keyword
MENU ▼
Read by QxMD icon Read
search

Aid deaminase

keyword
https://www.readbyqxmd.com/read/28634398/mutations-in-human-aid-differentially-affect-its-ability-to-deaminate-cytidine-and-5-methylcytidine-in-ssdna-substrates-in-vitro
#1
Lucyna Budzko, Paulina Jackowiak, Karol Kamel, Joanna Sarzynska, Janusz M Bujnicki, Marek Figlerowicz
Activation-induced cytidine deaminase (AID) is known for its established role in antibody production. AID induces the diversification of antibodies by deaminating deoxycytidine (C) within immunoglobulin genes. The capacity of AID to deaminate 5-methyldeoxycytidine (5 mC) and/or 5-hydroxymethyldeoxycytidine (5 hmC), and consequently AID involvement in active DNA demethylation, is not fully resolved. For instance, structural determinants of AID activity on different substrates remain to be identified. To better understand the latter issue, we tested how mutations in human AID (hAID) influence its ability to deaminate C, 5 mC, and 5 hmC in vitro...
June 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28630076/what-are-the-primary-limitations-in-b-cell-affinity-maturation-and-how-much-affinity-maturation-can-we-drive-with-vaccination-is-affinity-maturation-a-self-defeating-process-for-eliciting-broad-protection
#2
Christopher T Stamper, Patrick C Wilson
Vaccinations are one of the greatest success stories of modern medicine, saving millions of lives since their widespread adoption. However, several diseases continue to elude highly effective vaccination strategies. Chief among these are human immunodeficiency virus (HIV) and influenza (flu), both of which will require vaccines that can guide the creation of highly mutated, broadly neutralizing antibodies (bnAbs). The generation of bnAbs is hindered by our inability to effectively drive the high levels of affinity maturation required to achieve them in a large number of cells...
June 19, 2017: Cold Spring Harbor Perspectives in Biology
https://www.readbyqxmd.com/read/28626219/base-excision-repair-proteins-couple-activation-induced-cytidine-deaminase-and-endonuclease-g-during-replication-stress-induced-mll-destabilization
#3
B Gole, E Mian, M Rall, L Wiesmüller
The breakpoint cluster region of the MLL gene (MLLbcr) is frequently rearranged in therapy-related and infant acute leukaemia, but the destabilizing mechanism is poorly understood. We recently proposed that DNA replication stress results in MLLbcr cleavage via Endonuclease G (EndoG) and represents the common denominator of genotoxic therapy-induced MLL destabilization. Here we performed a siRNA screen for new factors involved in replication stress-induced MLL rearrangements employing an EGFP-based reporter system...
June 19, 2017: Leukemia: Official Journal of the Leukemia Society of America, Leukemia Research Fund, U.K
https://www.readbyqxmd.com/read/28621910/allospecific-memory-b-cell-responses-are-dependent-on-autophagy
#4
Miguel Fribourg, Jie Ni, F Nina Papavasiliou, Zhenyu Yue, Peter S Heeger, Jeremy S Leventhal
Long-lived, donor-reactive memory B cells (Bmem) can produce alloantibodies that mediate transplant injury. Autophagy, an intrinsic mechanism of cell organelle/component recycling, is required for Bmem survival in infectious and model antigen systems but whether autophagy impacts alloreactive Bmem is unknown. We studied mice with an inducible yellow fluorescent protein (YFP) reporter expressed under the Activation-Induced Cytidine Deaminase (AID) promoter active in B cells undergoing germinal center reactions...
June 16, 2017: American Journal of Transplantation
https://www.readbyqxmd.com/read/28589361/the-aid-cre-ert2-model-a-tool-for-monitoring-b-cell-immune-responses-and-generating-selective-hybridomas
#5
Simon Le Gallou, Takuya Nojima, Daisuke Kitamura, Jean-Claude Weill, Claude-Agnès Reynaud
Expression of activation-induced cytidine deaminase (AID) is the hallmark of B cells engaged in an immune response in germinal centers. We designed an inducible fate-mapping reporter mouse in which AID-expressing B cells could be timely and irreversibly marked, by knockin at the Aicda locus of a tamoxifen-inducible Cre recombinase. This mouse model allows notably for the long-term follow-up of memory B cells and plasma cells engaged in an immune response. We describe here a protocol to generate hybridomas from small memory subsets that can be easily traced and identified in this mouse line through Cre-activated fluorescent reporters...
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/28588701/aberrant-expression-of-aid-and-aid-activators-of-nf-%C3%AE%C2%BAb-and-pax5-is-irrelevant-to-ebv-associated-gastric-cancers-but-is-associated-with-carcinogenesis-in-certain-ebv-non-associated-gastric-cancers
#6
Takashi Mohri, Keiko Nagata, Satoshi Kuwamoto, Michiko Matsushita, Hirotsugu Sugihara, Masako Kato, Yasushi Horie, Ichiro Murakami, Kazuhiko Hayashi
Epstein-Barr virus-associated gastric carcinoma (EBVaGC) is a distinct subtype of gastric cancer characterized by clinicopathological features including lymphoepithelioma-like histology. Aberrant expression of activation-induced cytidine deaminase (AID) as a genomic modulator was demonstrated through pathogen-related nuclear factor κB (NF-κB) signaling in Helicobacter pylori-associated gastric cancer. To elucidate whether or not AID expression is relevant to carcinogenesis in EBVaGC, immunohistochemical expression of AID and AID-regulatory factors between EBVaGC and EBV-non-associated gastric carcinoma (GC) were evaluated, each using 15 cases of GC with lymphoid stroma (GCLS) and other types of GC...
June 2017: Oncology Letters
https://www.readbyqxmd.com/read/28575114/early-derivation-of-igm-memory-cells-and-bone-marrow-plasmablasts
#7
Amber M Papillion, Kevin J Kenderes, Jennifer L Yates, Gary M Winslow
IgM memory cells are recognized as an important component of B cell memory in mice and humans. Our studies of B cells elicited in response to ehrlichial infection identified a population of CD11c-positive IgM memory cells, and an IgM bone marrow antibody-secreting cell population. The origin of these cells was unknown, although an early T-independent spleen CD11c- and T-bet-positive IgM plasmablast population precedes both, suggesting a linear relationship. A majority of the IgM memory cells detected after day 30 post-infection, also T-bet-positive, had undergone somatic hypermutation, indicating they expressed activation-induced cytidine deaminase (AID)...
2017: PloS One
https://www.readbyqxmd.com/read/28574479/r-loops-in-the-regulation-of-antibody-gene-diversification
#8
REVIEW
Rushad Pavri
For nearly three decades, R loops have been closely linked with class switch recombination (CSR), the process that generates antibody isotypes and that occurs via a complex cascade initiated by transcription-coupled mutagenesis in switch recombination sequences. R loops form during transcription of switch recombination sequences in vitro and in vivo, and there is solid evidence that R loops are required for efficient class switching. The classical model of R loops posits that they boost mutation rates by generating stable and long tracts of single-stranded DNA that serve as the substrate for activation induced deaminase (AID), the enzyme that initiates the CSR reaction cascade by co-transcriptionally mutating ssDNA in switch recombination sequences...
June 2, 2017: Genes
https://www.readbyqxmd.com/read/28544233/bcl6-overexpression-alters-gene-expression-profile-in-a-myeloma-cell-line-and-is-associated-with-decreased-dna-damage-response
#9
Kenichi Tahara, Makiko Takizawa, Arito Yamane, Yohei Osaki, Takuma Ishizaki, Takeki Mitsui, Akihiko Yokohama, Takayuki Saitoh, Norifumi Tsukamoto, Morio Matsumoto, Hirokazu Murakami, Yoshihisa Nojima, Hiroshi Handa
BCL6 attenuates DNA damage response (DDR) through gene repression and facilitates tolerance to genomic instability during immunoglobulin affinity maturation in germinal center (GC) B cells. Although BCL6 expression is repressed through normal differentiation of GC B cells into plasma cells, a recent study showed the ectopic expression of BCL6 in primary multiple myeloma (MM) cells. However, the functional roles of BCL6 in MM cells are largely unknown. Here, we report that overexpression of BCL6 in a MM cell line, KMS12PE, induced transcriptional repression of ataxia telangiectasia mutated (ATM), a DDR signaling kinase, which was associated with a reduction in γH2AX formation after DNA damage...
May 23, 2017: Cancer Science
https://www.readbyqxmd.com/read/28541550/integrity-of-immunoglobulin-variable-region-is-supported-by-ganp-during-aid-induced-somatic-hypermutation-in-germinal-center-b-cells
#10
Mohammed Mansour Abbas Eid, Mayuko Shimoda, Shailendra Kumar Singh, Sarah Ameen Almofty, Phuong Pham, Myron F Goodman, Kazuhiko Maeda, Nobuo Sakaguchi
Immunoglobulin (Ig) affinity maturation depends on somatic hypermutation (SHM) in variable (V) regions initiated by activation-induced cytidine deaminase (AID). AID induces transition mutations by C→U deamination on both strands, causing C:G→T:A. Error-prone repairs of U by base excision and mismatch repairs create transversion mutations at C/G and mutations at A/T sites. In Neuberger's model, it remained to clarify how transition/transversion repair is regulated. We investigate role of AID-interacting GANP (germinal-center associated nuclear protein) in IgV SHM profile...
May 24, 2017: International Immunology
https://www.readbyqxmd.com/read/28535205/a-transcriptional-serenaid-the-role-of-noncoding-rnas-in-class-switch-recombination
#11
William T Yewdell, Jayanta Chaudhuri
During an immune response, activated B cells may undergo class switch recombination (CSR), a molecular rearrangement that allows B cells to switch from expressing IgM and IgD to a secondary antibody heavy chain isotype such as IgG, IgA, or IgE. Secondary antibody isotypes provide the adaptive immune system with distinct effector functions to optimally combat various pathogens. CSR occurs between repetitive DNA elements within the immunoglobulin heavy chain (Igh) locus, termed switch (S) regions, and requires the DNA modifying enzyme activation-induced cytidine deaminase (AID)...
May 23, 2017: International Immunology
https://www.readbyqxmd.com/read/28490810/establishment-of-induced-pluripotent-stem-cells-from-normal-b-cells-and-inducing-aid-expression-in-their-differentiation-into-hematopoietic-progenitor-cells
#12
Fumihiko Kawamura, Makoto Inaki, Atsushi Katafuchi, Yu Abe, Naohiro Tsuyama, Yumiko Kurosu, Aki Yanagi, Mitsunori Higuchi, Satoshi Muto, Takumi Yamaura, Hiroyuki Suzuki, Hideyoshi Noji, Shinichi Suzuki, Mitsuaki A Yoshida, Megumi Sasatani, Kenji Kamiya, Masafumi Onodera, Akira Sakai
B cell derived induced pluripotent stem cells (BiPSCs) were recently established from peripheral blood B cells by the simultaneous transfection of Yamanaka factors (Oct3/4, Sox2, Klf4, c-Myc) and C/EBPα using a Sendai virus vector. Here, using a different method, we established BiPSCs with immunoglobulin heavy chain (IgH) gene rearrangement from normal B cells purified from lymph nodes. The critical points of our method are pre-stimulation of B cells with IL-21 and CD40-ligand (CD40L), followed by consecutive transfection of highly concentrated Yamanaka factors using a retroviral vector...
May 10, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28479091/family-wide-comparative-analysis-of-cytidine-and-methylcytidine-deamination-by-eleven-human-apobec-proteins
#13
Fumiaki Ito, Yang Fu, Shen-Chi A Kao, Hanjing Yang, Xiaojiang S Chen
Apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like (APOBEC) proteins are a family of cytidine deaminases involved in various important biological processes such as antibody diversification/maturation, restriction of viral infection, and generation of somatic mutations. Catalytically active APOBEC proteins execute their biological functions mostly through deaminating cytosine (C) to uracil on single-stranded DNA/RNA. Activation-induced cytidine deaminase, one of the APOBEC members, was reported to deaminate methylated cytosine (mC) on DNA, and this mC deamination was proposed to be involved in the demethylation of mC for epigenetic regulation...
May 4, 2017: Journal of Molecular Biology
https://www.readbyqxmd.com/read/28472485/apobec3a-efficiently-deaminates-methylated-but-not-tet-oxidized-cytosine-bases-in-dna
#14
Emily K Schutsky, Christopher S Nabel, Amy K F Davis, Jamie E DeNizio, Rahul M Kohli
AID/APOBEC family enzymes are best known for deaminating cytosine bases to uracil in single-stranded DNA, with characteristic sequence preferences that can produce mutational signatures in targets such as retroviral and cancer cell genomes. These deaminases have also been proposed to function in DNA demethylation via deamination of either 5-methylcytosine (mC) or TET-oxidized mC bases (ox-mCs), which include 5-hydroxymethylcytosine, 5-formylcytosine and 5-carboxylcytosine. One specific family member, APOBEC3A (A3A), has been shown to readily deaminate mC, raising the prospect of broader activity on ox-mCs...
May 2, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28462376/regulation-of-gastric-metaplasia-dysplasia-and-neoplasia-by-bone-morphogenetic-protein-signaling
#15
REVIEW
Andrea Todisco
The bone morphogenetic proteins, (BMP)s are regulatory peptides that have significant effects on the growth and differentiation of gastrointestinal tissues. In addition, the BMPs have been shown to exert anti-inflammatory actions in the gut and to negatively regulate the growth of gastric neoplasms. The role of BMP signaling in the regulation of gastric metaplasia, dysplasia and neoplasia has been poorly characterized. Transgenic expression in the mouse stomach of the BMP inhibitor noggin leads to decreased parietal cell number, increased epithelial cell proliferation, and to the emergence of SPEM...
May 2017: Cellular and Molecular Gastroenterology and Hepatology
https://www.readbyqxmd.com/read/28461573/genetic-and-small-molecule-disruption-of-the-aid-rad51-axis-similarly-protects-nonobese-diabetic-mice-from-type-1-diabetes-through-expansion-of-regulatory-b-lymphocytes
#16
Jeremy J Ratiu, Jeremy J Racine, Muneer G Hasham, Qiming Wang, Jane A Branca, Harold D Chapman, Jing Zhu, Nina Donghia, Vivek Philip, William H Schott, Clive Wasserfall, Mark A Atkinson, Kevin D Mills, Caroline M Leeth, David V Serreze
B lymphocytes play a key role in type 1 diabetes (T1D) development by serving as a subset of APCs preferentially supporting the expansion of autoreactive pathogenic T cells. As a result of their pathogenic importance, B lymphocyte-targeted therapies have received considerable interest as potential T1D interventions. Unfortunately, the B lymphocyte-directed T1D interventions tested to date failed to halt β cell demise. IgG autoantibodies marking humans at future risk for T1D indicate that B lymphocytes producing them have undergone the affinity-maturation processes of class switch recombination and, possibly, somatic hypermutation...
June 1, 2017: Journal of Immunology: Official Journal of the American Association of Immunologists
https://www.readbyqxmd.com/read/28445143/the-igh-locus-relocalizes-to-a-recombination-compartment-in-the-perinucleolar-region-of-differentiating-b-lymphocytes
#17
Andrey Pichugin, Olga V Iarovaia, Alexey Gavrilov, Ilya Sklyar, Natalja Barinova, Aleksandr Barinov, Evgeny Ivashkin, Gersende Caron, Said Aoufouchi, Sergey V Razin, Thierry Fest, Marc Lipinski, Yegor S Vassetzky
The immunoglobulin heavy chain (IGH) gene loci are subject to specific recombination events during B-cell differentiation including somatic hypermutation and class switch recombination which mark the end of immunoglobulin gene maturation in germinal centers of secondary lymph nodes. These two events rely on the activity of activation-induced cytidine deaminase (AID) which requires DNA double strand breaks be created, a potential danger to the cell. Applying 3D-fluorescence in situ hybridization coupled with immunofluorescence staining to a previously described experimental system recapitulating normal B-cell differentiation ex vivo, we have kinetically analyzed the radial positioning of the two IGH gene loci as well as their proximity with the nucleolus, heterochromatin and γH2AX foci...
June 20, 2017: Oncotarget
https://www.readbyqxmd.com/read/28439266/a-novel-regulator-of-activation-induced-cytidine-deaminase-apobecs-in-immunity-and-cancer-schr%C3%A3-dinger-s-catalytic-pocket
#18
REVIEW
Justin J King, Mani Larijani
Activation-induced cytidine deaminase (AID) and its relative APOBEC3 cytidine deaminases boost immune response by mutating immune or viral genes. Because of their genome-mutating activities, AID/APOBECs are also drivers of tumorigenesis. Due to highly charged surfaces, extensive non-specific protein-protein/nucleic acid interactions, formation of polydisperse oligomers, and general insolubility, structure elucidation of these proteins by X-ray crystallography and NMR has been challenging. Hence, almost all available AID/APOBEC structures are of mutated and/or truncated versions...
2017: Frontiers in Immunology
https://www.readbyqxmd.com/read/28429755/opossum-apobec1-is-a-dna-mutator-with-retrovirus-and-retroelement-restriction-activity
#19
Terumasa Ikeda, Mayuko Shimoda, Diako Ebrahimi, John L VandeBerg, Reuben S Harris, Atsushi Koito, Kazuhiko Maeda
APOBEC3s (A3s) are single-stranded DNA cytosine deaminases that provide innate immune defences against retroviruses and mobile elements. A3s are specific to eutherian mammals because no direct homologs exist at the syntenic genomic locus in metatherian (marsupial) or prototherian (monotreme) mammals. However, the A3s in these species have the likely evolutionary precursors, the antibody gene deaminase AID and the RNA/DNA editing enzyme APOBEC1 (A1). Here, we used cell culture-based assays to determine whether opossum A1 restricts the infectivity of retroviruses including human immunodeficiency virus type 1 (HIV-1) and the mobility of LTR/non-LTR retrotransposons...
April 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28407558/cd11b-regulates-antibody-class-switching-via-induction-of-aid
#20
Seohyun Park, Hyunsub Sim, Hye-In Kim, Daecheol Jeong, Guang Wu, Soo Young Cho, Young Seek Lee, Hyung-Joo Kwon, Keunwook Lee
The integrin CD11b, which is encoded by the integrin subunit alpha M (ITGAM), is primarily expressed on the surface of innate immune cells. Genetic variations in ITGAM are among the strongest risk factors for systemic lupus erythematosus, an autoimmune disease characterized by the presence of autoantibodies. However, the regulatory function of CD11b in the antibody responses remains unclear. Here, we report the induction of CD11b in activated B2 B cells and define its unexpected role in immunoglobulin heavy chain class switch recombination (CSR)...
April 10, 2017: Molecular Immunology
keyword
keyword
58124
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"