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You searched for: Journal Proceedings of the National Academy of Sciences of the United States of America Remove constraint Journal: Proceedings of the National Academy of Sciences of the United States of America Publication Year 2002 Remove constraint Publication Year: 2002 Source 2002 v.99 no.25 Remove constraint Source: 2002 v.99 no.25
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1. African rice (Oryza glaberrima): history and future potential

Author:
Linares, O.F.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16360-16365
ISSN:
0027-8424
Subject:
history; interspecific variation; crop production; rice; ethnobotany; Oryza sativa; varieties; flooded conditions; Oryza glaberrima; interspecific hybridization; Senegal
Abstract:
... The African species of rice (Oryza glaberrima) was cultivated long before Europeans arrived in the continent. At present, O. glaberrima is being replaced by the introduced Asian species of rice, Oryza sativa. Some West African farmers, including the Jola of southern Senegal, still grow African rice for use in ritual contexts. The two species of rice have recently been crossed, producing a promisin ...
DOI:
10.1073/pnas.252604599
PubMed:
12461173
PubMed Central:
PMC138616

2. AGAMOUS-LIKE 24, a dosage-dependent mediator of the flowering signals

Author:
Yu, H.; Xu, Y.; Tan, E.L.; Kumar, P.P.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16336-16341
ISSN:
0027-8424
Subject:
Arabidopsis thaliana; transcription factors; apical meristems; flowering; regulator genes; gene overexpression; mutants; shoot meristems; RNA
Abstract:
... The most dramatic phase change in plants is the transition from vegetative to reproductive growth. This flowering process is regulated by several interacting pathways that monitor both the developmental state of the plants and environmental cues such as light and temperature. The flowering-time genes FLOWERING LOCUS T (FT) and SUPPRESSOR OF OVEREXPRESSION OF CO1 (SOC1), together with the floral me ...
DOI:
10.1073/pnas.212624599
PubMed:
12451184
PubMed Central:
PMC138612

3. A new role for an old enzyme: nitrate reductase-mediated nitric oxide generation is required for abscisic acid-induced stomatal closure in Arabidopsis thaliana

Author:
Desikan, R.; Griffiths, R.; Hancock, J.; Neill, S.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16314-16318
ISSN:
0027-8424
Subject:
Arabidopsis thaliana; stomatal movement; nitric oxide; nitrate reductase; enzyme activity; abscisic acid; nitrites; guard cells; mutants; phenotype
Abstract:
... The plant hormone abscisic acid (ABA), synthesized in response to water-deficit stress, induces stomatal closure via activation of complex signaling cascades. Recent work has established that nitric oxide (NO) is a key signaling molecule mediating ABA-induced stomatal closure. However, the biosynthetic origin of NO in guard cells has not yet been resolved. Here, we provide pharmacological, physiol ...
DOI:
10.1073/pnas.252461999
PubMed:
12446847
PubMed Central:
PMC138608

4. A pectin glucuronyltransferase gene is essential for intercellular attachment in the plant meristem

Author:
Iwai, H.; Masaoka, N.; Ishii, T.; Satoh, S.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16319-16324
ISSN:
0027-8424
Subject:
apical meristems; hexosyltransferases; carbohydrate metabolism; glucuronic acid; phenotype; pectins; gene expression; genes; mutants; nucleotide sequences; root meristems; shoot meristems; Nicotiana plumbaginifolia
Abstract:
... Intercellular attachment is an essential process in the morphogenesis of multicellular organisms. A unique mutant, nolac-H18 (nonorganogenic callus with loosely attached cells), generated by T-DNA transformation using leaf-disk cultures of haploid Nicotiana plumbaginifolia, lost the ability to form tight intercellular attachments and adventitious shoots. The gene tagged with T-DNA, named NpGUT1 (g ...
DOI:
10.1073/pnas.252530499
PubMed:
12451175
PubMed Central:
PMC138609

5. A subclass of plant heat shock cognate 70 chaperones carries a motif that facilitates trafficking through plasmodesmata

Author:
Aoki, K.; Kragler, F.; Xoconostle-Cazares, B.; Lucas, W.J.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16342-16347
ISSN:
0027-8424
Subject:
Cucurbita maxima; Nicotiana tabacum; plant proteins; heat shock proteins; binding proteins; adenosinetriphosphatase; plasmodesmata; protein transport; phloem; sap; complementary DNA; nucleotide sequences; translocation (plant physiology)
Abstract:
... Plasmodesmata establish a pathway for the trafficking of non-cell-autonomously acting proteins and ribonucleoprotein complexes. Plasmodesmal enriched cell fractions and the contents of enucleate sieve elements, in the form of phloem sap, were used to isolate and characterize heat shock cognate 70 (Hsc70) chaperones associated with this cell-to-cell transport pathway. Three Cucurbita maxima Hsc70 c ...
DOI:
10.1073/pnas.252427999
PubMed:
12456884
PubMed Central:
PMC138613

6. Characteristic genome rearrangements in experimental evolution of Saccharomyces cerevisiae

Author:
Dunham, M.J.; Badrane, H.; Ferea, T.; Adams, J.; Brown, P.O.; Rosenzweig, F.; Botstein, D.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16144-16149
ISSN:
0027-8424
Subject:
Saccharomyces cerevisiae; cultured cells; evolution; aneuploidy; chromosome translocation; chromosomes; transposons; chromosome breakage
Abstract:
... Genome rearrangements, especially amplifications and deletions, have regularly been observed as responses to sustained application of the same strong selective pressure in microbial populations growing in continuous culture. We studied eight strains of budding yeast (Saccharomyces cerevisiae) isolated after 100-500 generations of growth in glucose-limited chemostats. Changes in DNA copy number wer ...
DOI:
10.1073/pnas.242624799
PubMed:
12446845
PubMed Central:
PMC138579

7. Conflict between nuclear and mitochondrial DNA phylogenies of a recent species radiation: what mtDNA reveals and conceals about modes of speciation in Hawaiian crickets

Author:
Shaw, K.L.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16122-16127
ISSN:
0027-8424
Subject:
mitochondrial DNA; phylogeny; nuclear genome; genes; nucleotide sequences; Gryllidae; Hawaii
Abstract:
... It has been asserted that recent mtDNA phylogenies support the plausibility of sympatric speciation, long considered a controversial mechanism of the origin of species. If such inferences are reliable, mtDNA phylogenies should be congruent with phylogenies based on other data. In previous work, a mtDNA phylogeny suggested that diversification of the Hawaiian cricket genus Laupala was initiated by ...
DOI:
10.1073/pnas.242585899
PubMed:
12451181
PubMed Central:
PMC138575

8. Disruption of Abcg5 and Abcg8 in mice reveals their crucial role in biliary cholesterol secretion

Author:
Yu, L.; Hammer, R.E.; Li-Hawkins, J.; Bergmann, K. von.; Lutjohann, D.; Cohen, J.C.; Hobbs, H.H.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16237-16242
ISSN:
0027-8424
Subject:
phytosterols; blood lipids; phenotype; secretion; mice; cholesterol; intestinal absorption; genes; mutants; bile; feces; blood plasma; animal models; bile acids; lipid metabolism disorders; ABC transporters; phospholipids
Abstract:
... Cholesterol and other sterols exit the body primarily by secretion into bile. In patients with sitosterolemia, mutations in either of two ATP-binding cassette (ABC) half-transporters, ABCG5 or ABCG8, lead to reduced secretion of sterols into bile, implicating these transporters in this process. To elucidate the roles of ABCG5 and ABCG8 in the trafficking of sterols, we disrupted Abcg5 and Abcg8 in ...
DOI:
10.1073/pnas.252582399
PubMed:
12444248
PubMed Central:
PMC138595

9. Enhanced muscle fat oxidation and glucose transport by ACRP30 globular domain: acetyl-CoA carboxylase inhibition and AMP-activated protein kinase activation

Author:
Tomas, E.; Tsao, T.S.; Saha, A.K.; Murrey, H.E.; Zhang, C.C.; Itani, S.I.; Lodish, H.F.; Ruderman, N.B.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16309-16313
ISSN:
0027-8424
Subject:
hormones; adipocytes; enzyme activity; phosphorylation; adenosine monophosphate; acetyl-CoA carboxylase; lipolysis; fatty acids; oxidation; glucose; active transport; skeletal muscle; esters; rats; mice
Abstract:
... gACRP30, the globular subunit of adipocyte complement-related protein of 30 kDa (ACRP30), improves insulin sensitivity and increases fatty acid oxidation. The mechanism by which gACRP30 exerts these effects is unknown. Here, we examined if gACRP30 activates AMP-activated protein kinase (AMPK), an enzyme that has been shown to increase muscle fatty acid oxidation and insulin sensitivity. Incubation ...
DOI:
10.1073/pnas.222657499
PubMed:
12456889
PubMed Central:
PMC138607

10. Functional complementation of yeast cytosolic pyrophosphatase by bacterial and plant H+-translocating pyrophosphatases

Author:
Perez-Castineira, J.R.; Lopez-Marques, R.L.; Villalba, J.M.; Losada, M.; Serrano, A.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 15914-15919
ISSN:
0027-8424
Subject:
Saccharomyces cerevisiae; mutants; inorganic pyrophosphatase; Arabidopsis thaliana; genes; bacteria; enzyme activity; ion transport; hydrogen ions; gene expression; messenger RNA; genetic complementation; plasma membrane; Chloroflexus aurantiacus
Abstract:
... Two types of proteins that hydrolyze inorganic pyrophosphate (PP(i)), very different in both amino acid sequence and structure, have been characterized to date: soluble and membrane-bound proton-pumping pyrophosphatases (sPPases and H(+)-PPases, respectively). sPPases are ubiquitous proteins that hydrolyze PP(i) releasing heat, whereas H(+)-PPases, so far unidentified in animal and fungal cells, c ...
DOI:
10.1073/pnas.242625399
PubMed:
12451180
PubMed Central:
PMC138539

11. In vitro reconstitution of the activated zeaxanthin state associated with energy dissipation in plants

Author:
Aspinall-O'Dea, M.; Wentworth, M.; Pascal, A.; Robert, B.; Ruban, A.; Horton, P.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16331-16335
ISSN:
0027-8424
Subject:
Spinacia oleracea; photosystem II; zeaxanthin; energy; plant proteins; binding proteins; absorbance; electron transfer
Abstract:
... Dissipation of excess light energy in plant photosynthetic membranes plays an important role in the response of plants to the environment, providing short-term balancing between the intensity of sunlight and photosynthetic capacity. The carotenoid zeaxanthin and the photosystem II subunit PsbS play vital roles in this process, but the mechanism of their action is largely unexplained. Here we repor ...
DOI:
10.1073/pnas.252500999
PubMed:
12461177
PubMed Central:
PMC138611

12. Large-scale comparison of intron positions among animal, plant, and fungal genes

Author:
Fedorov, A.; Merican, A.F.; Gilbert, W.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16128-16133
ISSN:
0027-8424
Subject:
interspecific variation; animals; evolution; computer analysis; introns; databases; fungi
Abstract:
... We purge large databases of animal, plant, and fungal intron-containing genes to a 20% similarity level and then identify the most similar animal-plant, animal-fungal, and plant-fungal protein pairs. We identify the introns in each BLAST 2.0 alignment and score matched intron positions and slid (near-matched, within six nucleotides) intron positions automatically. Overall we find that 10% of the a ...
DOI:
10.1073/pnas.242624899
PubMed:
12444254
PubMed Central:
PMC138576

13. Loci on chromosomes 14 and 2, distinct from ABCG5/ABCG8, regulate plasma plant sterol levels in a C57BL/6J x CASA/Rk intercross

Author:
Sehayek, E.; Duncan, E.M.; Lutjohann, D.; Bergmann, K. von.; Ono, J.G.; Batta, A.K.; Salen, G.; Breslow, J.L.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16215-16219
ISSN:
0027-8424
Subject:
loci; blood chemistry; gene interaction; crossing; mice; cholesterol; chromosome mapping; inheritance (genetics); campesterol; strains
Abstract:
... Plasma plant sterol levels differ among humans due to genetic and dietary factors. A disease characterized by high plasma plant sterol levels, beta-sitosterolemia, was recently found to be due to mutations at the ABCG5/ABCG8 locus. To detect variants at this and other loci, a genetic cross was carried out between two laboratory mouse strains. Parental C57BL/6J had almost twice the campesterol and ...
DOI:
10.1073/pnas.212640599
PubMed:
12446833
PubMed Central:
PMC138591

14. Penelope retroelements from Drosophila virilis are active after transformation of Drosophila melanogaster

Author:
Pyatkov, K.I.; Shostak, N.G.; Zelentsova, E.S.; Lyozin, G.T.; Melekhin, M.I.; Finnegan, D.J.; Kidwell, M.G.; Evgen'ev, M.B.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16150-16155
ISSN:
0027-8424
Subject:
Drosophila melanogaster; Drosophila virilis; retrotransposons; genetic transformation; germ cells; gene expression; messenger RNA; heterochromatin; chromosome mapping; transcription (genetics); nucleic acid hybridization; in situ hybridization
Abstract:
... The Penelope family of retroelements was first described in species of the Drosophila virilis group. Intact elements encode a reverse transcriptase and an endonuclease of the UvrC type, which may play a role in Penelope integration. Penelope is a key element in the induction of D. virilis hybrid dysgenesis, which involves the mobilization of several unrelated families of transposable elements. We ...
DOI:
10.1073/pnas.252641799
PubMed:
12451171
PubMed Central:
PMC138580

15. Plant cell adhesion: a bioassay facilitates discovery of the first pectin biosynthetic gene

Author:
Lord, E.M.; Mollet, J.C.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 15843-15845
ISSN:
0027-8424
Subject:
hexosyltransferases; carbohydrate metabolism; pectins; bioassays; cells; genes; adhesion
DOI:
10.1073/pnas.012685099
PubMed:
12461188
PubMed Central:
PMC138523

16. RNA interference-mediated silencing of Sod2 in Drosophila leads to early adult-onset mortality and elevated endogenous oxidative stress

Author:
Kirby, K.; Hu, J.; Hilliker, A.J.; Phillips, J.P.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16162-16167
ISSN:
0027-8424
Subject:
electron transport chain; messenger RNA; superoxide dismutase; gene expression; genes; mitochondria; oxidation; aconitate hydratase; Drosophila melanogaster; mortality
Abstract:
... Oxidative stress has been widely implicated as an important factor in the aging process. Because mitochondrial respiration is the principal source of reactive oxygen within cells, the mitochondrially localized superoxide dismutase (SOD) 2 is thought to play an important front-line defensive role against aging-related oxidative stress. Although genetic studies with mutants deficient in SOD1, the pr ...
DOI:
10.1073/pnas.252342899
PubMed:
12456885
PubMed Central:
PMC138582

17. Studies on the function of oligosaccharyl transferase subunits: a glycosylatable photoprobe binds to the luminal domain of Ost1p

Author:
Yan, Q.; Lennarz, W.J.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 15994-15999
ISSN:
0027-8424
Subject:
Saccharomyces cerevisiae; hexosyltransferases; polypeptides; amino acid sequences; mutagenesis; mutants; binding sites
Abstract:
... Oligosaccharyl transferase (OT) is a complex multisubunit enzyme that, in the case of Saccharomyces cerevisiae, contains nine different transmembrane proteins. One of our goals is to identify the OT subunit(s) responsible for recognizing the consensus sequence, -Asn-X-Thr/Ser-, and catalyzing the oligosaccharide transfer reaction. By using a substrate-based photoprobe, earlier we found that Ost1p ...
DOI:
10.1073/pnas.212637999
PubMed:
12444261
PubMed Central:
PMC138553

18. Transgenic barley grain overexpressing thioredoxin shows evidence that the starchy endosperm communicates with the embryo and the aleurone

Author:
Wong, J.H.; Kim, Y.B.; Ren, P.H.; Cai, N.; Cho, M.J.; Hedden, P.; Lemaux, P.G.; Buchanan, B.B.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 16325-16330
ISSN:
0027-8424
Subject:
seed germination; seedling growth; gene overexpression; Hordeum vulgare; transgenic plants; aleurone layer; endosperm; gibberellins; enzyme activity; alpha-amylase; plant proteins
Abstract:
... Homozygous lines of barley overexpressing a wheat thioredoxin h transgene (up to 30-fold) were generated earlier by using a B1-hordein promoter with a signal peptide sequence for targeting to the protein body and found to be enriched in starch debranching enzyme (pullulanase). Here, we describe the effect of biochemically active, overexpressed thioredoxin h on germination and the onset of alpha-am ...
DOI:
10.1073/pnas.212641999
PubMed:
12456891
PubMed Central:
PMC138610

19. Trehalose accumulation in rice plants confers high tolerance levels to different abiotic stresses

Author:
Garg, A.K.; Kim, J.K.; Owens, T.G.; Ranwala, A.P.; Choi, Y.D.; Kochian, L.V.; Wu, R.J.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2002 v.99 no.25 pp. 15898
ISSN:
0027-8424
Subject:
Oryza sativa; transgenic plants; gene transfer; genetic transformation; Escherichia coli; genes; recombinant DNA; phosphoric monoester hydrolases; hexosyltransferases; trehalose; carbohydrate metabolism; gene expression; salt tolerance; drought tolerance; cold tolerance; photosynthesis; chemical constituents of plants; gene overexpression
Abstract:
... Trehalose is a nonreducing disaccharide of glucose that functions as a compatible solute in the stabilization of biological structures under abiotic stress in bacteria, fungi, and invertebrates. With the notable exception of the desiccation-tolerant "resurrection plants," trehalose is not thought to accumulate to detectable levels in most plants. We report here the regulated overexpression of Esch ...
Handle:
10113/13783
DOI:
10.1073/pnas.252637799
PubMed:
12456878
PubMed Central:
PMC138536