Abstract:
:Overexpression of the Gossypium hirsutum sucrose synthase (SuSy) gene under the control of 2 promoters was examined in hybrid poplar (Populus alba x grandidentata). Analysis of RNA transcript abundance, enzyme activity, cell wall composition, and soluble carbohydrates revealed significant changes in the transgenic lines. All lines showed significantly increased SuSy enzyme activity in developing xylem. This activity manifested in altered secondary cell wall cellulose content per dry weight in all lines, with increases of 2% to 6% over control levels, without influencing plant growth. The elevated concentration of cellulose was associated with an increase in cell wall crystallinity but did not alter secondary wall microfibril angle. This finding suggests that the observed increase in crystallinity is a function of altered carbon partitioning to cellulose biosynthesis rather than the result of tension wood formation. Furthermore, the augmented deposition of cellulose in the transgenic lines resulted in thicker xylem secondary cell wall and consequently improved wood density. These findings clearly implicate SuSy as a key regulator of sink strength in poplar trees and demonstrate the tight association of SuSy with cellulose synthesis and secondary wall formation.
journal_name
Proc Natl Acad Sci U S Aauthors
Coleman HD,Yan J,Mansfield SDdoi
10.1073/pnas.0900188106subject
Has Abstractpub_date
2009-08-04 00:00:00pages
13118-23issue
31eissn
0027-8424issn
1091-6490pii
0900188106journal_volume
106pub_type
杂志文章abstract::Here, we describe the identification and characterization of a nuclear body (matrix-associated deacetylase body) whose formation and integrity depend on deacetylase activity. Typically, there are 20-40 0.5-microM bodies per nucleus, although the size and number can vary substantially. The structure appears to contain ...
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.97.19.10330
更新日期:2000-09-12 00:00:00
abstract::The mechanism underlying how transcription factors regulate mesenchymal stem cell lineage commitment remains unclear. To determine the role of core-binding factor subunit beta (Cbfβ) in osteoblast lineage commitment, we generated three mouse models by deleting Cbfβ at different osteoblast lineage stages. We demonstrat...
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.1619294114
更新日期:2017-09-19 00:00:00
abstract::Recently, a 29-residue cyclic peptide was synthesized (TrPepz) that was reported to possess nearly the same catalytic activity and specificity as the pancreatic serine protease, trypsin, for hydrolysis of a small ester substrate, N-tosyl-L-arginine methyl ester (TAME), and small and large peptides [Atassi, M. Z. & Man...
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.91.10.4110
更新日期:1994-05-10 00:00:00
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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.1809004115
更新日期:2018-10-02 00:00:00
abstract::Extracts of Escherichia coli strains infected with bacteriophage phiX174 catalyze DNA synthesis dependent on double-stranded, circular phiX174 replicative form I (phiX RFI) by a semiconservative process. The reaction required Mg++, ATP, all four dNTP, and exogenous phiX RFI DNA as template and yielded phiX RFI and phi...
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.73.6.1887
更新日期:1976-06-01 00:00:00
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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.242625399
更新日期:2002-12-10 00:00:00
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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.95.21.12410
更新日期:1998-10-13 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2018-05-22 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.92.19.8798
更新日期:1995-09-12 00:00:00
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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.0706700105
更新日期:2008-04-01 00:00:00
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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.83.11.3684
更新日期:1986-06-01 00:00:00
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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.75.12.6002
更新日期:1978-12-01 00:00:00
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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.1913284117
更新日期:2020-02-11 00:00:00
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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.92.13.6007
更新日期:1995-06-20 00:00:00
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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.1600965113
更新日期:2016-08-02 00:00:00
abstract::Amorphous silicon oxycarbide polymer-derived ceramics (PDCs), synthesized from organometallic precursors, contain carbon- and silica-rich nanodomains, the latter with extensive substitution of carbon for oxygen, linking Si-centered SiO(x)C(4-x) tetrahedra. Calorimetric studies demonstrated these PDCs to be thermodynam...
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.1312771110
更新日期:2013-10-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2010-01-05 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2008-11-25 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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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.82.17.5963
更新日期:1985-09-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1999-10-12 00:00:00
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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.78.9.5712
更新日期:1981-09-01 00:00:00
abstract::There is a high mortality in patients with diabetes and severe pressure ulcers. For example, chronic pressure sores of the heels often lead to limb loss in diabetic patients. A major factor underlying this is reduced neovascularization caused by impaired activity of the transcription factor hypoxia inducible factor-1 ...
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.1413445112
更新日期:2015-01-06 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2017-09-19 00:00:00
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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.91.11.4629
更新日期:1994-05-24 00:00:00
abstract::The human fungal pathogen Candida albicans shows a significant lag in growth when diluted into fresh minimal medium. This lag is abolished by the addition of conditioned medium from a high-density culture. The active component of conditioned medium is tyrosol, which is released into the medium continuously during grow...
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.0401416101
更新日期:2004-04-06 00:00:00
abstract::Deleting an important active-site residue of diphtheria toxin, glutamic acid-148, reduces the toxin's ADP-ribosyltransferase activity by a factor of greater than 10(4). We considered using this mutation to construct a recombinant toxoid for expression by live attenuated vaccines and explored second-site mutations that...
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.89.13.6207
更新日期:1992-07-01 00:00:00
abstract::Deletion of 13 amino acids from the carboxyl terminus of the 149-amino acid staphylococcal nuclease molecule results in a denatured, partly unfolded molecule that lacks persistent secondary structure but is compact under physiological conditions. Since the modification is a carboxyl-terminal deletion, it is argued tha...
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.89.2.748
更新日期:1992-01-15 00:00:00
abstract::The physiological significance of multiple G-protein-coupled receptor subtypes, such as the beta-adrenergic receptors (beta ARs), remains obscure, since in many cases several subtypes activate the same effector and utilize the same physiological agonists. We inspected the deduced amino acid sequences of the beta AR su...
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.90.8.3665
更新日期:1993-04-15 00:00:00