Ranjan Sen

Summary

Affiliation: National Institutes of Health
Country: USA

Publications

  1. pmc NF-kappaB and the immunoglobulin kappa gene enhancer
    Ranjan Sen
    Lab of Cellular and Molecular Biology, National Institute on Aging, 5600 Nathan Shock Dr, Baltimore, MD 21224, USA
    J Exp Med 200:1099-102. 2004
  2. pmc Memories of lost enhancers
    Ranjan Sen
    Laboratory of Cellular and Molecular Biology, National Institute of Aging, Baltimore, Maryland 21224, USA
    Genes Dev 24:973-9. 2010
  3. ncbi request reprint Control of B lymphocyte apoptosis by the transcription factor NF-kappaB
    Ranjan Sen
    Laboratory of Cellular and Molecular Biology, National Institute on Aging, Baltimore, Maryland 21224, USA
    Immunity 25:871-83. 2006
  4. pmc Localized DNA demethylation at recombination intermediates during immunoglobulin heavy chain gene assembly
    Roza Selimyan
    Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
    PLoS Biol 11:e1001475. 2013
  5. pmc Localized epigenetic changes induced by DH recombination restricts recombinase to DJH junctions
    Ramesh Subrahmanyam
    Laboratory of Molecular Biology and Immunology, National Institute on Aging, US National Institutes of Health, Baltimore, Maryland, USA
    Nat Immunol 13:1205-12. 2012
  6. pmc A 220-nucleotide deletion of the intronic enhancer reveals an epigenetic hierarchy in immunoglobulin heavy chain locus activation
    Tirtha Chakraborty
    Laboratory of Cellular and Molecular Biology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
    J Exp Med 206:1019-27. 2009
  7. doi request reprint Activation of 12/23-RSS-dependent RAG cleavage by hSWI/SNF complex in the absence of transcription
    Hansen Du
    Laboratory of Cellular and Molecular Biology, National Institute on Aging, Baltimore, MD 21224, USA
    Mol Cell 31:641-9. 2008
  8. pmc A plant homeodomain in RAG-2 that binds Hypermethylated lysine 4 of histone H3 is necessary for efficient antigen-receptor-gene rearrangement
    Yun Liu
    Department of Molecular Biology and Genetics, Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
    Immunity 27:561-71. 2007
  9. pmc Two forms of loops generate the chromatin conformation of the immunoglobulin heavy-chain gene locus
    Changying Guo
    Gene Regulation Section, Laboratory of Molecular Biology and Immunology, National Institute on Aging, Baltimore, MD 21224, USA
    Cell 147:332-43. 2011
  10. pmc Immunoglobulin switch mu sequence causes RNA polymerase II accumulation and reduces dA hypermutation
    Deepa Rajagopal
    Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
    J Exp Med 206:1237-44. 2009

Collaborators

Detail Information

Publications47

  1. pmc NF-kappaB and the immunoglobulin kappa gene enhancer
    Ranjan Sen
    Lab of Cellular and Molecular Biology, National Institute on Aging, 5600 Nathan Shock Dr, Baltimore, MD 21224, USA
    J Exp Med 200:1099-102. 2004
    ..Here, I discuss the implications of the new observation that an NF-kappaB binding site-mutated enhancer in the correct biological context does not appear to affect kappa gene expression...
  2. pmc Memories of lost enhancers
    Ranjan Sen
    Laboratory of Cellular and Molecular Biology, National Institute of Aging, Baltimore, Maryland 21224, USA
    Genes Dev 24:973-9. 2010
    ..659-669) providing evidence of a transient requirement of an enhancer associated with the CD4 gene, we discuss possible mechanisms by which transcriptional memory can be propagated in the absence of enhancers...
  3. ncbi request reprint Control of B lymphocyte apoptosis by the transcription factor NF-kappaB
    Ranjan Sen
    Laboratory of Cellular and Molecular Biology, National Institute on Aging, Baltimore, Maryland 21224, USA
    Immunity 25:871-83. 2006
    ..In particular, the temporal patterns of NF-kappaB induction, differences between Rel family members, and the intersection between canonical and noncanonical signaling pathways in keeping B cells alive are discussed...
  4. pmc Localized DNA demethylation at recombination intermediates during immunoglobulin heavy chain gene assembly
    Roza Selimyan
    Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
    PLoS Biol 11:e1001475. 2013
    ..We propose that demethylation occurs after the first recombination step and may mark the junction for secondary recombination...
  5. pmc Localized epigenetic changes induced by DH recombination restricts recombinase to DJH junctions
    Ramesh Subrahmanyam
    Laboratory of Molecular Biology and Immunology, National Institute on Aging, US National Institutes of Health, Baltimore, Maryland, USA
    Nat Immunol 13:1205-12. 2012
    ..We propose that V(H) recombination is precise, because these changes did not extend to germline D(H) segments located 5' of the DJ(H) junction...
  6. pmc A 220-nucleotide deletion of the intronic enhancer reveals an epigenetic hierarchy in immunoglobulin heavy chain locus activation
    Tirtha Chakraborty
    Laboratory of Cellular and Molecular Biology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
    J Exp Med 206:1019-27. 2009
    ..These observations define Emu-independent and Emu-dependent phases of locus activation that reveal an unappreciated epigenetic hierarchy in tissue-specific gene expression...
  7. doi request reprint Activation of 12/23-RSS-dependent RAG cleavage by hSWI/SNF complex in the absence of transcription
    Hansen Du
    Laboratory of Cellular and Molecular Biology, National Institute on Aging, Baltimore, MD 21224, USA
    Mol Cell 31:641-9. 2008
    ..These observations demonstrate a direct role for cis-sequence-regulated local chromatin remodeling in RAG1/2-dependent initiation of V(D)J recombination...
  8. pmc A plant homeodomain in RAG-2 that binds Hypermethylated lysine 4 of histone H3 is necessary for efficient antigen-receptor-gene rearrangement
    Yun Liu
    Department of Molecular Biology and Genetics, Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
    Immunity 27:561-71. 2007
    ..Together, these findings are consistent with the interpretation that recognition of hypermethylated histone H3 K4 promotes efficient V(D)J recombination in vivo...
  9. pmc Two forms of loops generate the chromatin conformation of the immunoglobulin heavy-chain gene locus
    Changying Guo
    Gene Regulation Section, Laboratory of Molecular Biology and Immunology, National Institute on Aging, Baltimore, MD 21224, USA
    Cell 147:332-43. 2011
    ..Our observations provide a comprehensive view of the conformation of IgH alleles in pro-B cells and the mechanisms by which it is established...
  10. pmc Immunoglobulin switch mu sequence causes RNA polymerase II accumulation and reduces dA hypermutation
    Deepa Rajagopal
    Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
    J Exp Med 206:1237-44. 2009
    ..We propose that altered DNA structure in the switch region pauses RNA polymerase II and limits access of DNA polymerase eta during hypermutation...
  11. pmc Age-associated alterations in inducible gene transcription in human CD4+ T lymphocytes
    Arsun Bektas
    Laboratory of Molecular Biology and Immunology, National Institutes of Health, Baltimore, MD 21224, USA
    Aging (Albany NY) 5:18-36. 2013
    ..Our studies provide the first view of age-associated alteration of TCR-inducible gene expression in human CD4+ T cells...
  12. pmc Single round of antigen receptor signaling programs naive B cells to receive T cell help
    Bazarragchaa Damdinsuren
    Gene Regulation Section, Laboratory of Cellular and Molecular Biology, National Institute on Aging, Baltimore, MD 21224, USA
    Immunity 32:355-66. 2010
    ..We propose that transient BCR signals prime B cells to receive T cell help by increasing the probability of B-T encounter and creating a cellular environment that is hyper-responsive to CD40 signaling...
  13. doi request reprint RAGs' eye view of the immunoglobulin heavy chain gene locus
    Ramesh Subrahmanyam
    Gene Regulation Section, Laboratory of Cellular and Molecular Biology, National Institute on Aging, National Institutes of Health, 251 Bayview Blvd, Room 06C214, Baltimore, MD 21224, United States
    Semin Immunol 22:337-45. 2010
    ..The emerging picture shows that the IgH locus consists of independently regulated domains, each of which requires multiple levels of epigenetic changes to reach the fully activated state...
  14. pmc The requirement for pre-TCR during thymic differentiation enforces a developmental pause that is essential for V-DJβ rearrangement
    Karen S Hathcock
    Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
    PLoS ONE 6:e20639. 2011
    ..However, the requirement for pre-TCR signals and the exclusion of alternative stimuli such as CD28 enforce a developmental "pause" in early DN3 cells that is essential for productive TCRβ rearrangement to occur...
  15. pmc A histone-fold complex and FANCM form a conserved DNA-remodeling complex to maintain genome stability
    Zhijiang Yan
    Laboratory of Genetics, National Institute of Aging, National Institutes of Health, Baltimore, MD 21224, USA
    Mol Cell 37:865-78. 2010
    ..Thus, FANCM-MHF is an essential DNA-remodeling complex that protects replication forks from yeast to human...
  16. doi request reprint NF-κB function in B lymphocytes
    Mary Kaileh
    Gene Regulation Section, Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
    Immunol Rev 246:254-71. 2012
    ..We endeavor throughout to suggest mechanisms and implications of the wide-ranging observations that have been made and conclude by highlighting the need to understand NF-κB-mediated gene expression in more depth...
  17. doi request reprint Regulating antibody diversity: taming a mutagen
    Patricia J Gearhart
    Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Baltimore, MD 21224, USA
    Mol Cell 31:615-6. 2008
    ..2008) identified a protein that interacts with the activation-induced deaminase protein and affects somatic hypermutation, class switching, and gene conversion in immunoglobulin genes, possibly via the spliceosome transcription complex...
  18. doi request reprint Epigenetic features that regulate IgH locus recombination and expression
    Ramesh Subrahmanyam
    National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
    Curr Top Microbiol Immunol 356:39-63. 2012
    ..In this review we discuss the regulatory features of each step of IgH gene assembly and the role of epigenetic mechanisms in achieving regulatory precision...
  19. ncbi request reprint Repeat organization and epigenetic regulation of the DH-Cmu domain of the immunoglobulin heavy-chain gene locus
    Tirtha Chakraborty
    Laboratory of Cellular and Molecular Biology, National Institute on Aging, Baltimore, MD 21224, USA
    Mol Cell 27:842-50. 2007
    ..We propose that the intervening D(H) genes are actively suppressed by repeat-induced epigenetic silencing, which is reflected in their infrequent representation in DJ(H) junctions compared to the flanking D(H) genes...
  20. ncbi request reprint Role of NF-kappaB in the anti-inflammatory effects of tocotrienols
    Mary Kaileh
    Laboratory of Cellular and Molecular Biology, National Institute on Aging, Baltimore, MD 21224, USA
    J Am Coll Nutr 29:334S-339S. 2010
    ..Because NF-kappaB-dependent gene regulation is important in virtually all mammalian cell types, it is critical to keep in mind some basic features of its functions when considering interventional therapeutics...
  21. ncbi request reprint Genetic and epigenetic regulation of IgH gene assembly
    Ranjan Sen
    Laboratory of Cellular and Molecular Biology, National Institute on Aging National Institutes of Health, 5600 Nathan Shock Drive, Baltimore, MD 21224, USA
    Curr Opin Immunol 18:237-42. 2006
    ..Orchestration of these regulatory processes is crucial for the generation of a functional B cell repertoire...
  22. pmc Selectivity of the NF-{kappa}B response
    Ranjan Sen
    Laboratory of Cellular and Molecular Biology, National Institute on Aging, National Institutes of Health, Baltimore, Maryland 21225, USA
    Cold Spring Harb Perspect Biol 2:a000257. 2010
    ..Here, we explore the mechanistic framework in which such regulatory aspects of NF-kappaB-dependent gene expression have been analyzed because they are likely to form the basis for physiological responses...
  23. pmc Antigen-independent IFN-γ production by human naïve CD4 T cells activated by IL-12 plus IL-18
    Rachel B Munk
    Lymphocyte Cell Biology Unit, Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
    PLoS ONE 6:e18553. 2011
    ..Thus, the present study suggests that naïve CD4(+) T cells may participate in innate immunity or amplify adaptive immune responses through cytokine-induced antigen-independent cytokine production...
  24. pmc Tumor-evoked regulatory B cells promote breast cancer metastasis by converting resting CD4⁺ T cells to T-regulatory cells
    Purevdorj B Olkhanud
    Immunotherapeutics Unit, Laboratory of Immunology, National Institute on Aging, Baltimore, Maryland 21224, USA
    Cancer Res 71:3505-15. 2011
    ..Our findings have important clinical implications, as they suggest that tBregs must be controlled to interrupt the initiation of a key cancer-induced immunosuppressive event that is critical to support cancer metastasis...
  25. ncbi request reprint Regulation of immunoglobulin heavy-chain gene rearrangements
    Dipanjan Chowdhury
    Laboratory of Cellular and Molecular Biology, National Institute on Aging, Baltimore, MD 21224, USA
    Immunol Rev 200:182-96. 2004
    ..VH genes are activated subsequently and, in part, by interleukin-7. These observations lead to a model for feedback inhibition of IgH rearrangements...
  26. ncbi request reprint NF-kappaB-dependent regulation of the timing of activation-induced cell death of T lymphocytes
    Akanksha Mittal
    Rosensteil Research Center and Department of Biology, Brandeis University, Waltham, MA 02454, USA
    J Immunol 176:2183-9. 2006
    ..We propose that the timing of AICD, and thus the length of the effector phase, are regulated by transient expression of a subset of p65/RelA-dependent antiapoptotic genes...
  27. pmc Pax5 is required for recombination of transcribed, acetylated, 5' IgH V gene segments
    David G T Hesslein
    Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06520 8011, USA
    Genes Dev 17:37-42. 2003
    ..The finding of transcribed, histone acetylated gene segments that fail to recombine suggests that a Pax5-dependent regulatory mechanism is required in addition to standard constraints of accessibility to control V(H) gene recombination...
  28. ncbi request reprint Generality of the branched pathway in transcription initiation by Escherichia coli RNA polymerase
    Motoki Susa
    Structural Biology Center, National Institute of Genetics and Department of Genetics, The Graduate University for Advanced Studies, 1111 Yata, Mishima, Japan, 411 8540
    J Biol Chem 277:15407-12. 2002
    ..These findings suggest a generality of the branched pathway mechanism, which would resolve contradictory observations that have been reported for various promoters...
  29. pmc Inhibition of a transcriptional pause by RNA anchoring to RNA polymerase
    Natalia Komissarova
    Section on Microbial Genetics, Laboratory of Molecular Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 6 Center Drive, Bethesda, MD 20892 2785, USA
    Mol Cell 31:683-94. 2008
    ..We propose that RNA anchoring to the elongation complex is a widespread mechanism of pause regulation...
  30. pmc Rho-dependent transcription termination: more questions than answers
    Sharmistha Banerjee
    Laboratory of Transcription Biology, Center for DNA Fingerprinting and Diagnostics, ECIL Road, Nacharam, Hyderabad 500076, India
    J Microbiol 44:11-22. 2006
    ..An attempt has also been made to understand the physiology of Rho in the light of its phylogeny...
  31. ncbi request reprint Pentoxifylline functions as an adjuvant in vivo to enhance T cell immune responses by inhibiting activation-induced death
    Radhakrishnan Suresh
    National Institute of Immunology, Aruna Asaf Ali Road, New Delhi 110067, India
    J Immunol 169:4262-72. 2002
    ....
  32. ncbi request reprint Commitment of activated T cells to secondary responsiveness is enhanced by signals mediated by cAMP-dependent protein kinase A-I
    Monika Vig
    National Institute of Immunology, New Delhi, India
    Mol Pharmacol 62:1471-81. 2002
    ..Together, our data suggest that PKA-I-mediated signals triggered by prolonging the half-life of cAMP induced during T-cell priming increase survival of activated T cells and enhance memory T cell commitment...
  33. ncbi request reprint Naive B lymphocytes undergo homeostatic proliferation in response to B cell deficit
    Mark S Cabatingan
    Department of Molecular Genetics and Microbiology, University of Massachusetts Medical School, Worcester, MA 01655, USA
    J Immunol 169:6795-805. 2002
    ..Homeostatic B cell proliferation provides an Ag-independent mechanism for the maintenance and expansion of naive B cells selected into the mature B cell pool...
  34. ncbi request reprint Transient IL-7/IL-7R signaling provides a mechanism for feedback inhibition of immunoglobulin heavy chain gene rearrangements
    Dipanjan Chowdhury
    Department of Biology, Brandeis University, Waltham, MA 02454, USA
    Immunity 18:229-41. 2003
    ..Thus, transient signals mediate V(H) gene activation and inactivation during development...
  35. ncbi request reprint Combinatorial control of DNase I-hypersensitive site formation and erasure by immunoglobulin heavy chain enhancer-binding proteins
    Haruhiko Ishii
    Graduate Program in Biophysics and Structural Biology, Brandeis University, Waltham, Massachusetts 02454, USA
    J Biol Chem 279:7331-8. 2004
    ..We infer that chromatin constraints for transcription and nuclease sensitivity can differ...
  36. ncbi request reprint Simple fluorescence assays probing conformational changes of Escherichia coli RNA polymerase during transcription initiation
    Ranjan Sen
    Laboratory of Transcription Biology, Center for DNA Fingerprinting and Diagnosis, ECIL Road, Nacharam, Hyderabad 500076, India
    Methods Enzymol 370:598-605. 2003
  37. ncbi request reprint Using a lac repressor roadblock to analyze the E. coli transcription elongation complex
    Rodney A King
    Laboratory of Molecular Genetics, NICHD, NIH, Building 6B, Room 3B 308, Bethesda, Maryland 20892, USA
    Methods Enzymol 371:207-18. 2003
  38. ncbi request reprint Mechanisms for feedback inhibition of the immunoglobulin heavy chain locus
    Dipanjan Chowdhury
    Centre for Blood Research, Boston, MA 02115, USA
    Curr Opin Immunol 16:235-40. 2004
    ..Similar transient signals may be responsible for enforcing allelic exclusion in other V(H) gene families. D-proximal V(H) genes, however, appear to be less susceptible to feedback inhibition...
  39. ncbi request reprint A conserved zinc binding domain in the largest subunit of DNA-dependent RNA polymerase modulates intrinsic transcription termination and antitermination but does not stabilize the elongation complex
    Rodney A King
    Laboratory of Molecular Genetics, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
    J Mol Biol 342:1143-54. 2004
    ..To account for this we suggest that put RNA interacts with an additional site in the elongation complex to mediate antitermination, and that this site is occluded by the wild-type zinc binding domain...
  40. ncbi request reprint A move to exclude
    Ranjan Sen
    Nat Immunol 6:128-30. 2005
  41. ncbi request reprint Escherichia coli RNA polymerase mutations located near the upstream edge of an RNA:DNA hybrid and the beginning of the RNA-exit channel are defective for transcription antitermination by the N protein from lambdoid phage H-19B
    Anoop Cheeran
    Laboratory of Transcription Biology, Center for DNA Fingerprinting and Diagnostics, Nacharam, Hyderabad 500076, India
    J Mol Biol 352:28-43. 2005
    ..We propose that the action of N close to the active center alters the RNAP-nucleic acid interactions around the RNA:DNA hybrid, which impairs proper folding of the terminator hairpin or stabilizes the weak RNA:DNA hybrid, or both...
  42. ncbi request reprint c-Rel-dependent priming of naive T cells by inflammatory cytokines
    Daliya Banerjee
    Rosenstiel Research Center and Department of Biology, Brandeis University, Waltham, Massachusetts 02454, USA
    Immunity 23:445-58. 2005
    ..This mechanism does not operate in effector T cells where cytokine gene expression is c-Rel-independent. We propose that c-Rel plays a crucial role as a target of innate signals in T cells...
  43. pmc Mechanism of inhibition of Rho-dependent transcription termination by bacteriophage P4 protein Psu
    Bibhusita Pani
    Laboratory of Transcription Biology, Centre for DNA Fingerprinting and Diagnostics, ECIL Road, Nacharam, Hyderabad 500076, India
    J Biol Chem 281:26491-500. 2006
    ..We propose that Psu inhibits Rho-dependent termination by slowing down the translocation of Rho along the RNA because of its slow ATPase activity...
  44. pmc Transcription termination defective mutants of Rho: role of different functions of Rho in releasing RNA from the elongation complex
    Jisha Chalissery
    Laboratory of Transcription Biology, Centre for DNA Fingerprinting and Diagnostics, ECIL Road, Nacharam, Hyderabad 500076, India
    J Mol Biol 371:855-72. 2007
    ..The rate of ATP hydrolysis regulates the processivity of translocation along the RNA and is directly correlated with the efficiency of RNA release. NusG improves the speed of RNA release and is not involved in any other step...
  45. ncbi request reprint The site of action of the antiterminator protein N from the lambdoid phage H-19B
    Anoop Cheeran
    Laboratory of Transcription Biology, Centre for DNA Fingerprinting and Diagnostics, ECIL Road, Nacharam, Hyderabad 500076, India
    J Biol Chem 282:30997-1007. 2007
    ....
  46. doi request reprint Transcription termination factor rho prefers catalytically active elongation complexes for releasing RNA
    Dipak Dutta
    Laboratory of Transcription Biology, Centre for DNA Fingerprinting and Diagnostics, Nacharam, Hyderabad, India
    J Biol Chem 283:20243-51. 2008
    ....
  47. ncbi request reprint Sequence-specific interaction of nascent antiterminator RNA with the zinc-finger motif of Escherichia coli RNA polymerase
    Ranjan Sen
    Section on Microbial Genetics, Laboratory of Molecular Genetics, National Institute of Child Health and Human Development, 6B 3B308, NIH, Bethesda, MD 20892 2785, USA
    Mol Microbiol 46:215-22. 2002
    ....