*metabolism ; Mice ; Mice, Inbred C57BL ; Nuclear Receptor Subfamily 1, Group F, Member 3 ; Receptors, Interleukin/genetics/metabolism ; Receptors, Retinoic Acid/*antagonists & inhibitors/genetics/metabolism ; Receptors, Thyroid Hormone/*antagonists & inhibitors/genetics/metabolism ; T-Lymphocytes, Helper-Inducer/*cytology/*drug effects/metabolism ; Transforming Growth Factor beta/*pharmacology
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...