Abstract:
:P450c17 is the single enzyme mediating both 17 alpha-hydroxylase (steroid 17 alpha-monooxygenase, EC 1.14.99.9) and 17,20 lyase activities in the synthesis of steroid hormones. It has been suggested that different P450c17 isozymes mediate these activities in the adrenal gland and testis. We sequenced 423 of the 509 amino acids (83%) of the porcine adrenal enzyme; based on this partial sequence, a 128-fold degenerate 17-mer was synthesized and used to screen a porcine adrenal cDNA library. This yielded a 380-base cloned cDNA, which in turn was used to isolate several human adrenal cDNAs. The longest of these, lambda hac17-2, is 1754 base pairs long and includes the full-length coding region, the complete 3'-untranslated region, and 41 bases of the 5'-untranslated region. This cDNA encodes a protein of 508 amino acids having a predicted molecular weight of 57,379.82. High-stringency screening of a human testicular cDNA library yielded a partial clone containing 1303 identical bases. RNA gel blots and nuclease S1-protection experiments confirm that the adrenal and testicular P450c17 mRNAs are indistinguishable. These data indicate that the testis possesses a P450c17 identical to that in the adrenal. The human amino acid sequence is 66.7% homologous to the corresponding regions of the porcine sequence, and the human cDNA and amino acid sequences are 80.1 and 70.3% homologous, respectively, to bovine adrenal P450c17 cDNA. Both comparisons indicate that a central region comprising amino acid residues 160-268 is hypervariable among these species of P450c17. Comparison of the amino acid sequence of P450c17 with two other human steroidogenic cytochromes P450 show much greater homology with P450c21 (28.9%), another microsomal enzyme, than with P450scc (12.3%), a mitochondrial enzyme.
journal_name
Proc Natl Acad Sci U S Aauthors
Chung BC,Picado-Leonard J,Haniu M,Bienkowski M,Hall PF,Shively JE,Miller WLdoi
10.1073/pnas.84.2.407subject
Has Abstractpub_date
1987-01-01 00:00:00pages
407-11issue
2eissn
0027-8424issn
1091-6490journal_volume
84pub_type
杂志文章abstract::The sporulation of Saccharomyces cerevisiae in the presence of [2-13C]acetate was studied by 13C NMR spectroscopy. The fate of 13C label was analyzed in vivo and in cell extracts. During the first 4 hr of sporulation the major metabolite produced from [2-13C]acetate utilization was glutamate. From the labeling pattern...
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.80.19.5847
更新日期:1983-10-01 00:00:00
abstract::Alternative splicing is critical for diversifying eukaryotic proteomes, but the rules governing and coordinating splicing events among multiple alternate splice sites within individual genes are not well understood. We developed a quantitative PCR-based strategy to quantify the expression of the 12 transcripts encoded...
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.1116712108
更新日期:2011-12-20 00:00:00
abstract::Both naturally occurring and synthetic phosphatidic acid (PtdOH) molecules show the phenomenon of spontaneous vesiculation on jump in pH value. This method involves a transient increase in pH of smectic PtdOH dispersions to values between 10 and 12. Such a pH increase induces spontaneous vesiculation with the formatio...
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.86.14.5351
更新日期:1989-07-01 00:00:00
abstract::Tumor growth requires neoangiogenesis. VEGF is the most potent proangiogenic factor. Dysregulation of hypoxia-inducible factor (HIF) or cytokine stimuli such as those involving the chemokine receptor 4/stromal-derived cell factor 1 (CXCR4/SDF-1) axis are the major cause of ectopic overexpression of VEGF in tumors. Alt...
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.1008256107
更新日期:2010-08-10 00:00:00
abstract::DNA in the macronuclei of Oxytricha fallax, as in other hypotrichous ciliate protozoa, exists as small, achromosomal molecules rather than in chromosomes. We report studies on O. fallax DNA using physicochemical procedures and nucleic acid hybridization. Macronuclear DNA molecules range in size from 22 kilobase pairs ...
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.75.10.4992
更新日期:1978-10-01 00:00:00
abstract::The mitochondrial contact site and cristae organizing system (MICOS) is a multisubunit protein complex that is essential for the proper architecture of the mitochondrial inner membrane. MICOS plays a key role in establishing and maintaining crista junctions, tubular or slit-like structures that connect the cristae 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.2009364117
更新日期:2020-08-25 00:00:00
abstract::The last 500 million years of the strontium-isotope record are shown to correlate significantly with the concurrent record of isotopic fractionation between inorganic and organic carbon after the effects of recycled sediment are removed from the strontium signal. The correlation is shown to result from the common depe...
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.022055499
更新日期:2002-04-02 00:00:00
abstract::The regulation of glycogen metabolism is critical for the maintenance of glucose and energy homeostasis in mammals. Glycogen synthase, the enzyme responsible for glycogen production, is regulated by multisite phosphorylation in yeast and mammals. We have previously identified PAS kinase as a physiological regulator 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.0508481102
更新日期:2005-11-15 00:00:00
abstract::Yawn contagion in humans has been proposed to be related to our capacity for empathy. It is presently unclear whether this capacity is uniquely human or shared with other primates, especially monkeys. Here, we show that in gelada baboons (Theropithecus gelada) yawning is contagious between individuals, especially thos...
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.0910891106
更新日期:2009-11-17 00:00:00
abstract::The four-helical bundle soluble N-ethylmaleimide-sensitive fusion protein (NSF) attachment protein receptor (SNARE) complex that mediates intracellular membrane fusion events contains a highly conserved ionic layer at the center of an otherwise hydrophobic core. This layer has an undetermined function; it consists 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.251547598
更新日期:2001-12-04 00:00:00
abstract::Extrachromosomal copies of the 1.6-kilobase transposable element Tc1 are present at the level of between 0.1 and 1.0 copy per cell in Caenorhabditis elegans strain Bergerac. Extrachromosomal elements were detected and studied using Southern hybridizations employing a Tc1-specific probe. The amount of extrachromosomal ...
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.81.13.4018
更新日期:1984-07-01 00:00:00
abstract::Eradication of an invasive species can provide significant environmental, economic, and social benefits, but eradication programs often fail. Constant and careful monitoring improves the chance of success, but an invasion may seem to be in decline even when it is expanding in abundance or spatial extent. Determining 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.1216146110
更新日期:2013-08-13 00:00:00
abstract::Positive allosteric modulation of the mu-opioid receptor (MOPr), the site of action of all clinically used opioids, represents a potential approach for the management of pain. We recently reported on positive allosteric modulators of MOPr (mu-PAMs), a class A G protein coupled receptor (GPCR). This study was designed ...
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.1415013111
更新日期:2014-12-23 00:00:00
abstract::Natural killer T (NKT) cells provide an innate-type immune response upon T cell receptor interaction with CD1d-presented antigens. We demonstrate through equilibrium tetramer binding and antigen presentation assays with Valpha14i-positive NKT cell hybridomas that the Sphingomonas glycolipid alpha-galacturonosyl cerami...
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.0600285103
更新日期:2006-03-14 00:00:00
abstract::Glyceraldehyde-3-phosphate dehydrogenase [GAPDH; D-glyceraldehyde-3-phosphate:NAD+ oxidoreductase (phosphorylating), EC 1.2.1.12] mRNA levels are induced by physiologic concentrations of insulin in cultured 3T3-F442A adipocyte and H35 hepatoma cell lines. To examine the mechanism by which insulin regulates GAPDH mRNA ...
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.85.14.5092
更新日期:1988-07-01 00:00:00
abstract::We report the discovery in Lake Cuitzeo in central Mexico of a black, carbon-rich, lacustrine layer, containing nanodiamonds, microspherules, and other unusual materials that date to the early Younger Dryas and are interpreted to result from an extraterrestrial impact. These proxies were found in a 27-m-long core as p...
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.1110614109
更新日期:2012-03-27 00:00:00
abstract::Incubation of neuroblastoma X glioma hybrid cells for 12-97 hr with methionine-enkephalin results in an increase in adenylate cyclase activity [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] that is mediated by the opiate receptor. The results show that cells become tolerant to, and dependent upon, enkephalin. ...
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.73.9.3165
更新日期:1976-09-01 00:00:00
abstract::Swainsonine, an indolizidine alkaloid, inhibits the processing of asparagine-linked glycoproteins in both cell-free extracts and animal cells in culture. Thus, in a liver particulate enzyme preparation, swainsonine at 0.1-1.0 microM inhibited the mannosidase that releases [3H]mannose from a high mannose glycopeptide 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.78.12.7393
更新日期:1981-12-01 00:00:00
abstract::Visual transduction in Drosophila is a G protein-coupled phospholipase C-mediated process that leads to depolarization via activation of the transient receptor potential (TRP) calcium channel. Inactivation-no-afterpotential D (INAD) is an adaptor protein containing PDZ domains known to interact with TRP. Immunoprecipi...
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.94.23.12682
更新日期:1997-11-11 00:00:00
abstract::The proteasome regulates cellular processes as diverse as cell cycle progression and NF-kappaB activation. In this study, we show that the potent antitumor natural product epoxomicin specifically targets the proteasome. Utilizing biotinylated-epoxomicin as a molecular probe, we demonstrate that epoxomicin covalently 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.96.18.10403
更新日期:1999-08-31 00:00:00
abstract::The bacterial pathogen Shigella flexneri causes bacillary dysentery in humans by invading coloncytes. Upon contact with epithelial cells, S. flexneri elicits localized plasma membrane projections sustained by long actin filaments which engulf the microorganism. The products necessary for Shigella entry include three 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.93.3.1254
更新日期:1996-02-06 00:00:00
abstract::Interfacial zones between tissues provide specialized, transitional junctions central to normal tissue function. Regenerative medicine strategies focused on multiple cell types and/or bi/tri-layered scaffolds do not provide continuously graded interfaces, severely limiting the integration and biological performance 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.0801988105
更新日期:2008-08-26 00:00:00
abstract::Drosophila heteroneura and D. silvestris are sympatric species living on the island of Hawaii, while D. planitibia is allopatric on the nearby island of Maui. A pronounced ethological isolation is found between the sympatric species, and none between allopatric ones, except that D. planitibia females discriminate agai...
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.71.3.901
更新日期:1974-03-01 00:00:00
abstract::IFN-alpha/beta plays an essential role in innate immunity against viral and bacterial infection. Among the proteins induced by IFN-alpha/beta are the ubiquitin-like ISG15 protein and its E1- (Ube1L) and E2- (UbcH8) conjugating enzymes, leading to the conjugation of ISG15 to cellular proteins. It is likely that ISG15 c...
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.0504754102
更新日期:2005-07-19 00:00:00
abstract::Previous studies have identified lipid-poor high density lipoproteins with electrophoretic pre-beta mobility as the initial acceptors of cell-derived cholesterol in human plasma. These lipoproteins contain apolipoprotein A-I (apo A-I) as their sole apolipoprotein. In the present study, incubation of human plasma 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.91.5.1834
更新日期:1994-03-01 00:00:00
abstract::The nit-2 major nitrogen regulatory gene of Neurospora crassa turns on the expression of various unlinked structural genes that specify nitrogen-catabolic enzymes under nitrogen-limitation conditions. The nit-2 gene encodes a protein of 1036 amino acid residues with a single zinc finger and a downstream basic region 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.87.14.5331
更新日期:1990-07-01 00:00:00
abstract::Maintaining active growth and effective immune responses is often costly for a living organism to survive. Fine-tuning the shared cross-regulators is crucial for metazoans and plants to make a trade-off between growth and immunity. The Arabidopsis regulatory receptor-like kinase BAK1 complexes with the receptor kinase...
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.1302154110
更新日期:2013-07-16 00:00:00
abstract::SapB is a morphogenetic peptide that is important for aerial mycelium formation by the filamentous bacterium Streptomyces coelicolor. Production of SapB commences during aerial mycelium formation and depends on most of the genes known to be required for the morphogenesis of aerial hyphae. Furthermore, the application ...
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.0404220101
更新日期:2004-08-03 00:00:00
abstract::Far-red radiation (FR) reflected by green tissues is a key signal that plants use to detect the proximity of future competitors. Perception of increased levels of FR elicits a suite of responses collectively known as the shade-avoidance syndrome, which includes increased stem elongation, production of erect leaves, an...
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.0509805103
更新日期:2006-05-02 00:00:00
abstract::In early stages of various pulmonary diseases, such as emphysema and fibrosis, the change in X-ray attenuation is not detectable with absorption-based radiography. To monitor the morphological changes that the alveoli network undergoes in the progression of these diseases, we propose using the dark-field signal, which...
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.1206684109
更新日期:2012-10-30 00:00:00