Abstract:
:Cyclic electron flow (CEF) around photosystem I is thought to balance the ATP/NADPH energy budget of photosynthesis, requiring that its rate be finely regulated. The mechanisms of this regulation are not well understood. We observed that mutants that exhibited constitutively high rates of CEF also showed elevated production of H2O2. We thus tested the hypothesis that CEF can be activated by H2O2 in vivo. CEF was strongly increased by H2O2 both by infiltration or in situ production by chloroplast-localized glycolate oxidase, implying that H2O2 can activate CEF either directly by redox modulation of key enzymes, or indirectly by affecting other photosynthetic processes. CEF appeared with a half time of about 20 min after exposure to H2O2, suggesting activation of previously expressed CEF-related machinery. H2O2-dependent CEF was not sensitive to antimycin A or loss of PGR5, indicating that increased CEF probably does not involve the PGR5-PGRL1 associated pathway. In contrast, the rise in CEF was not observed in a mutant deficient in the chloroplast NADPH:PQ reductase (NDH), supporting the involvement of this complex in CEF activated by H2O2. We propose that H2O2 is a missing link between environmental stress, metabolism, and redox regulation of CEF in higher plants.
journal_name
Proc Natl Acad Sci U S Aauthors
Strand DD,Livingston AK,Satoh-Cruz M,Froehlich JE,Maurino VG,Kramer DMdoi
10.1073/pnas.1418223112subject
Has Abstractpub_date
2015-04-28 00:00:00pages
5539-44issue
17eissn
0027-8424issn
1091-6490pii
1418223112journal_volume
112pub_type
杂志文章abstract::The activity of a number of proteins is regulated by self-processing reactions. Elegant examples are the cleavage of the prokaryotic LexA and lambdaCI transcriptional repressors and the UmuD-like mutagenesis proteins. Various studies support the hypothesis that LexA and lambdaCI cleavage reactions are predominantly in...
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.95.4.1478
更新日期:1998-02-17 00:00:00
abstract::Gene amplification may be visualized within a chromosome as a homogeneously stained region (HSR) and HSRs have rarely been reported in human tumor cells with identification of the amplified gene. A parental line and seven clones derived from KB cells resistant to methotrexate (MTX) contain dihydrofolate reductase (DHF...
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.80.3.807
更新日期:1983-02-01 00:00:00
abstract::The Golgi apparatus is a membrane-bounded organelle with the characteristic shape of a series of stacked flat cisternae. During mitosis in mammalian cells, the Golgi apparatus is once fragmented into small vesicles and then reassembled to form the characteristic shape again in each daughter cell. The mechanism and det...
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.1619264114
更新日期:2017-05-16 00:00:00
abstract::Two molecular forms of pyrophosphate-dependent phosphofructokinase (PP(i)-PFK; pyrophosphate:D-fructose-6-phosphate 1-phosphotransferase; EC 2.7.1.90) have been found whose activity depends upon association and dissociation characteristics regulated by fructose 2,6-bisphosphate (Fru-2,6-P(2)). PP(i)-PFK was purified 2...
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.81.16.5051
更新日期:1984-08-01 00:00:00
abstract::The succession from aerobic and facultative anaerobic bacteria to obligate anaerobes in the infant gut along with the differences between the compositions of the mucosally adherent vs. luminal microbiota suggests that the gut microbes consume oxygen, which diffuses into the lumen from the intestinal tissue, maintainin...
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.1718635115
更新日期:2018-04-17 00:00:00
abstract::E2F is a heterodimeric transcription factor that regulates the expression of genes at the G1/S boundary and is composed of two related but distinct families of proteins, E2F and DP. E2F/DP heterodimers form complexes with the retinoblastoma (Rb) protein, the Rb-related proteins p107 and p130, and cyclins/cdks in a cel...
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.93.15.7594
更新日期:1996-07-23 00:00:00
abstract::Interleukin 2 (IL-2)-deficient (IL-2-/-) mice develop hemolytic anemia and chronic inflammatory bowel disease. Importantly, the induction of disease in IL-2-deficient mice is critically dependent on CD4+ T cells. We have studied the requirements of T cells from IL-2-deficient mice for costimulation with B7 antigens. 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.93.7.2903
更新日期:1996-04-02 00:00:00
abstract::Many changes have been described in the brains of Alzheimer's disease (AD) patients, including loss of neurons and formation of senile plaques and neurofibrillary tangles. The molecular mechanisms underlying these pathologies are unclear. Northern blot, dot-blot, and reverse transcription-coupled PCR analyses have dem...
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.95.16.9620
更新日期:1998-08-04 00:00:00
abstract::We report here studies of tryptophan (Trp) solvation dynamics in water and in the Pyrococcus furiosus rubredoxin protein, including the native and its apo and denatured forms. We also report results on energy transfer from Trp to the iron-sulfur [Fe-S] cluster. Trp fluorescence decay with the onset of solvation dynami...
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.012582399
更新日期:2002-01-08 00:00:00
abstract::Excited states of proteins may play important roles in function, yet are difficult to study spectroscopically because of their sparse population. High hydrostatic pressure increases the equilibrium population of excited states, enabling their characterization [Akasaka K (2003) Biochemistry 42:10875-85]. High-pressure ...
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.1320124110
更新日期:2013-12-03 00:00:00
abstract::After exposure to low density lipoprotein (LDL) that had been minimally modified by oxidation (MM-LDL), human endothelial cells (EC) and smooth muscle cells (SMC) cultured separately or together produced 2- to 3-fold more monocyte chemotactic activity than did control cells or cells exposed to freshly isolated LDL. 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.87.13.5134
更新日期:1990-07-01 00:00:00
abstract::Bones of the flightless sea duck (Chendytes lawi) from 14 archaeological sites along the California coast indicate that humans hunted the species for at least 8,000 years before it was driven to extinction. Direct (14)C dates on Chendytes bones show that the duck was exploited on the southern California islands as ear...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 历史文章,杂志文章
doi:10.1073/pnas.0711140105
更新日期:2008-03-18 00:00:00
abstract::The NIFA protein of Klebsiella pneumoniae is required for transcription of all nif (nitrogen fixation) operons except the regulatory nifLA operon itself. NIFA activates transcription of nif operons by the alternative holoenzyme form of RNA polymerase, sigma 54-holoenzyme, in a nucleoside triphosphate (NTP)-dependent m...
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.91.1.103
更新日期:1994-01-04 00:00:00
abstract::Coral bleaching, caused by heat stress, is accompanied by the light-induced loss of photosynthetic pigments in in situ symbiotic dinoflagellate algae (Symbiodinium spp.). However, the molecular mechanisms responsible for pigment loss are poorly understood. Here, we show that moderate heat stress causes photobleaching ...
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.0708554105
更新日期:2008-03-18 00:00:00
abstract::The synthesis of antiviral beta-chemokines has joined cytolysis as a potential mechanism for the control of HIV-1 infection by CD8(+) T cells. Recent evidence suggests that these two effector functions can diverge in some individuals infected with HIV-1; however, little is known about the CD8(+) T cell subsets in norm...
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.161298998
更新日期:2001-07-31 00:00:00
abstract::The mitochondrial genome of Saccharomyces cerevisiae codes for 24 tRNAs. The nucleotide sequences of the tRNA genes suggest a unique set of rules that govern the decoding of the mitochondrial genetic code. The four codons of unmixed fmilies are recognized by single tRNAs that always have a U in the wobble position 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.77.6.3167
更新日期:1980-06-01 00:00:00
abstract::The pineal organ of the lizard Anolis carolinensis can be maintained for up to 10 days in superfused organ culture. During this time it synthesizes and releases melatonin into the medium flowing slowly over it. Collection of timed aliquots of medium and subsequent analysis for melatonin by radioimmunoassay reveal circ...
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.80.19.6119
更新日期:1983-10-01 00:00:00
abstract::Immunoreactive and bioreactive corticotropin (ACTH-like) activities have been detected in the median eminence and remaining medial basal hypothalamus of both normal and hypophysectomized adult male rats: bioreactive ACTH (pg/100 mug of protein) 1028 in median eminence and 1289 in medial basal hypothalamus; immunoreact...
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.74.2.648
更新日期:1977-02-01 00:00:00
abstract::The hallmark of the menstrual cycle is extensive steroid-dependent tissue turnover. Estrogen mediates endometrial cell growth and structural remodeling, whereas progesterone suppresses estrogen-dependent proliferation and promotes cellular differentiation. In nonfertile cycles, tissue degradation and menstruation occu...
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.91.21.10129
更新日期:1994-10-11 00:00:00
abstract::Memory CD8 T cells provide durable protection against diverse intracellular pathogens and can be broadly segregated into distinct circulating and tissue-resident populations. Paradigmatic studies have demonstrated that circulating memory cells can be further divided into effector memory (Tem) and central memory (Tcm) ...
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.2008571117
更新日期:2020-10-13 00:00:00
abstract::Staphylococcus aureus is a leading cause of both nosocomial and community-acquired infection. Biofilm formation at the site of infection reduces antimicrobial susceptibility and can lead to chronic infection. During biofilm formation, a subset of cells liberate cytoplasmic proteins and DNA, which are repurposed to for...
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.1704544114
更新日期:2017-07-18 00:00:00
abstract::Ral (Ras-like) GTPases are directly activated by oncogenic Ras GTPases. Mutant K-Ras (G12C) has enabled the development of covalent K-Ras inhibitors currently in clinical trials. However, Ral, and the overwhelming majority of mutant oncogenic K-Ras, are devoid of a druggable pocket and lack an accessible cysteine for ...
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.1913654117
更新日期:2020-03-31 00:00:00
abstract::Immunoglobulin- or multiple myeloma-associated amyloidosis has been distinguished by the tissue deposition of Congophilic, fibrillar protein consisting of light chains or light-chain fragments (AL amyloidosis). We now report the isolation and characterization of another form of immunoglobulin-associated amyloid obtain...
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.87.17.6542
更新日期:1990-09-01 00:00:00
abstract::Methylation on lysine 9 of histone H3 (H3K9me) and DNA methylation play important roles in the transcriptional silencing of specific genes and repetitive elements. Both marks are detected on class I and II endogenous retroviruses (ERVs) in murine embryonic stem cells (mESCs). Recently, we reported that the H3K9-specif...
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.1014660108
更新日期:2011-04-05 00:00:00
abstract::Cytochrome c peroxidase reacts with peroxide to form compound I, which contains an oxyferryl heme and an indolyl radical at Trp-191. The indolyl free radical has a half-life of several hours at room temperature, and this remarkable stability is essential for the catalytic function of cytochrome c peroxidase. To probe ...
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.91.23.11118
更新日期:1994-11-08 00:00:00
abstract::Aerobic glycolysis (AG), that is, the nonoxidative metabolism of glucose, contributes significantly to anabolic pathways, rapid energy generation, task-induced activity, and neuroprotection; yet high AG is also associated with pathological hallmarks such as amyloid-β deposition. An important yet unresolved question is...
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.2013232118
更新日期:2021-01-05 00:00:00
abstract::A synthetic DNA based on the known amino acid sequence of the brain/gut peptide cholecystokinin (CCK) was synthesized. This DNA contained deoxyinosines at ambiguous codon positions and was used as a probe to isolate the CCK gene directly from a human genomic library. Nucleotide sequence analysis of the isolated gene r...
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.82.7.1931
更新日期:1985-04-01 00:00:00
abstract::Soot particles produced by incomplete combustion processes are one of the major components of urban air pollution. Chemistry at their surfaces lead to the heterogeneous conversion of several key trace gases; for example NO(2) interacts with soot and is converted into HONO, which rapidly photodissociates to form OH in ...
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.0908341107
更新日期:2010-04-13 00:00:00
abstract::We utilized the presence of hepatic receptors for galactose-terminal glycoproteins to achieve specific rescue of differentiated hepatocytes from methotrexate toxicity. This was accomplished by administration of a conjugate formed by covalent coupling of the methotrexate antagonist, folinic acid (leucovorin), to galact...
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.80.10.3078
更新日期:1983-05-01 00:00:00
abstract::Theories of evolution that state natural selection acts on individuals have been modified to include multiple levels of selection. Here we demonstrate in chimeric protochordates that primitive germ cell (pgc) and somatic cell (psc) lineages have traits that also make them likely units of natural selection. Specificall...
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.96.16.9148
更新日期:1999-08-03 00:00:00