Abstract:
:The evolution of cadherins, which are essential for metazoan multicellularity and restricted to metazoans and their closest relatives, has special relevance for understanding metazoan origins. To reconstruct the ancestry and evolution of cadherin gene families, we analyzed the genomes of the choanoflagellate Salpingoeca rosetta, the unicellular outgroup of choanoflagellates and metazoans Capsaspora owczarzaki, and a draft genome assembly from the homoscleromorph sponge Oscarella carmela. Our finding of a cadherin gene in C. owczarzaki reveals that cadherins predate the divergence of the C. owczarzaki, choanoflagellate, and metazoan lineages. Data from these analyses also suggest that the last common ancestor of metazoans and choanoflagellates contained representatives of at least three cadherin families, lefftyrin, coherin, and hedgling. Additionally, we find that an O. carmela classical cadherin has predicted structural features that, in bilaterian classical cadherins, facilitate binding to the cytoplasmic protein β-catenin and, thereby, promote cadherin-mediated cell adhesion. In contrast with premetazoan cadherin families (i.e., those conserved between choanoflagellates and metazoans), the later appearance of classical cadherins coincides with metazoan origins.
journal_name
Proc Natl Acad Sci U S Aauthors
Nichols SA,Roberts BW,Richter DJ,Fairclough SR,King Ndoi
10.1073/pnas.1120685109subject
Has Abstractpub_date
2012-08-07 00:00:00pages
13046-51issue
32eissn
0027-8424issn
1091-6490pii
1120685109journal_volume
109pub_type
杂志文章abstract::The mitochondrial DNA polymerase from Drosophila embryos lacks dNTP turnover activity. However, a potent 3'----5' exonuclease activity can be detected by a specific assay in which the exonuclease excises mispaired nucleotides at the 3' termini of primed synthetic and natural DNA templates. The excision of a mispaired ...
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.86.17.6469
更新日期:1989-09-01 00:00:00
abstract::Scientific and engineering innovation is vital for American competitiveness, quality of life, and national security. However, too few American students, especially women, pursue these fields. Although this problem has attracted enormous attention, rigorously tested interventions outside artificial laboratory settings ...
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.1613117114
更新日期:2017-06-06 00:00:00
abstract::The vegetative development of the maize shoot can be divided into juvenile and adult phases based on the types of leaves produced at different times in shoot development. Models for the regulation of phase change make explicit predictions about when the identity of these types of leaves is determined. To test these mo...
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.180301597
更新日期:2000-09-12 00:00:00
abstract::Although the occurrence of epistasis and pleiotropy is widely accepted at the molecular level, its effect on the adaptive value of fitness-related genes is rarely investigated in plants. Knowledge of these features of a gene is critical to understand the molecular basis of adaptive evolution. Here we investigate the i...
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.0708209104
更新日期:2007-10-23 00:00:00
abstract::A protein fraction from B. subtilis infected with phage SP01 (fraction LGG) stimulates the activity of RNA polymerase (EC 2.7.7.6; nucleosidetriphosphate:RNA nucleotidyltransferase) core from uninfected bacteria. Fraction LGG contains a protein (P-28, molecular weight 28,000) that is labeled after phage infection and ...
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.72.6.2366
更新日期:1975-06-01 00:00:00
abstract::A typical molecular ion mass spectrum consists of a sum of signals from species of various possible isotopic compositions. Only the monoisotopic peak (e.g., all carbons are 12C; all nitrogens are 14N, etc.) has a unique elemental composition. Every other isotope peak at approximately integer multiples of approximately...
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.95.20.11532
更新日期:1998-09-29 00:00:00
abstract::RPE65 is a protein of unknown function expressed specifically by the retinal pigment epithelium. We examined all 14 exons of this gene in 147 unrelated patients with autosomal recessive retinitis pigmentosa (RP), in 15 patients with isolate RP, and in 45 patients with Leber congenital amaurosis (LCA). Sequence anomali...
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.95.6.3088
更新日期:1998-03-17 00:00:00
abstract::This work explores the concept that differential wave function overlap between excited states can be engineered within a molecular chromophore. The aim is to control excited state wave function symmetries, so that symmetry matches or mismatches result in differential orbital overlap and define low-energy trajectories ...
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.2018521118
更新日期:2021-01-26 00:00:00
abstract::The x-ray sensitive hamster cell line xrs-6 is deficient in DNA double-strand break (DSB) repair and exhibits impaired V(D)J recombination. The molecular defect in this line is in the 80-kDa subunit of the Ku autoantigen, a protein that binds to DNA ends and recruits the DNA-dependent protein kinase to DNA. Using an I...
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.93.17.8929
更新日期:1996-08-20 00:00:00
abstract::Dense granular materials display a complicated set of flow properties, which differentiate them from ordinary fluids. Despite their ubiquity, no model has been developed that captures or predicts the complexities of granular flow, posing an obstacle in industrial and geophysical applications. Here we propose a 3D cons...
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.1219153110
更新日期:2013-04-23 00:00:00
abstract::Compartmentalization of proteins into subcellular organelles in eukaryotic cells is a fundamental mechanism of regulating complex cellular functions. Many proteins of Plasmodium falciparum merozoites involved in invasion are compartmentalized into apical organelles. We have identified a new merozoite organelle that co...
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.0709999104
更新日期:2007-12-11 00:00:00
abstract::Retinoblastoma-related (RBR) genes inhibit the cell cycle primarily by repressing adenovirus E2 promoter binding factor (E2F) transcription factors, which drive the expression of numerous genes required for DNA synthesis and cell cycle progression. The RBR-E2F pathway is conserved in plants, but cereals such as maize ...
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.0813329106
更新日期:2009-03-10 00:00:00
abstract::In a previous study, we found that human neural stem cells (HNSCs) exposed to high concentrations of secreted amyloid-precursor protein (sAPP) in vitro differentiated into mainly astrocytes, suggesting that pathological alterations in APP processing during neurodegenerative conditions such as Alzheimer's disease (AD) ...
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.0705346104
更新日期:2007-07-24 00:00:00
abstract::The androgen receptor (AR) binds to androgen response elements and regulates target genes via a mechanism involving coregulators. Here we demonstrate that the AR can interact with the testicular orphan receptor-4 (TR4) and function as a repressor to down-regulate the TR4 target genes by preventing the TR4 binding to i...
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.96.26.14724
更新日期:1999-12-21 00:00:00
abstract::Xenogeneic monoclonal antibodies were prepared to the murine interleukin 2 (IL-2)-dependent HT2 cell line. One rat IgM monoclonal antibody (7D4) was identified that inhibited proliferation of the HT2 cells and of IL-2-dependent CTLL cells in the presence of crude rat IL-2 as well as of purified human IL-2. The level o...
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.80.18.5694
更新日期:1983-09-01 00:00:00
abstract::Therapeutic cancer vaccines can be effective for treating patients, but clinical responses vary considerably from patient to patient. Early indicators of a favorable response are crucial for making individualized treatment decisions and advancing vaccine design, but no validated biomarkers are currently available. In ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1073/pnas.1314722111
更新日期:2014-04-29 00:00:00
abstract::The sophistication of the insect olfactory system is elegantly demonstrated by the reception of sex pheromone by the Japanese beetle. In this insect, two olfactory receptor neurons housed in antennal sensilla placodea are highly sensitive. One neuron specifically detects the sex pheromone produced by conspecific femal...
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.0802610105
更新日期:2008-07-01 00:00:00
abstract::Ghrelin is a newly discovered peptide and an endogenous ligand for growth hormone (GH) secretagogue (GHS) receptor. It has been shown to possess various central and peripheral effects, including GH secretion, food intake, and gastric and cardiac effects. Ghrelin and the GHS receptor are expressed also in pancreatic 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.0502470102
更新日期:2006-01-24 00:00:00
abstract::Nerve growth factor has been quantified by both bioassay and radial immunodiffusion in mouse saliva elicited by several secretagogues. The concentrations by bioassay of nerve growth factor in both epinephrine- and norepinephrine-induced saliva (3400 and 900 mug/ml, respectively) are higher than reported in any other 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.73.11.4210
更新日期:1976-11-01 00:00:00
abstract::The recently discovered potato tuber (Solanum tuberosum) alpha-glucan, water dikinase (GWD) (formerly known as R1) catalyzes the phosphorylation of starch by a dikinase-type reaction mechanism in which the beta-phosphate of ATP is transferred to either the C-6 or the C-3 position of the glucosyl residue of starch. 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.0406674102
更新日期:2005-02-01 00:00:00
abstract::Observers have found a small number of lithium-depleted halo stars in the temperature range of the Spite plateau. The current status of the mass-loss hypothesis for producing the observed lithium dip in Population (Pop) I stars is briefly discussed and extended to Pop II stars as a possible explanation for these halo ...
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.94.10.4836
更新日期:1997-05-13 00:00:00
abstract::We have isolated and characterized the complete human villin gene. The villin gene is located on chromosome 2q35-36 in humans and on chromosome 1 in mice. Villin belongs to a family of calcium-regulated actin-binding proteins that share structural and functional homologies. The villin gene is expressed mainly in cells...
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.88.23.10811
更新日期:1991-12-01 00:00:00
abstract::MicroRNAs (miRNAs) are small (approximately 21 nt), noncoding RNAs that negatively regulate target mRNAs at the posttranscriptional level that are involved in development. In plants, virus-induced disease symptoms often result in developmental abnormalities resembling perturbation of miRNA-mediated function. Here, 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.0504439102
更新日期:2005-07-19 00:00:00
abstract::Recent studies of human disease and transgenic animal experiments have clearly demonstrated the importance of desmosomes in normal tissue architecture. Furthermore, desmosomal components are down-regulated in certain types of carcinomas, suggesting a possible role for desmosomes in suppression of invasion and metastas...
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.95.14.8064
更新日期:1998-07-07 00:00:00
abstract::For more than 50 y ecologists have believed that spatial heterogeneity in habitat conditions promotes species richness by increasing opportunities for niche partitioning. However, a recent stochastic model combining the main elements of niche theory and island biogeography theory suggests that environmental heterogene...
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.1208652109
更新日期:2012-10-23 00:00:00
abstract::The Ten-Eleven-Translocation 2 (TET2) gene encodes a member of TET family enzymes that alters the epigenetic status of DNA by oxidizing 5-methylcytosine to 5-hydroxymethylcytosine (5hmC). Somatic loss-of-function mutations of TET2 are frequently observed in patients with diverse myeloid malignancies, including myelody...
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.1112317108
更新日期:2011-08-30 00:00:00
abstract::Disruption of the nucleotide excision repair (NER) pathway by mutations can cause xeroderma pigmentosum, a syndrome predisposing affected individuals to development of skin cancer. The xeroderma pigmentosum C (XPC) protein is essential for initiating global genome NER by recognizing the DNA lesion and recruiting downs...
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.1010377108
更新日期:2010-12-28 00:00:00
abstract::Previous reports have shown that γδ T cells are important for the elimination of malaria parasites in humans and mice. However, how γδ T cells are involved in protective immunity against blood-stage malaria remains unknown. We infected γδ T-cell-deficient (TCRδ-KO) mice and control wild-type mice with Plasmodium bergh...
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.1204480109
更新日期:2012-07-24 00:00:00
abstract::Serotonin (5-HT) plays a critical role in modulating synaptic plasticity in the marine mollusc Aplysia and in the mammalian nervous system. In Aplysia sensory neurons, 5-HT can activate several signal cascades, including PKA and PKC, presumably via distinct types of G protein-coupled receptors. However, the molecular ...
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.0907502106
更新日期:2009-08-25 00:00:00
abstract::Ab initio multi-reference second-order perturbation theory computations are used to explore the photochemical behavior of two ion pairs constituted by a chloride counterion interacting with either a rhodopsin or bacteriorhodopsin chromophore model (i.e., the 4-cis-gamma-methylnona-2,4,6,8-tetraeniminium and all-trans-...
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.0408723102
更新日期:2005-05-03 00:00:00