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941.
The citrus fruit proteome: insights into citrus fruit metabolism 总被引:1,自引:0,他引:1
Fruit development and ripening are key processes in the production of the phytonutrients that are essential for a balanced diet and for disease prevention. The pathways involved in these processes are unique to plants and vary between species. Climacteric fruit ripening, especially in tomato, has been extensively studied; yet, ripening of non-climacteric fruit is poorly understood. Although the different species share common pathways; developmental programs, physiological, anatomical, biochemical composition and structural differences must contribute to the operation of unique pathways, genes and proteins. Citrus has a non-climacteric fruit ripening behavior and has a unique anatomical fruit structure. For the last few years a citrus genome-wide ESTs project has been initiated and consists of 222,911 clones corresponding to 19,854 contigs and 37,138 singletons. Taking advantage of the citrus database we analyzed the citrus proteome. Using LC-MS/MS we analyzed soluble and enriched membrane fractions of mature citrus fruit to identify the proteome of fruit juice cells. We have identified ca. 1,400 proteins from these fractions by searching NCBI-nr (green plants) and citrus ESTs databases, classified these proteins according to their putative function and assigned function according to known biosynthetic pathways. 相似文献
942.
Forouhar F Kuzin A Seetharaman J Lee I Zhou W Abashidze M Chen Y Yong W Janjua H Fang Y Wang D Cunningham K Xiao R Acton TB Pichersky E Klessig DF Porter CW Montelione GT Tong L 《Journal of structural and functional genomics》2007,8(2-3):37-44
Structural genomics efforts have produced structural information, either directly or by modeling, for thousands of proteins
over the past few years. While many of these proteins have known functions, a large percentage of them have not been characterized
at the functional level. The structural information has provided valuable functional insights on some of these proteins, through
careful structural analyses, serendipity, and structure-guided functional screening. Some of the success stories based on
structures solved at the Northeast Structural Genomics Consortium (NESG) are reported here. These include a novel methyl salicylate
esterase with important role in plant innate immunity, a novel RNA methyltransferase (H. influenzae yggJ (HI0303)), a novel spermidine/spermine N-acetyltransferase (B. subtilis PaiA), a novel methyltransferase or AdoMet binding protein (A. fulgidus AF_0241), an ATP:cob(I)alamin adenosyltransferase (B. subtilis YvqK), a novel carboxysome pore (E. coli EutN), a proline racemase homolog with a disrupted active site (B. melitensis BME11586), an FMN-dependent enzyme (S. pneumoniae SP_1951), and a 12-stranded β-barrel with a novel fold (V. parahaemolyticus VPA1032). 相似文献
943.
Park SH Kim CM Je BI Park SH Park SJ Piao HL Xuan YH Choe MS Satoh K Kikuchi S Lee KH Cha YS Ahn BO Ji HS Yun DW Lee MC Suh SC Eun MY Han CD 《Planta》2007,227(1):1-12
OSH6 (Oryza sativa Homeobox6) is an ortholog of lg3 (Liguleless3) in maize. We generated a novel allele, termed OSH6-Ds, by inserting a defective Ds element into the third exon of OSH6, which resulted in a truncated OSH6 mRNA. The truncated mRNA was expressed ectopically in leaf tissues and encoded the N-terminal region of OSH6, which includes
the KNOX1 and partial KNOX2 subdomains. This recessive mutant showed outgrowth of bracts or produced leaves at the basal node
of the panicle. These phenotypes distinguished it from the OSH6 transgene whose ectopic expression led to a “blade to sheath transformation” phenotype at the midrib region of leaves, similar
to that seen in dominant Lg3 mutants. Expression of a similar truncated OSH6 cDNA from the 35S promoter (35S::ΔOSH6) confirmed that the ectopic expression of this product was responsible for the aberrant bract development. These data suggest
that OSH6-Ds interferes with a developmental mechanism involved in bract differentiation, especially at the basal nodes of panicles.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
944.
The tomato geneRSI-1 was previously identified as a molecular marker for auxin-induced lateral root initiation. We have further characterized
the expression mode of theRSI-1 gene in tomato andArabidopsis thaliana. Northern blot analyses revealed that the gene was induced specifically by auxin in tomato roots and hypocotyls. For experiments
with transgenic plants, the 5′ flanking region of theRSI-1 gene was linked to a GUS reporter gene, then transformed into tomato andArabidopsis. In these transgenic tomato plants, GUS activity was detected at the sites of initiation for lateral and adventitious roots.
Expression of the fusion gene was auxin-dependent and tissue-specific. This was consistent with results from the northern
blot analyses. In transgenicArabidopsis, the overall expression pattern of theRSI-GUS gene, including tissue specificity and auxin inducibility, was comparable to that in transgenic tomato seedlings. These results
indicate that an identical regulatory mechanism for lateral root initiation might be conserved in both plants. Thus, the expression
mode of theRSI-CUS gene inArabidopsis mutants defective in lateral root development should be investigated to provide details of this process. 相似文献
945.
Studies of the helix‐to‐coil transition in dilute solutions of poly‐L ‐lysine, dissolved in mixtures of water and methanol (MeOH), have been carried under shear flow using flow birefringence and modulated polarimetry. The fraction of helical conformations in a given solution remains independent of shear rate for MeOH concentrations above and below the critical value for the helix‐coil transition (i.e., 87.5% MeOH). For the 87.5% MeOH solutions, a shear‐induced helix‐to‐“stretched” coil transition occurs above a critical shear rate. Induction times for the transition show a temperature and shear rate dependence that can be described in terms of an activated jump process. Measurements of circular birefringence on cessation of flow also show that the transition is reversible, with the stretched coil reverting to the helical state on a time scale of several seconds. The activation energy for the jump process is found to be 16.2 kJ/mole. © 1999 John Wiley & Sons, Inc. Biopoly 50: 589–594, 1999 相似文献
946.
Eun Hye Lee Seon Sook Kim Seul Lee Kwan-Hyuck Baek Su Ryeon Seo 《The Journal of biological chemistry》2015,290(34):21019-21031
Pituitary adenylate cyclase-activating peptide (PACAP) is a neurotrophic peptide involved in a wide range of nervous functions, including development, differentiation, and survival, and various aspects of learning and memory. Here we report that PACAP induces the expression of regulator of calcineurin 1 (RCAN1, also known as DSCR1), which is abnormally expressed in the brains of Down syndrome patients. Increased RCAN1 expression is accompanied by activation of the PKA-cAMP response element-binding protein pathways. EMSA and ChIP analyses demonstrate the presence of a functional cAMP response element in the RCAN1 promoter. Moreover, we show that PACAP-dependent neuronal differentiation is significantly disturbed by improper RCAN1 expression. Our data provide the first evidence of RCAN1, a Down syndrome-related gene, as a novel target for control of the neurotrophic function of PACAP. 相似文献
947.
Geon Ha Kim Seun Jeon Kiho Im Hunki Kwon Byung Hwa Lee Ga Young Kim Hana Jeong Noh Eul Han Sang Won Seo Hanna Cho Young Noh Sang Eon Park Hojeong Kim Jung Won Hwang Cindy W. Yoon Hee Jin Kim Byoung Seok Ye Ju Hee Chin Jung-Hyun Kim Mee Kyung Suh Jong Min Lee Sung Tae Kim Mun-Taek Choi Mun Sang Kim Kenneth M Heilman Jee Hyang Jeong Duk L. Na 《PloS one》2015,10(4)
The purpose of this study was to investigate if multi-domain cognitive training, especially robot-assisted training, alters cortical thickness in the brains of elderly participants. A controlled trial was conducted with 85 volunteers without cognitive impairment who were 60 years old or older. Participants were first randomized into two groups. One group consisted of 48 participants who would receive cognitive training and 37 who would not receive training. The cognitive training group was randomly divided into two groups, 24 who received traditional cognitive training and 24 who received robot-assisted cognitive training. The training for both groups consisted of daily 90-min-session, five days a week for a total of 12 weeks. The primary outcome was the changes in cortical thickness. When compared to the control group, both groups who underwent cognitive training demonstrated attenuation of age related cortical thinning in the frontotemporal association cortices. When the robot and the traditional interventions were directly compared, the robot group showed less cortical thinning in the anterior cingulate cortices. Our results suggest that cognitive training can mitigate age-associated structural brain changes in the elderly.
Trial Registration
ClnicalTrials.gov NCT01596205 相似文献948.
This study investigated behavioral syndromes, which are defined as correlations between behaviors. Behavioral syndromes can
lead to the unintentional alteration of a wide range of behavioral traits of hatchery fish if unintentional selection on one
behavior leads to selection on a correlated behavior. Specifically, this study used brown rockfish, Sebastes auriculatus, to test the hypothesis that a fish that feeds at high rates in the absence of a predator also takes more risks when a predator
is present, and that through such a correlation, unintentional hatchery selection for high feeding rates may also lead to
changes in risk taking behavior (here defined as behavior that increases predation risk). Behavioral syndromes were found—feeding
behavior in the absence of a predator tended to correlate positively with both feeding behavior in the presence of a predator
model and time near the model. These syndromes were stable through time—that is, the same correlations appeared 10 days later
when the behavioral assays were repeated. However individual behavior was inconsistent (plastic). A fish could both feed and
take risks at high rates on Day 1, but then both feed and take risks at low rates on Day 10. Thus, while behavioral syndromes
were stable (i.e. present in both rounds 1 and 2), individuals were plastic in their behavior (i.e. inconsistent between rounds
1 and 2). After 16 weeks of hatchery rearing, neither growth nor survival were predicted by behavior. It is suggested that
the behavioral plasticity within individuals through time makes consistent selection for strong feeders less likely, and that
species with more plastic behavior may be less susceptible to unintentional selection on behavioral syndromes than species
with behavior that is more fixed. 相似文献
949.
Gap junctions are clusters of intercellular channels that are associated with embryonic development and neural signaling. Innexins, invertebrate gap junction proteins, have been identified in Drosophila and Caenorhabditis. Here, we report the isolation and characterization of two novel members of the insect innexin family, Bm inx2 and Bm inx4, from embryos of the silkworm, Bombyx mori, during the germ-band formation stage. Bm inx2 is a single copy gene with one exon, while Bm inx4 is a single copy gene with four exons and three introns. The predicted proteins show structural similarities with other innexin family members, including four transmembrane (TM) domains, two extracellular loops (ELs), one cytoplasmic loop (CL), and typical conserved amino acids. Bm inx2 is phylogenetically orthologous to the other insect inx2 genes, but Bm inx4 is not orthologous to any known innexin including Dm inx4. Interestingly, Northern blotting and in situ hybridization showed that Bm inx2 was variously expressed across all developmental stages and in various tissues, with high expression seen in the nervous system at the time of embryogenesis. In contrast, Bm inx4 was transiently expressed at the germ-band formation stage of embryogenesis, and was specifically expressed in the ovary and testis during the larval and pupal stages. The isolation and characterization of these novel genes should form the basis for further study of the functional events that occur during development and neuronal communication in B. mori. 相似文献
950.
Yang KJ Shin S Piao L Shin E Li Y Park KA Byun HS Won M Hong J Kweon GR Hur GM Seok JH Chun T Brazil DP Hemmings BA Park J 《The Journal of biological chemistry》2008,283(3):1480-1491
3-Phosphoinositide-dependent protein kinase-1 (PDK1) appears to play a central regulatory role in many cell signalings between phosphoinositide-3 kinase and various intracellular serine/threonine kinases. In resting cells, PDK1 is known to be constitutively active and is further activated by tyrosine phosphorylation (Tyr(9) and Tyr(373/376)) following the treatment of the cell with insulin or pervanadate. However, little is known about the mechanisms for this additional activation of PDK1. Here, we report that the SH2 domain of Src, Crk, and GAP recognized tyrosine-phosphorylated PDK1 in vitro. Destabilization of PDK1 induced by geldanamycin (a Hsp90 inhibitor) was partially blocked in HEK 293 cells expressing PDK1-Y9F. Co-expression of Hsp90 enhanced PDK1-Src complex formation and led to further increased PDK1 activity toward PKB and SGK. Immunohistochemical analysis with anti-phospho-Tyr(9) antibodies showed that the level of Tyr(9) phosphorylation was markedly increased in tumor samples compared with normal. Taken together, these data suggest that phosphorylation of PDK1 on Tyr(9), distinct from Tyr(373/376), is important for PDK1/Src complex formation, leading to PDK1 activation. Furthermore, Tyr(9) phosphorylation is critical for the stabilization of both PDK1 and the PDK1/Src complex via Hsp90-mediated protection of PDK1 degradation. 相似文献