At least six forms of extremely homologous cytochromes P-450 in rat liver are encoded at two closely linked genetic loci.

abstract：:Tangier disease is a familial disorder characterized by orange tonsils, cholesterol ester deposition in reticuloendothelial cells, abnormal chylomicron remnants, and a marked reduction in high density lipoproteins. Plasma concentrations of the apolipoproteins apo-A-I and apoA-II in patients with Tangier disease are ap...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kay LL,Ronan R,Schaefer EJ,Brewer HB Jr

更新日期：1982-04-01 00:00:00

abstract：:Intrinsically disordered proteins (IDPs) are characterized by a lack of defined structure. Instead, they populate ensembles of rapidly interconverting conformations with marginal structural stabilities. Changes in solution conditions such as temperature and crowding agents consequently affect IDPs more than their fold...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Wicky BIM,Shammas SL,Clarke J

更新日期：2017-09-12 00:00:00

abstract：:A discussion of the expected mechanism of radical reduction of carbonyl compounds by dihydroflavin as it relates to the structure of the carbonyl compound is provided. Factors which must be taken into account are the free energies of formation of the radical anions (CR2O), THE ACIDITY OF THE CONJUGATE ACID OF THE CARB...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Williams RF,Shinkai S,Bruice TC

更新日期：1975-05-01 00:00:00

abstract：:Liver fibrosis interferes with normal liver function and facilitates hepatocellular carcinoma (HCC) development, representing a major threat to human health. Here, we present a comprehensive perspective of microRNA (miRNA) function on targeting the fibrotic microenvironment. Starting from a murine HCC model, we identi...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Winkler I,Bitter C,Winkler S,Weichenhan D,Thavamani A,Hengstler JG,Borkham-Kamphorst E,Kohlbacher O,Plass C,Geffers R,Weiskirchen R,Nordheim A

更新日期：2020-01-07 00:00:00

abstract：:A 3- to 5-year cycle of vole abundances is a characteristic phenomenon in the ecology of northern regions, and their explanation stands as a central theoretical challenge in population ecology. Although many species of voles usually coexist and are in severe competition for food and breeding space, the role of intersp...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Hansen TF,Stenseth NC,Henttonen H,Tast J

更新日期：1999-02-02 00:00:00

abstract：:Tumor-derived adhesion factor (TAF) was previously identified as a cell adhesion molecule secreted by human bladder carcinoma cell line EJ-1. To elucidate the physiological function of TAF, we examined its distribution in human normal and tumor tissues. Immunochemical staining with an anti-TAF monoclonal antibody show...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Akaogi K,Okabe Y,Sato J,Nagashima Y,Yasumitsu H,Sugahara K,Miyazaki K

更新日期：1996-08-06 00:00:00

abstract：:In the process of molecularly cloning unintegrated proviral DNA from NIH-3T3 mouse cells infected with Rauscher murine leukemia virus, we observed the occurrence of clones with inserts smaller than the expected Rauscher murine leukemia virus fragments. The insert of one of these clones, lambda.Xe-1, was characterized ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： van der Hoorn FA,Onnekink C,van der Putten H,Zijlstra M,Bloemers HP

更新日期：1982-03-01 00:00:00

abstract：:The inhibitory protein that binds calmodulin and thus prevents activation of several Ca2+-dependent enzymes by calmodulin is shown to also bind four Ca2+ per mol of protein with high affinity (Kd less than or equal to 10(-6) M). On the basis of its Ca2+- binding properties and its localization to nervous tissue, the i...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Klee CB,Crouch TH,Krinks MH

更新日期：1979-12-01 00:00:00

abstract：:Vibrio cholerae is both an inhabitant of estuarine environments and the etiologic agent of the diarrheal disease cholera. Previous work has demonstrated that V. cholerae forms both an exopolysaccharide-dependent biofilm and a Ca2+-dependent biofilm. In this work, we demonstrate a role for the O-antigen polysaccharide ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kierek K,Watnick PI

更新日期：2003-11-25 00:00:00

abstract：:We have employed Xenopus embryos to express human acetylcholinesterase (AcChoEase; EC 3.1.1.7) in developing synapses. Transcription of AcChoEase mRNA was driven by a 2.2-kb sequence upstream from the initiator AUG in the ACHE gene encoding AcChoEase, with multiple potential sites for binding universal and tissue-spec...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Ben Aziz-Aloya R,Seidman S,Timberg R,Sternfeld M,Zakut H,Soreq H

更新日期：1993-03-15 00:00:00

abstract：:Recently, tRNA aminoacyl-tRNA synthetase pairs have been evolved that allow one to genetically encode a large array of unnatural amino acids in both prokaryotic and eukaryotic organisms. We have determined the crystal structures of two substrate-bound Methanococcus jannaschii tyrosyl aminoacyl-tRNA synthetases that ch...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Turner JM,Graziano J,Spraggon G,Schultz PG

更新日期：2006-04-25 00:00:00

abstract：:A detailed conformational analysis of the known crystal structures of vitamin A, carotenoid, and xanthenoid derivatives has been made. These studies suggest that the visual chromophore 11-cis retinal and its isomers may each occur in several different conformational states, which would be expected to have different li...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Sundaralingam M,Beddell C

更新日期：1972-06-01 00:00:00

abstract：:I describe the self-splicing of an RNA that consists of exon sequences flanked by group II intron sequences. I find that this RNA undergoes accurate splicing in vitro, yielding an excised exon circle. This splicing reaction involves the joining of the 5' splice site at the end of an exon to the 3' splice site at the b...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Jarrell KA

更新日期：1993-09-15 00:00:00

abstract：:We have synthesized 175-nucleotide-long probes for the DNA of human histocompatibility antigens HLA-DR alpha and beta by extending on poly(A)+ mRNA from B-cell lines with short synthetic deoxyribonucleotide primers complementary to the predicted nucleotide sequence of the NH2 terminus of both polypeptides. The synthes...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Das HK,Biro PA,Cohen SN,Erlich HA,von Gabain A,Lawrance SK,Lemaux PG,McDevitt HO,Peterlin BM,Schulz MF,Sood AK,Weissman SM

更新日期：1983-03-01 00:00:00

abstract：:Prions are thought to consist mainly or entirely of misfolded PrP, a constitutively expressed host protein. Prions associated with the same PrP sequence may occur in the form of different strains; the strain phenotype is believed to be encoded by the conformation of the PrP. Some cell lines can be persistently infecte...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Mahal SP,Baker CA,Demczyk CA,Smith EW,Julius C,Weissmann C

更新日期：2007-12-26 00:00:00

abstract：:Mitochondrial cytochrome c oxidase plays an essential role in aerobic cellular respiration, reducing dioxygen to water in a process coupled with the pumping of protons across the mitochondrial inner membrane. An aspartate residue, Asp-51, located near the enzyme surface, undergoes a redox-coupled x-ray structural chan...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Tsukihara T,Shimokata K,Katayama Y,Shimada H,Muramoto K,Aoyama H,Mochizuki M,Shinzawa-Itoh K,Yamashita E,Yao M,Ishimura Y,Yoshikawa S

更新日期：2003-12-23 00:00:00

abstract：:The potent transforming activity of membrane-targeted Raf-1 (Raf-CAAX) suggests that Ras transformation is triggered primarily by a Ras-mediated translocation of Raf-1 to the plasma membrane. However, whereas constitutively activated mutants of Ras [H-Ras(61L) and K-Ras4B(12V)] and Raf-1 (DeltaRaf-22W and Raf-CAAX) ca...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Oldham SM,Clark GJ,Gangarosa LM,Coffey RJ Jr,Der CJ

更新日期：1996-07-09 00:00:00

abstract：:A synthetic 67-nt RNA substrate, containing a 32P-labeled cap-1 structure (m7G32pppGm) was specifically cleaved by the influenza virus RNA polymerase (EC 2.7.7.48) to yield a single capped 11-nt fragment capable of directly priming transcription. An analysis of systematic truncations of this RNA substrate demonstrated...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Chung TD,Cianci C,Hagen M,Terry B,Matthews JT,Krystal M,Colonno RJ

更新日期：1994-03-15 00:00:00

abstract：:Perfusion of rat hearts with Krebs--Henseleit medium containing 10 mM L-leucine methyl ester leads to swelling of lysosomes and loss of lysosomal integrity within 30-60 min. No morphological changes can be detected in the nuclei, mitochondria, sarcoplasmic reticulum, or Golgi complex as a result of the treatment with ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Reeves JP,Decker RS,Crie JS,Wildenthal K

更新日期：1981-07-01 00:00:00

abstract：:Ubiquitin is a highly conserved protein that is encoded by a multigene family. It is generally believed that this gene family is subject to concerted evolution, which homogenizes the member genes of the family. However, protein homogeneity can be attained also by strong purifying selection. We therefore studied the pr...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Nei M,Rogozin IB,Piontkivska H

更新日期：2000-09-26 00:00:00

abstract：:Free hydrogen (H2) is a basal energy source underlying chemosynthetic activity within igneous ocean crust. In an attempt to systematically account for all H2 within young oceanic lithosphere (<10 Ma) near the Mid-Ocean Ridge (MOR), we construct a box model of this environment. Within this control volume, we assess abi...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Worman SL,Pratson LF,Karson JA,Schlesinger WH

更新日期：2020-06-16 00:00:00

abstract：:The multisubunit enzyme aspartate transcarbamylase consists of six copies of two types of polypeptide chains, catalytic (C) and regulatory (R). A complex formed by the partial dissociation of this enzyme has been isolated. This species, which has the structure C(6)R(4), is a likely intermediate in the stepwise dissoci...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Evans DR,Pastra-Landis SC,Lipscomb WN

更新日期：1974-04-01 00:00:00

abstract：:The kinetics of the reduction of horseheart ferricytochrome c by sodium dithionite (phosphate buffer-sodium chloride; pH 6.5, mu = 1.0, 25 degrees ) features two reaction pathways; one with the rate constant k(3) = 1.17 x 10(4) M(-1) sec(-1), the other with the rate constant k(1)k(2)/k(-1) = 6.0 x 10(4) M(-1) sec(-1)....

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Creutz C,Sutin N

更新日期：1973-06-01 00:00:00

abstract：:The auditory cortex is critical for perceiving a sound's location. However, there is no topographic representation of acoustic space, and individual auditory cortical neurons are often broadly tuned to stimulus location. It thus remains unclear how acoustic space is represented in the mammalian cerebral cortex and how...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Miller LM,Recanzone GH

更新日期：2009-04-07 00:00:00

abstract：:Neurological dysfunction caused by traumatic brain injury results in profound changes in net synaptic efficacy, leading to impaired cognition. Because excitability is directly controlled by the balance of excitatory and inhibitory activity, underlying mechanisms causing these changes were investigated using lateral fl...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Cole JT,Mitala CM,Kundu S,Verma A,Elkind JA,Nissim I,Cohen AS

更新日期：2010-01-05 00:00:00

abstract：:Antagonists of growth hormone-releasing hormone (GH-RH) inhibit the growth of various tumors through mechanisms that involve the suppression of the insulin-like growth factor I and/or insulin-like growth factor II levels or secretion. In the present study, we tested the hypothesis that the tumor inhibition is associat...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kiaris H,Schally AV

更新日期：1999-01-05 00:00:00

abstract：:F1-ATPase, the catalytic domain of ATP synthase, synthesizes most of the ATP in living organisms. Running in reverse powered by ATP hydrolysis, this hexameric ring-shaped molecular motor formed by three αβ-dimers creates torque on its central γ-subunit. This reverse operation enables detailed explorations of the mecha...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Okazaki K,Hummer G

更新日期：2013-10-08 00:00:00

abstract：:Dimerization of human immunodeficiency virus type 1 protease (HIV-1 PR) monomers is an essential prerequisite for viral proteolytic activity and the subsequent generation of infectious virus particles. Disruption of the dimer interface inhibits this activity as does formation of heterodimers between wild-type and defe...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： McPhee F,Good AC,Kuntz ID,Craik CS

更新日期：1996-10-15 00:00:00

abstract：:Cranial neural crest cells (crNCCs) migrate from the neural tube to the pharyngeal arches (PAs) of the developing embryo and, subsequently, differentiate into bone and connective tissue to form the mandible. Within the PAs, crNCCs respond to local signaling cues to partition into the proximo-distally oriented subdomai...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Vincentz JW,Casasnovas JJ,Barnes RM,Que J,Clouthier DE,Wang J,Firulli AB

更新日期：2016-07-05 00:00:00

abstract：:A segment of DNA containing cya, the gene for adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1], has been isolated from Salmonella typhimurium. The phage lambda gt4 was used as a cloning vector and adenylate cyclase-positive hybrid phages were isolated that complemented adenylate cyclase-negative bac...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Wang JY,Clegg DO,Koshland DE Jr

更新日期：1981-08-01 00:00:00