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Natasha V. Raikhel

Bio: Natasha V. Raikhel is an academic researcher from University of California, Riverside. The author has contributed to research in topics: Arabidopsis & Vacuole. The author has an hindex of 78, co-authored 218 publications receiving 18121 citations. Previous affiliations of Natasha V. Raikhel include National Academy of Sciences & University of California, Berkeley.


Papers
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Journal ArticleDOI
TL;DR: The more than 13,400 plant ESTs that are currently available provide a new resource that will facilitate progress in many areas of plant biology and are illustrated by a description of the results obtained from analysis of 1500 Arabidopsis ESTs from a cDNA library prepared from equal portions of poly(A+) mRNA from etiolated seedlings, roots, leaves, and flowering inflorescence.
Abstract: High-throughput automated partial sequencing of anonymous cDNA clones provides a method to survey the repertoire of expressed genes from an organism. Comparison of the coding capacity of these expressed sequence tags (ESTs) with the sequences in the public data bases results in assignment of putative function to a significant proportion of the ESTs. Thus, the more than 13,400 plant ESTs that are currently available provide a new resource that will facilitate progress in many areas of plant biology. These opportunities are illustrated by a description of the results obtained from analysis of 1500 Arabidopsis ESTs from a cDNA library prepared from equal portions of poly(A+) mRNA from etiolated seedlings, roots, leaves, and flowering inflorescences. More than 900 different sequences were represented, 32% of which showed significant nucleotide or deduced amino acid sequence similarity to previously characterized genes or proteins from a wide range of organisms. At least 165 of the clones had significant deduced amino acid sequence homology to proteins or gene products that have not been previously characterized from higher plants. A summary of methods for accessing the information and materials generated by the Arabidopsis cDNA sequencing projects is provided.

740 citations

Journal ArticleDOI
TL;DR: It is demonstrated that two homologous, 5-kD cysteine-rich proteins designated Raphanus sativus-antifungal protein 1 and Rs-AFP2 are located in the cell wall and occur predominantly in the outer cell layers lining different seed organs, and are preferentially released during seed germination after disruption of the seed coat.
Abstract: Radish seeds have previously been shown to contain two homologous, 5-kD cysteine-rich proteins designated Raphanus sativus-antifungal protein 1 (Rs-AFP1) and Rs-AFP2, both of which exhibit potent antifungal activity in vitro. We now demonstrate that these proteins are located in the cell wall and occur predominantly in the outer cell layers lining different seed organs. Moreover, Rs-AFPs are preferentially released during seed germination after disruption of the seed coat. The amount of released proteins is sufficient to create a microenvironment around the seed in which fungal growth is suppressed. Both the cDNAs and the intron-containing genomic regions encoding the Rs-AFP preproteins were cloned. Transcripts (0.55 kb) hybridizing with an Rs-AFP1 cDNA-derived probe were present in near-mature and mature seeds. Such transcripts as well as the corresponding proteins were barely detectable in healthy uninfected leaves but accumulated systemically at high levels after localized fungal infection. The induced leaf proteins (designated Rs-AFP3 and Rs-AFP4) were purified and shown to be homologous to seed Rs-AFPs and to exert similar antifungal activity in vitro. A chimeric Rs-AFP2 gene under the control of the constitutive cauliflower mosaic virus 35S promoter conferred enhanced resistance to the foliar pathogen Alternaria longipes in transgenic tobacco. The term "plant defensins" is proposed to denote these defense-related proteins.

713 citations

Journal ArticleDOI
TL;DR: Evidence is presented of four tonoplast-localized soluble N-ethylmaleimide–sensitive factor attachment protein receptors (SNAREs), representing each of the four groups of SNARE proteins necessary for membrane fusion in Arabidopsis thaliana.
Abstract: Vacuoles play central roles in plant growth, development, and stress responses. To better understand vacuole function and biogenesis we have characterized the vegetative vacuolar proteome from Arabidopsis thaliana. Vacuoles were isolated from protoplasts derived from rosette leaf tissue. Total purified vacuolar proteins were then subjected either to multidimensional liquid chromatography/tandem mass spectrometry or to one-dimensional SDS-PAGE coupled with nano-liquid chromatography/tandem mass spectrometry (nano-LC MS/MS). To ensure maximum coverage of the proteome, a tonoplast-enriched fraction was also analyzed separately by one-dimensional SDS-PAGE followed by nano-LC MS/MS. Cumulatively, 402 proteins were identified. The sensitivity of our analyses is indicated by the high coverage of membrane proteins. Eleven of the twelve known vacuolar-ATPase subunits were identified. Here, we present evidence of four tonoplast-localized soluble N-ethylmaleimide–sensitive factor attachment protein receptors (SNAREs), representing each of the four groups of SNARE proteins necessary for membrane fusion. In addition, potential cargo of the N- and C-terminal propeptide sorting pathways, association of the vacuole with the cytoskeleton, and the vacuolar localization of 89 proteins of unknown function are identified. A detailed analysis of these proteins and their roles in vacuole function and biogenesis is presented.

617 citations

Journal ArticleDOI
TL;DR: Lectins are carbohydrate-binding proteins that bind glycoproteins, glycolipids, or polysaccharides with high affinity and have the capability to serve as recognition molecules within a cell, between cells, or be?
Abstract: Lectins are carbohydrate-binding proteins that bind gly? cans of glycoproteins, glycolipids, or polysaccharides with high affinity (Goldstein and Hayes, 1978). Because of their binding specificity, they have the capability to serve as recognition molecules within a cell, between cells, or be? tween organisms. It is assumed that lectins play fundamental biological roles in plants because they are found in many different species and in many different organs and tissues.

608 citations

Journal ArticleDOI
25 Apr 2013-Cell
TL;DR: It is shown that the translation inhibition, but not the mRNA cleavage activity, of Arabidopsis miRNAs requires ALTERED MERISTEM PROGRAM1 (AMP1), and AMP1-independent recruitment of miRNA target transcripts to membrane fractions shows that mi RNAs inhibit the translation of target RNAs on the ER.

444 citations


Cited by
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Journal ArticleDOI
20 Oct 1995-Science
TL;DR: A high-capacity system was developed to monitor the expression of many genes in parallel by means of simultaneous, two-color fluorescence hybridization, which enabled detection of rare transcripts in probe mixtures derived from 2 micrograms of total cellular messenger RNA.
Abstract: A high-capacity system was developed to monitor the expression of many genes in parallel. Microarrays prepared by high-speed robotic printing of complementary DNAs on glass were used for quantitative expression measurements of the corresponding genes. Because of the small format and high density of the arrays, hybridization volumes of 2 microliters could be used that enabled detection of rare transcripts in probe mixtures derived from 2 micrograms of total cellular messenger RNA. Differential expression measurements of 45 Arabidopsis genes were made by means of simultaneous, two-color fluorescence hybridization.

10,287 citations

Journal ArticleDOI
14 Dec 2000-Nature
TL;DR: This is the first complete genome sequence of a plant and provides the foundations for more comprehensive comparison of conserved processes in all eukaryotes, identifying a wide range of plant-specific gene functions and establishing rapid systematic ways to identify genes for crop improvement.
Abstract: The flowering plant Arabidopsis thaliana is an important model system for identifying genes and determining their functions. Here we report the analysis of the genomic sequence of Arabidopsis. The sequenced regions cover 115.4 megabases of the 125-megabase genome and extend into centromeric regions. The evolution of Arabidopsis involved a whole-genome duplication, followed by subsequent gene loss and extensive local gene duplications, giving rise to a dynamic genome enriched by lateral gene transfer from a cyanobacterial-like ancestor of the plastid. The genome contains 25,498 genes encoding proteins from 11,000 families, similar to the functional diversity of Drosophila and Caenorhabditis elegans--the other sequenced multicellular eukaryotes. Arabidopsis has many families of new proteins but also lacks several common protein families, indicating that the sets of common proteins have undergone differential expansion and contraction in the three multicellular eukaryotes. This is the first complete genome sequence of a plant and provides the foundations for more comprehensive comparison of conserved processes in all eukaryotes, identifying a wide range of plant-specific gene functions and establishing rapid systematic ways to identify genes for crop improvement.

8,742 citations

01 Aug 2000
TL;DR: Assessment of medical technology in the context of commercialization with Bioentrepreneur course, which addresses many issues unique to biomedical products.
Abstract: BIOE 402. Medical Technology Assessment. 2 or 3 hours. Bioentrepreneur course. Assessment of medical technology in the context of commercialization. Objectives, competition, market share, funding, pricing, manufacturing, growth, and intellectual property; many issues unique to biomedical products. Course Information: 2 undergraduate hours. 3 graduate hours. Prerequisite(s): Junior standing or above and consent of the instructor.

4,833 citations

Journal ArticleDOI
TL;DR: Limiting discussion to stress-induced phenylpropanoids eliminates few of the structural classes, because many compounds that are constitutive in one plant species or tissue can be induced by various stresses in another species or in another tissue of the same plant.
Abstract: Phenylpropanoid compounds encompass a wide range of structural classes and biological functions. Limiting discussion to stress-induced phenylpropanoids eliminates few of the structural classes, because many compounds thst are constitutive in one plant species or tissue can be induced by various stresses in another species or in another tissue of the same plant (Beggs et al., 1987; Christie et al., 1994).

4,046 citations

Journal ArticleDOI
Gerald A. Tuskan1, Gerald A. Tuskan2, Stephen P. DiFazio3, Stephen P. DiFazio1, Stefan Jansson4, Joerg Bohlmann5, Igor V. Grigoriev6, Uffe Hellsten6, Nicholas H. Putnam6, Steven G. Ralph5, Stephane Rombauts7, Asaf Salamov6, Jacquie Schein, Lieven Sterck7, Andrea Aerts6, Rishikeshi Bhalerao4, Rishikesh P. Bhalerao8, Damien Blaudez9, Wout Boerjan7, Annick Brun9, Amy M. Brunner10, Victor Busov11, Malcolm M. Campbell12, John E. Carlson13, Michel Chalot9, Jarrod Chapman6, G.-L. Chen1, Dawn Cooper5, Pedro M. Coutinho14, Jérémy Couturier9, Sarah F. Covert15, Quentin C. B. Cronk5, R. Cunningham1, John M. Davis16, Sven Degroeve7, Annabelle Déjardin9, Claude W. dePamphilis13, John C. Detter6, Bill Dirks17, Inna Dubchak18, Inna Dubchak6, Sébastien Duplessis9, Jürgen Ehlting5, Brian E. Ellis5, Karla C Gendler19, David Goodstein6, Michael Gribskov20, Jane Grimwood21, Andrew Groover22, Lee E. Gunter1, Björn Hamberger5, Berthold Heinze, Yrjö Helariutta23, Yrjö Helariutta8, Yrjö Helariutta24, Bernard Henrissat14, D. Holligan15, Robert A. Holt, Wenyu Huang6, N. Islam-Faridi22, Steven J.M. Jones, M. Jones-Rhoades25, Richard A. Jorgensen19, Chandrashekhar P. Joshi11, Jaakko Kangasjärvi23, Jan Karlsson4, Colin T. Kelleher5, Robert Kirkpatrick, Matias Kirst16, Annegret Kohler9, Udaya C. Kalluri1, Frank W. Larimer1, Jim Leebens-Mack15, Jean-Charles Leplé9, Philip F. LoCascio1, Y. Lou6, Susan Lucas6, Francis Martin9, Barbara Montanini9, Carolyn A. Napoli19, David R. Nelson26, C D Nelson22, Kaisa Nieminen23, Ove Nilsson8, V. Pereda9, Gary F. Peter16, Ryan N. Philippe5, Gilles Pilate9, Alexander Poliakov18, J. Razumovskaya1, Paul G. Richardson6, Cécile Rinaldi9, Kermit Ritland5, Pierre Rouzé7, D. Ryaboy18, Jeremy Schmutz21, J. Schrader27, Bo Segerman4, H. Shin, Asim Siddiqui, Fredrik Sterky, Astrid Terry6, Chung-Jui Tsai11, Edward C. Uberbacher1, Per Unneberg, Jorma Vahala23, Kerr Wall13, Susan R. Wessler15, Guojun Yang15, T. Yin1, Carl J. Douglas5, Marco A. Marra, Göran Sandberg8, Y. Van de Peer7, Daniel S. Rokhsar6, Daniel S. Rokhsar17 
15 Sep 2006-Science
TL;DR: The draft genome of the black cottonwood tree, Populus trichocarpa, has been reported in this paper, with more than 45,000 putative protein-coding genes identified.
Abstract: We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport.

4,025 citations