Abstract:
:The switch from membrane-bound to secreted IgM is accomplished by producing alternative forms of mRNA from a single mu heavy-chain gene. This process might be controlled at any of three steps--transcription termination, RNA splicing, or RNA cleavage/poly(A) addition. To distinguish between these possibilities, we have constructed a model human mu gene and observed its expression in early- and late-stage murine B cells. In each case, expression of the model gene reflects the state of development of the host cell; i.e., more of the mRNA for membrane-bound IgM is made in early B cells and more of the secreted form is made in late B cells. Using systematic deletions and analyses of RNA products of the model gene, we implicate RNA cleavage/poly(A) addition as the governing reaction. Removal of the cleavage/poly(A) signal for secreted mu mRNA by a series of BAL-31 deletions produces not only a decrease in secreted mu mRNA but also a compensatory increase in the membrane-bound form. Further, transcripts that do not terminate to the 5' side of the membrane anchor exons are found in cells producing only secreted IgM. As defined by these deletions, we establish that the RNA cleavage signal spans at least 35 bases and speculate that it forms an RNA stemloop that may be important in 3' end formation.
journal_name
Proc Natl Acad Sci U S Aauthors
Danner D,Leder Pdoi
10.1073/pnas.82.24.8658subject
Has Abstractpub_date
1985-12-01 00:00:00pages
8658-62issue
24eissn
0027-8424issn
1091-6490journal_volume
82pub_type
杂志文章abstract::Effective gene therapy depends on the efficient transfer of therapeutic genes and their protein products to target cells. Lentiviral vectors appear promising for virus-mediated gene delivery and long-term expression in nondividing cells. The herpes simplex virus type 1 tegument protein VP22 has recently been shown to ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.97.21.11297
更新日期:2000-10-10 00:00:00
abstract::The ATM (ataxia telangiectasia mutated) protein plays a central role in sensing and responding to DNA double-strand breaks. Lymphoid cells are unique in undergoing physiologic double-strand breaks in the processes of Ig class switch recombination and T or B cell receptor V(D)J recombination, and a role for ATM in thes...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0611222104
更新日期:2007-04-10 00:00:00
abstract::Ca2+/calmodulin-dependent protein kinase enriched in cerebellar granule cells (CaM kinase Gr) is a neuronal calmodulin-dependent protein kinase whose purification and partial cloning from rat brain has been described. A combination of the polymerase chain reaction and cDNA library screening was used to determine the D...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.13.5784
更新日期:1991-07-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.63.2.289
更新日期:1969-06-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.96.2.604
更新日期:1999-01-19 00:00:00
abstract::Electrogenic sodium- and chloride-dependent gamma-aminobutyric acid (GABA) transport in crude synaptosomal membrane vesicles is partly inhibited by saturating levels of either of the substrate analogues cis-3-aminocyclohexanecarboxylic acid (ACHC) or beta-alanine. However, both of them together potently and fully inhi...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.87.7.2550
更新日期:1990-04-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1621072114
更新日期:2017-07-25 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0906070106
更新日期:2009-10-20 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.77.10.6139
更新日期:1980-10-01 00:00:00
abstract::Impaired regulatory T-cell function results in a severe chronic autoimmune disease affecting multiple organs in Scurfy mice and humans with the immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome. Previous studies have shown that T helper cells but not cytotoxic T cells are critical for the...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1313547110
更新日期:2013-11-19 00:00:00
abstract::Siphoviridae is the most abundant viral family on earth which infects bacteria as well as archaea. All known siphophages infecting gram+ Lactococcus lactis possess a baseplate at the tip of their tail involved in host recognition and attachment. Here, we report analysis of the p2 phage baseplate structure by X-ray cry...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1000232107
更新日期:2010-04-13 00:00:00
abstract::The MAK16 gene was first defined as a gene whose mutation resulted in loss of M1 double-stranded RNA virus-like particles. The mak16-1 mutation also produces temperature-sensitive cell growth. We report here that mak16-1 cells arrest at the nonpermissive temperature in G1 phase, such that they are mating competent. We...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.85.16.6007
更新日期:1988-08-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.81.9.2890
更新日期:1984-05-01 00:00:00
abstract::Metallic nanoscale structures are capable of supporting surface plasmon polaritons (SPPs), propagating collective electron oscillations with tight spatial confinement at the metal surface. SPPs represent one of the most promising structures to beat the diffraction limit imposed by conventional dielectric optics. Ag na...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0902064106
更新日期:2009-12-15 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0712329105
更新日期:2008-03-04 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0803834105
更新日期:2008-09-16 00:00:00
abstract::Many newly synthesized proteins have to become unfolded during translocation across biological membranes. We have analyzed the effects of various stabilization/destabilization mutations in the Ig-like module of the muscle protein titin upon its import from the N terminus or C terminus into mitochondria. The effects of...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0504495102
更新日期:2005-12-13 00:00:00
abstract::Syncytins are envelope genes of retroviral origin that have been co-opted for a role in placentation and likely contribute to the remarkable diversity of placental structures. Independent capture events have been identified in primates, rodents, lagomorphs, and carnivores, where they are involved in the formation of a...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1215787110
更新日期:2013-02-26 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2007-05-29 00:00:00
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更新日期:2012-02-07 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0805036105
更新日期:2008-07-29 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2006-03-28 00:00:00
abstract::Sympatric speciation (SS), i.e., speciation within a freely breeding population or in contiguous populations, was first proposed by Darwin [Darwin C (1859) On the Origins of Species by Means of Natural Selection] and is still controversial despite theoretical support [Gavrilets S (2004) Fitness Landscapes and the Orig...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1514896112
更新日期:2015-09-22 00:00:00
abstract::More than half of all Salmonella enterica serovar Typhi genes still remain unannotated. Although pathogenesis of S. Typhi is incompletely understood, treatment of typhoid fever is complicated by the emergence of drug resistance. Effectiveness of the currently available vaccines is also limited. In search of novel viru...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2011-02-22 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.2007151117
更新日期:2020-08-11 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1220161110
更新日期:2013-04-09 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.82.2.421
更新日期:1985-01-01 00:00:00
abstract::Uniparentally inherited mutations to antibiotic resistance and dependence in Chlamydomonas reinhardi exhibit an altered chloroplast ribosome phenotype. Genetic studies demonstrate an absolute correlation between the drug resistance or dependence and the ribosome phenotype in two such mutants. ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.67.2.1026
更新日期:1970-10-01 00:00:00
abstract::Restricted fetal growth is associated with postnatal mortality and morbidity and may be directly related to alterations in the capacity of the placenta to supply nutrients. We proposed previously that imprinted genes can regulate nutrient supply by the placenta. Here, we tested the hypothesis that the insulin-like gro...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0402508101
更新日期:2004-05-25 00:00:00