Abstract:
:Levels and subcellular distribution of connexin 43 (Cx43), a gap junction protein, were studied in hamster leukocytes before and after activation with endotoxin (lipopolysaccharide, LPS) both in vitro and in vivo. Untreated leukocytes did not express Cx43. However, Cx43 was clearly detectable by indirect immunofluorescence in cells treated in vitro with LPS (1 micrograms/ml, 3 hr). Cx43 was also detected in leukocytes obtained from the peritoneal cavity 5-7 days after LPS-induced inflammation. In some leukocytes that formed clusters Cx43 immunoreactivity was present at appositional membranes, suggesting formation of homotypic gap junctions. In cell homogenates of activated peritoneal macrophages, Cx43, detected by Western blot analysis, was mostly unphosphorylated. A second in vivo inflammatory condition studied was that induced by ischemia-reperfusion of the hamster cheek pouch. In this system, leukocytes that adhered to venular endothelial cells after 1 hr of ischemia, followed by 1 hr of reperfusion, expressed Cx43. Electron microscope observations revealed small close appositions, putative gap junctions, at leukocyte-endothelial cell and leukocyte-leukocyte contacts. These results indicate that the expression of Cx43 can be induced in leukocytes during an inflammatory response which might allow for heterotypic or homotypic intercellular gap junctional communication. Gap junctions may play a role in leukocyte extravasation.
journal_name
Proc Natl Acad Sci U S Aauthors
Jara PI,Boric MP,Sáez JCdoi
10.1073/pnas.92.15.7011subject
Has Abstractpub_date
1995-07-18 00:00:00pages
7011-5issue
15eissn
0027-8424issn
1091-6490journal_volume
92pub_type
杂志文章abstract::Chromosome-specific gene regulation is known thus far only as a mechanism to equalize the transcriptional activity of the single male X chromosome with that of the two female X chromosomes. In Drosophila melanogaster, a complex including the five Male-Specific Lethal (MSL) proteins, "paints" the male X chromosome, med...
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.111581298
更新日期:2001-05-22 00:00:00
abstract::The levels of c-myc, c-fos, and JE mRNAs accumulate in a biphasic pattern following infection of quiescent BALB/c 3T3 mouse cells with polyomavirus. Maximal levels of c-myc and c-fos mRNAs were seen within 1 hr and were nearly undetectable at 6 hr after infection. At 12 hr after infection mRNA levels were again maxima...
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.84.5.1210
更新日期:1987-03-01 00:00:00
abstract::A high molecular weight protein (HMWP) with properties similar to those of both actin-binding protein (ABP) and filamin has been isolated from cultured baby hamster kidney (BHK-21) cells. The protein was present in an actomyosin-depleted sucrose extract of the cells and was eluted, upon gel chromatography on Sepharose...
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.76.9.4484
更新日期:1979-09-01 00:00:00
abstract::An unusual system of genetic exchange exists in the purple nonsulfur bacterium Rhodobacter capsulatus. DNA transmission is mediated by a small bacteriophage-like particle called the gene transfer agent (GTA) that transfers random 4.5-kb segments of the producing cell's genome to recipient cells, where allelic replacem...
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.97.2.859
更新日期:2000-01-18 00:00:00
abstract::By optically probing with a focused, low-power laser beam, we measured the spontaneous deflection fluctuations of the sensory hair bundles on frog saccular hair cells with a sensitivity of about 1 pm/square root of Hz. The preparation was illuminated by two orthogonally polarized laser beams separated by only about 0....
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.86.14.5371
更新日期:1989-07-01 00:00:00
abstract::H-2(q) mice (DBA/1) do not make an antibody response to a synthetic aminoacid polymer, (Glu, Ala,Tyr(10)), after an immunizing regimen that produces a good antibody response in mouse strains with other H-2 alleles. Their thymocytes, however, show evidence of recognizing this antigen since they synthesize DNA when they...
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.70.1.250
更新日期:1973-01-01 00:00:00
abstract::Influenza viruses contain segmented, negative-strand RNA genomes. Genome segmentation facilitates reassortment between different influenza virus strains infecting the same cell. This phenomenon results in the rapid exchange of RNA segments. In this study, we have developed a method to prevent the free reassortment 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.0908897106
更新日期:2009-09-15 00:00:00
abstract::Ras proteins are small GTP binding proteins that serve as critical relays in a variety of signal transduction pathways in eukaryotic cells. Like most metazoan Ras proteins, yeast Ras is post-translationally modified by addition of a farnesyl and a palmitoyl moiety, and these modifications are required for targeting th...
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.92.7.2984
更新日期:1995-03-28 00:00:00
abstract::The DNA damage response is an essential process for the survival of living cells. In a subset of stress-responsive genes in humans, Elongin controls transcription in response to multiple stimuli, such as DNA damage, oxidative stress, and heat shock. Yeast Elongin (Ela1-Elc1), along with Def1, is known to facilitate ub...
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.1707955114
更新日期:2017-12-12 00:00:00
abstract::The long QT syndrome (LQTS) is a heritable disorder that predisposes to sudden cardiac death. LQTS is caused by mutations in ion channel genes including HERG and KCNE1, but the precise mechanisms remain unclear. To clarify this situation we injected adenoviral vectors expressing wild-type or LQT mutants of HERG and KC...
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.091239098
更新日期:2001-04-24 00:00:00
abstract::In 1999, the population of Vancouver Island, Canada, began to experience an outbreak of a fatal fungal disease caused by a highly virulent lineage of Cryptococcus gattii. This organism has recently spread to the Canadian mainland and Pacific Northwest, but the molecular cause of the outbreak remains unknown. Here we s...
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.0902963106
更新日期:2009-08-04 00:00:00
abstract::It has been shown that [35S]methionine is incorporated into the [Met]enkephalin sequences of a 22,000-dalton enkephalin-containing protein in the adrenal medulla. Pulse-chase experiments indicate that label is incorporated into the large polypeptide before it appears in free [Met]enkephalin and a smaller [Met]enkephal...
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.77.11.6889
更新日期:1980-11-01 00:00:00
abstract::Measles still remains a major cause of childhood morbidity and mortality worldwide. Measles virus (MV) vaccines are highly successful, but the mechanism underlying their efficacy has been unclear. Here we report the crystal structure of the MV attachment protein, hemagglutinin, responsible for MV entry. The receptor-b...
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.0707830104
更新日期:2007-12-04 00:00:00
abstract::Previous studies have identified an ATP-dependent DNA helicase activity intrinsic to the human minichromosome maintenance (MCM) complex, composed of MCM subunits 4, 6, and 7 [Ishimi, Y. (1997) J. Biol. Chem. 272, 24508-24513]. In contrast to the presence of multiple MCM genes (at least six) in eukaryotes, the archaeon...
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.96.26.14783
更新日期:1999-12-21 00:00:00
abstract::Hybridomas producing human monoclonal IgM antibodies (mAbs) against bacterial lipopolysaccharide (LPS) were generated by fusion of B lymphocytes from sensitized human spleen with heteromyeloma cells. The splenocytes were from patients undergoing splenectomy during staging for Hodgkin disease after vaccination with 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.82.6.1790
更新日期:1985-03-01 00:00:00
abstract::Outer membrane protein (OMP) biogenesis is critical to bacterial physiology because the cellular envelope is vital to bacterial pathogenesis and antibiotic resistance. The process of OMP biogenesis has been studied in vivo, and each of its components has been studied in isolation in vitro. This work integrates paramet...
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.1601002113
更新日期:2016-08-16 00:00:00
abstract::To investigate the properties of metazoan replication origins, recent studies in cell culture have adopted the strategy of identifying origins using genome-wide approaches and assessing correlations with such features as transcription and histone modifications. Drosophila amplicon in follicle cells (DAFCs), genomic re...
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.1114209108
更新日期:2011-10-04 00:00:00
abstract::Human transcription factor IIA (TFIIA) is composed of three subunits (alpha, beta, and gamma). TFIIA interacts with the TATA-box binding protein and can overcome repression of transcription. TFIIA was found to be necessary for VP16-mediated transcriptional activation through a coactivator function. We have separated t...
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.93.13.6583
更新日期:1996-06-25 00:00:00
abstract::Recent findings intriguingly place DNA double-strand break repair proteins at chromosome ends in yeast, where they help maintain normal telomere length and structure. In the present study, an essential telomere function, the ability to cap and thereby protect chromosomes from end-to-end fusions, was assessed in repair...
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.96.26.14899
更新日期:1999-12-21 00:00:00
abstract::The bioluminescent bacterium Vibrio fischeri initiates a specific, persistent symbiosis in the light organ of the squid Euprymna scolopes. During the early stages of colonization, V. fischeri is exposed to host-derived nitric oxide (NO). Although NO can be both an antimicrobial component of innate immunity and a key s...
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.1003571107
更新日期:2010-05-04 00:00:00
abstract::A Mr 35,000 calmodulin-binding protein, which also possesses the ability to interact with a number of cytoskeletal elements, was purified from bovine synaptosomal membranes, using hydroxylapatite and phosphocellulose column chromatography. We call this protein "cytosynalin," which is derived from a combination of 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.84.7.1916
更新日期:1987-04-01 00:00:00
abstract::Neurons in the cochlear nuclei of duck embryos become responsive to tonal stimuli in an orderly spatial and temporal sequence. Cells responding to lower frequencies are recorded before those responding to higher frequencies. Auditory neurons are spatially arranged according to their characteristic frequencies, indicat...
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.70.6.1795
更新日期:1973-06-01 00:00:00
abstract::In adult skeletal muscles, 2 junctophilin isoforms (JPH1 and JPH2) tether the sarcoplasmic reticulum (SR) to transverse tubule (T-tubule) membranes, generating stable membrane contact sites known as triads. JPHs are anchored to the membrane of the SR by a C-terminal transmembrane domain (TMD) and bind the T-tubule mem...
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.1820980116
更新日期:2019-07-30 00:00:00
abstract::Maleyl bovine plasma albumin competed on an equimolar basis with malondialdehyde low density lipoprotein (LDL) in suppressing the lysosomal hydrolysis of 125I-labeled malondialdehyde LDL mediated by the scavenger receptor of human monocyte macrophages. Maleyl bovine plasma albumin, in which 94% of the amino groups wer...
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.82.9.2693
更新日期:1985-05-01 00:00:00
abstract::The effects of epinephrine (as low as 0.1 muM) on guanosine 3':5'-cyclic monophosphate (cGMP) and adenosine 3':5'-cyclic monophosphate (cAMP) in isolated fat cells were examined. Epinephrine increased both cGMP and cAMP levels, with the elevation of cAMP preceding the rise of cGMP. Maximal elevation was obtained with ...
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.75.6.2684
更新日期:1978-06-01 00:00:00
abstract::Molting or ecdysis is the most fundamentally important process in arthropod life history, because shedding of the exoskeleton is an absolute prerequisite for growth and metamorphosis. Although the hormonal mechanisms driving ecdysis in insects have been studied extensively, nothing is known about these processes in cr...
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.96.23.13103
更新日期:1999-11-09 00:00:00
abstract::In addition to their roles in desensitization and signaling of seven-membrane-spanning receptors, beta-arrestins have been more recently implicated in regulating non-seven-membrane-spanning receptor pathways. By using a yeast two-hybrid screen, we identified the inhibitor of NF-kappaB, IkappaBalpha, as a binding partn...
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.0402851101
更新日期:2004-06-08 00:00:00
abstract::A peptide containing 31 amino acids with inhibin-like activity has been synthesized by the solid-phase method. The synthetic product was shown to be homogeneous in high-performance liquid chromatography and paper electrophoresis. In the mouse pituitary incubation system, the follitropin-suppressing activity of the syn...
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.81.17.5399
更新日期:1984-09-01 00:00:00
abstract::To understand non-trivial biological functions, it is crucial to develop minimal synthetic models that capture their basic features. Here, we demonstrate a sequence-independent, reversible control of transcription and gene expression using a photosensitive nucleic acid binder (pNAB). By introducing a pNAB whose affini...
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.0904382106
更新日期:2009-07-28 00:00:00
abstract::The polycystic kidney diseases (PKDs) are a group of disorders characterized by the growth of epithelial cysts from the nephrons and collecting ducts of kidney tubules. The diseases can be inherited or can be provoked by environmental factors. To investigate the molecular basis of the abnormal cell growth associated w...
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.84.23.8394
更新日期:1987-12-01 00:00:00