Abstract:
:Although plants are photoautotrophic organisms, they are composed of many heterotrophic tissue systems that must import sugars and amino acids in a process known as assimilate partitioning. While the general features of assimilate partitioning were well described by the early 1980s, little was known about the various transport proteins involved in this essential activity associated with multicellular growth. In the past seven years, however, significant progress has been made in describing the transport properties and molecular genetics of these critical transport systems. Initially, these porters were well characterized using purified membrane vesicles and imposed proton electrochemical potential differences. This approach allowed for a detailed analysis of their transport kinetics, bioenergetics, and substrate specificity. Subsequently, several transporters were cloned using differential hybridization and functional complementation of yeast transport mutants. At first, isolation of transporter genes seemed to simplify our understanding by filling in gaps associated with transporter function. However, it has become increasingly clear that assimilate partitioning has many levels of complexity yet to be penetrated. This is best illustrated by the large number of carriers cloned. For example, at least 12 genes encoding putative sugar transporters in the Major Facilitator Superfamily have been identified in plants. Moreover, recent work in this laboratory has demonstrated that a sugar beet member of this superfamily is targeted to the tonoplast membrane, thus implicating that porter in intracellular sugar partitioning. Similar complexity is emerging in the number of plant amino acid transporters identified. Therefore, a detailed analysis of AAP1/NAT2 as a prototypical example of one class of amino acid carriers has been initiated. The topology of this porter is being mapped, and site-directed and random mutagenesis are being used to identify functionally important amino acid residues and protein domains. The major challenges facing this field are to determine the unique contributions made by these many transport systems, to understand their structure and function relationships and, ultimately, to identify the mechanisms which regulate activity and integrate assimilate distribution in the plant as a multicellular organism.
journal_name
J Exp Botjournal_title
Journal of experimental botanyauthors
Bush DR,Chiou TJ,Chen Ldoi
10.1093/jxb/47.Special_Issue.1205subject
Has Abstractpub_date
1996-08-01 00:00:00pages
1205-10eissn
0022-0957issn
1460-2431pii
47.Special_Issue.1205journal_volume
47 Spec Nopub_type
杂志文章abstract::Volatile organic compounds (VOCs) are major determinants of fruit flavor, a primary objective in tomato breeding. A recombinant inbred line (RIL) population consisting of 169 lines derived from a cross between Solanum lycopersicum and a red-fruited wild tomato species Solanum pimpinellifolium accession (SP) was charac...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/erw455
更新日期:2017-01-01 00:00:00
abstract::In order to understand the role of cytosolic antioxidant enzymes in drought stress protection, transgenic tobacco (Nicotiana tabacum cv. Xanthi) plants overexpressing cytosolic Cu/Zn-superoxide dismutase (cytsod) (EC 1.15.1.1) or ascorbate peroxidase (cytapx) (EC 1.11.1.1) alone, or in combination, were produced and t...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/erq432
更新日期:2011-05-01 00:00:00
abstract::This short review outlines the central role of glutamine synthetase (GS) in plant nitrogen metabolism and discusses some possibilities for crop improvement. GS functions as the major assimilatory enzyme for ammonia produced from N fixation, and nitrate or ammonia nutrition. It also reassimilates ammonia released as a ...
journal_title:Journal of experimental botany
pub_type: 杂志文章,评审
doi:10.1093/jexbot/53.370.979
更新日期:2002-04-01 00:00:00
abstract::That root system architecture (RSA) has an essential role in nitrogen acquisition is expected in maize, but the genetic relationship between RSA and nitrogen use efficiency (NUE) traits remains to be elucidated. Here, the genetic basis of RSA and NUE traits was investigated in maize using a recombination inbred line p...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/erv127
更新日期:2015-06-01 00:00:00
abstract::Cytokinins are one of the most important phytohormones and play essential roles in multiple life processes in planta. Root-derived cytokinins are transported to the shoots via long-distance transport. The mechanisms of long-distance transport of root-derived cytokinins remain to be demonstrated. In this study, we repo...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/erz382
更新日期:2019-11-18 00:00:00
abstract::Tomato, melon, grape, peach, and strawberry primarily accumulate soluble sugars during fruit development. In contrast, kiwifruit (Actinidia Lindl. spp.) and banana store a large amount of starch that is released as soluble sugars only after the fruit has reached maturity. By integrating metabolites measured by gas chr...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/ert293
更新日期:2013-11-01 00:00:00
abstract::Nitrogen-fixing bacteria have been isolated from sugarcane in an endophytic and beneficial interaction that promotes plant growth. In this work, for the first time, the involvement of ethylene signalling in this interaction was investigated by molecular characterizing members of this pathway in sugarcane. The expressi...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/erl242
更新日期:2007-01-01 00:00:00
abstract::High temperature stress (HTS), during flowering, decreases seed production in many plants. To determine the effect of a moderate HTS on flowering, fruit and seed set in Brassica napus, plants were exposed to a HTS (8/16 h dark/light, 18 degrees C night, ramped at 2 degrees C h-1, over 6 h, to 35 degrees C for 4 h, ram...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/erh038
更新日期:2004-02-01 00:00:00
abstract::Visual symptoms of the onset of senescence in Sandersonia aurantiaca flowers begin with fading of flower colour and wilting of the tissue. When fully senescent, the flowers form a papery shell that remains attached to the plant. The cell walls of these flowers have been examined to determine whether there are wall mod...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jexbot/53.368.513
更新日期:2002-03-01 00:00:00
abstract::Oxidative cleavage of cis-epoxycarotenoids by 9-cis-epoxycarotenoid dioxygenase (NCED) is the critical step in the regulation of abscisic acid (ABA) synthesis in higher plants. ABA has been associated with dormancy and flower senescence, while also regulating plant adaptive responses to various environmental stresses....
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/err293
更新日期:2012-01-01 00:00:00
abstract::Heavy metal pollution often occurs together with organic contaminants. Brassinosteroids (BRs) induce plant tolerance to several abiotic stresses, including phenanthrene (PHE) and cadmium (Cd) stress. However, the role of BRs in PHE+Cd co-contamination-induced stress amelioration is unknown. Here, the interactive effec...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/ers323
更新日期:2013-01-01 00:00:00
abstract::Plants have evolved and adapted to different environments. Dwarfism is an adaptive trait of plants that helps them avoid high-energy costs under unfavourable conditions. The role of gibberellin (GA) in plant development has been well established. Several plant dehydration-responsive element-binding proteins (DREBs) ha...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/ers295
更新日期:2012-11-01 00:00:00
abstract::Accounting for almost one-fifth of the primary production on Earth, the unicellular eukaryotic group of diatoms plays a key ecological and biogeochemical role in our contemporary oceans. Furthermore, as producers of various lipids and pigments, and characterized by their finely ornamented silica cell wall, diatoms hol...
journal_title:Journal of experimental botany
pub_type: 杂志文章,评审
doi:10.1093/jxb/ert387
更新日期:2014-06-01 00:00:00
abstract::The mechanism of the post-translational modulation of nitrate reductase activity (NR, EC 1.6.6.1) is briefly summarized, and it is shown that by this mechanism nitric oxide production through NR is also rapidly modulated. New and partly unexpected details on the modulation mechanism have been obtained by using immunol...
journal_title:Journal of experimental botany
pub_type: 杂志文章,评审
doi:10.1093/jexbot/53.370.875
更新日期:2002-04-01 00:00:00
abstract::Recent work has made progress in relating the size of stomata to stomatal functioning and, in particular, the speed of opening and closing and its implications. Calculations of the influence of stomatal size on the potential rate of osmolarity increase, assuming size-independent ion influx rate per unit area of guard ...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/eru032
更新日期:2014-04-01 00:00:00
abstract::Genes encoding pathogenesis-related (PR-) proteins isolated from a cDNA library of Fusarium graminearum-infected wheat spikes of scab-resistant cultivar 'Sumai-3' were transformed into susceptible spring wheat, 'Bobwhite' using a biolistic transformation protocol, with the goal of enhancing levels of resistance agains...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/erg110
更新日期:2003-03-01 00:00:00
abstract::At present and more so in the future, irrigated agriculture will take place under water scarcity. Insufficient water supply for irrigation will be the norm rather than the exception, and irrigation management will shift from emphasizing production per unit area towards maximizing the production per unit of water consu...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/erl165
更新日期:2007-01-01 00:00:00
abstract::Nitric oxide (NO) has been increasingly implicated as part of the ripening regulatory networks in fleshy fruits. However, very little is known about the simultaneous action of NO on the intertwined web of regulatory events and metabolic reactions behind the ripening-related changes in fruit color, taste, aroma and nut...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/eraa526
更新日期:2020-11-09 00:00:00
abstract::Contrary to the increasing amount of knowledge regarding the functional roles of glycine-rich RNA-binding proteins (GRPs) in Arabidopsis thaliana in stress responses, the physiological functions of GRPs in rice (Oryza sativa) currently remain largely unknown. In this study, the functional roles of six OsGRPs from rice...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/erq058
更新日期:2010-05-01 00:00:00
abstract::This perspective summarizes the presentations and discussions at the ' International Symposium on Synthetic Biology in Photosynthesis Research', which was held in Shanghai in 2018. Leveraging the current advanced understanding of photosynthetic systems, the symposium brain-stormed about the redesign and engineering of...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/eraa075
更新日期:2020-04-06 00:00:00
abstract::Dihydroflavonol 4-reductase (DFR) is the first committed enzyme of the anthocyanin and condensed tannin pathways. Several DFR cDNAs have been cloned, and different specificities of DFR isozymes in the substrate hydroxylation patterns have been reported, but only fragmentary knowledge of DFR gene organization is availa...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/eri251
更新日期:2005-09-01 00:00:00
abstract::Whole apple fruit (Malus domestica Borkh.) widely differing in pigment content and composition has been examined by recording its chlorophyll fluorescence excitation and diffuse reflection spectra in the visible and near UV regions. Spectral bands sensitive to the pigment concentration have been identified, and linear...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/erm316
更新日期:2008-01-01 00:00:00
abstract::A cDNA sequence coding for a pea (Pisum sativum L.) 2-Cys peroxiredoxin (2-Cys Prx) has been cloned. The deduced amino acid sequence showed a high sequence homology to the 2-Cys Prx enzymes of Phaseolus vulgaris (86%), Arabidopsis thaliana (75%), and Spinacia oleracea (75%), and contained a chloroplast target sequence...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/erh238
更新日期:2004-10-01 00:00:00
abstract::To elucidate the phytohormonal basis of the feedback regulation of leaf senescence induced by potassium (K) deficiency in cotton (Gossypium hirsutum L.), two cultivars contrasting in sensitivity to K deficiency were self- and reciprocally grafted hypocotyl-to-hypocotyl, using standard grafting (one scion grafted onto ...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/ers238
更新日期:2012-10-01 00:00:00
abstract::Iron (Fe) is vital for plant growth. Plants balance the beneficial and toxic effects of this micronutrient, and tightly control Fe uptake and allocation. Here, we review the role of the basic helix-loop-helix (bHLH) transcription factor FIT (FER-LIKE FE DEFICIENCY-INDUCED TRANSCRIPTION FACTOR) in Fe acquisition. FIT i...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/eraa012
更新日期:2020-03-12 00:00:00
abstract::The genomes of many plant viruses have a coding capacity limited to <10 proteins, yet it is becoming increasingly clear that individual plant virus proteins may interact with several targets in the host for establishment of infection. As new functions are uncovered for individual viral proteins, virologists have reali...
journal_title:Journal of experimental botany
pub_type: 杂志文章,评审
doi:10.1093/jxb/erv520
更新日期:2016-03-01 00:00:00
abstract::The efficient exclusion of excess Na from the cytoplasm and vacuolar Na(+) accumulation are the main mechanisms for the adaptation of plants to salt stress. This is typically carried out by transmembrane transport proteins that exclude Na(+) from the cytosol in exchange for H(+), a secondary transport process which is...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/erp011
更新日期:2009-01-01 00:00:00
abstract::Previous studies documented that metal hyperaccumulation armours plants with direct defences against pathogens. In the present study, it was found that high leaf Mn concentrations (<2500 µg g(-1)) induced grapevine resistance to powdery mildew [Uncinula necator (Schw.) Burr]. Manganese delayed pathogen spreading after...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jxb/ers175
更新日期:2012-09-01 00:00:00
abstract::When plants encounter compacted soil, stomatal closure occurs and shoot growth slows. These responses occur in the absence of detectable changes in foliar water status. The use of genotypes with a reduced capacity to synthesize either ABA or ethylene has provided convincing evidence that ABA is responsible for providi...
journal_title:Journal of experimental botany
pub_type: 杂志文章,评审
doi:
更新日期:2002-01-01 00:00:00
abstract::Seed germination is often induced by a pulse of red light perceived by phytochrome and cancelled by a subsequent pulse of far-red light. When the pulse of red light is followed by several hours of darkness, a pulse of far-red light is no longer effective and prolonged far-red is necessary to block germination. The aim...
journal_title:Journal of experimental botany
pub_type: 杂志文章
doi:10.1093/jexbot/51.347.1127
更新日期:2000-06-01 00:00:00