Projects


Databases and Tools
Potato ESTs in CR-EST database.
FLAREX - the array experiment database at the IPK.
POCI Annotation - this is a tool to look up all available annotation for the POCI chip

Tasks
I Comparative analysis of meristem transition
II Analysis of axillary meristem initiation and outgrowth
III Functional analysis of candidate genes
IV Comparative data analysis and establishment of specific databases




I Comparative analysis of meristem transition

In work package 1 we will apply the knowledge derived from the model plant Arabidopsis to plants of the Solanaceous family. In addition, we will perform a comparative RNA profiling analysis between vegetative meristems, inflorescence meristems, flower primordia and tuber meristems, to define similarities in the expression profiles indicative of common target genes involved at integration both the flowering and tuberization inductive stimulus. Genes with an expression pattern specific of each meristem will be also identified since they are likely to play a role in flower or tuber meristem identity.

Task 1.1. Comparative analysis of meristem organization and function between Arabidopsis and Solanaceae
As mentioned above, an extensive regulatory network of transcription factors and signalling components has been found to control the function of Arabidopsis aerial meristems. Genes involved in meristem maintenance (CLV1, CLV2, CLV3, WUS), meristematic identity (STM, KNAT1, KNAT2), organ initiation (CUC1, CUC2, ANT), and organ identity (LFY) have been identified in Arabidopsis and other plant species. These genes are expressed only in specific subdomains of the meristem, which reflects the different domain functions, thus being suitable to be used as markers to analyse meristem structure and function. Genes involved in meristem maintenance, for example, are down regulated when the floral meristem terminates, with this down-regulation being a clear indicative of meristem determination. Since many of these regulatory components were shown to be highly conserved throughout the angiosperms, we will apply the knowledge derived from Arabidopsis to potato and tomato. Use of the Arabidopsis marker genes will facilitate the identification of specific structural differences characteristic of the different Solanaceae meristems. We will for example investigate specific changes in the size of specific subdomains of the meristem during transition from stolon to tuber meristem, which can be informative of changes in meristem organization at transition. Two approaches will be used: - We will directly introduce the stem cell promoters of Arabidopsis driving GFP expression in potato and tomato. In Arabidopsis these promoters drive GFP expression in: the central meristem (CLV3), the basal part of the central meristem (WUS), the meristem periphery (UFO), the organ boundaries (STM) and the epidermal (L1) layer. Several Arabidopsis promoters retain their activity when transferred to tobacco, and it is therefore of interest to test whether this holds true for these meristem-specific promoters as well. - If expression of these genes is not conserved, the corresponding promoters will be isolated from tomato and potato and new constructs will be made. - The patterns of promoter expression will be confirmed by comparing the spatial patterns of GFP fluorescence with in situ hybridizations with the corresponding gene specific probes. - The tomato or potato homologues of these genes will be isolated and used to obtain over-expression and RNAi constructs suitable to gene function analysis.

Task 1.2. RNA expression profiling of floral transition meristems
RNA profiles of SAM and floral meristems of tomato will be analysed at different stages of development, including earlier stages of apical meristem dome formation, to later stages in which flower primordia differentiation started. Transcriptional profiles will be analyzed in these cell using commercial tomato microarrays. Results obtained from these studies, will provide data for comparative analysis to tuber transition meristems, and in addition will provide an estimate on the extent of meristem-cell specific gene representation in commercial microarrays (these are expected to be under-represented because of the small size of meristems in comparison to the whole plant body). These results will be used to establish whether generation of custom-made cDNA arrays representative of SAM, non-induced stolon and floral transition meristems is required, with normalized cDNA libraries and dedicated microarrays then obtained as indicated in task 1.3.1 Natural diversity will be exploited by performing transcriptomic analysis of tomato flowering mutants such as falsiflora (produced by a mutation in the LFY ortholog FA gene) or anantha, blocked respectively in transition to inflorescence and floral organ formation, and thus are suitable to be used as source of vegetative and floral primordia meristems. Expression profiles will be compared to those of tuber transition meristems (task 1.3), and candidate genes with expression patterns compatible with a function in floral transition characterized in detail by RT-PCR and in-situ hybridisation analyses.

Task 1.3. RNA expression profiling of tuber transition meristems.
Andigena ssp. potatoes are an excellent model system to study stolon to tuber transition because of their strictly dependendance on photoperiod for tuberization. These species can be induced to tuberize by exposure to short days, with synchronous tuber formation observed after 2-3 weeks of transferring the plants to SD inductive conditions. Short days (long nights) are also absolutely required for induction, with the inductive effect of long nights being reversed by a 5 min pulse of light in the middle of the night. This strict daylength regulation allows having sets of plants induced/non-induced for tuberization with the only difference in their growth conditions being the 5 min night break. This wild-type potato variety will be used in expression profiling analysis aimed to define the changes in developmental expression profile associated with early stages of tuber transition.

Task 1.3.1 Generation of stolon transition normalized libraries and preparation of stolon specific arrays.
Commercially available potato microarray consists of 10.000 non-redundant cDNA clones from the TIGR Potato Gene Index and represents cDNAs from leaf, stolon, root, dormant tubers, sprouting eyes and microtubers, and cDNAs from Phytophtora infected leaves. Genes controlling tuber transition are likely to be strongly under-represented on this chip, with these arrays then not being suitable for RNA profiling analysis of stolon meristems. To assay this, SAMs obtained from non-induced underground stolons and up-ward stolons (that behave as vegetative shoots and produce leaf primordia) will be used in transcriptomic analysis on these chips. Arabidopsis meristem specific promoters fused to GFP will be used as visual markers to facilitate the identification and isolation of meristematic cells, with these results being both informative on the identity of the genes responsible to prevent normal leaf primordia development in the dark or to activate leaf development in aerial stolons, and also to which extent meristem-specific genes are represented in the commercial potato array. If poor hybridising spots corresponding to meristem specific genes are obtained in these studies, normalized cDNA libraries will be prepared from stolon transition meristems and used to produce dedicated meristem specific arrays. These libraries will be generated by growing andigena ssp. potatoes under SD (inductive) and SD+NB (non-inductive) conditions and harvesting the stolons at different times of induction (3, 6, 9, 14 and 20 days). RNAs will be obtained from these stolons, pooled together and used to obtain cDNA libraries enriched in stolon specific genes, by cDNA subtraction of lateral shoots. Subsequently, these libraries will be normalized by self-subtraction, and subjected to random sequencing to generate stolon specific ESTs that will be integrated in the database already available at the IPK in Gatersleben. About 3.000-5.000 unique stolon to tuber transitions ESTs are expected to be generated, and incorporated into the custom-made meristem microarray produced in this proposal.

Task 1.3.2 Transcript profiling analysis of tuber transition meristems
Andigena ssp. potatoes will be grown under SD (inductive) and SD+NB (non-inductive) conditions and RNA profiles analyzed at different stages of tuber induction, from earlier stages in which differences are still not visible, to later stages where tuber growth is clearly observed. Commercial or custom-made potato microarrays will be hybridized to these RNAs to obtain a time course profile analysis of the inductive process. Transgenic lines with altered day length regulation of the tuberization process (i.e. antisense PHYB lines which undergo also transition under SD+NB conditions or potato AtCO over-expressers with strongly delayed SD transition) will be used as well in profiling analysis to determine alterations in gene expression in these mutants associated with their tuberization phenotype. Expression profiles will be compared to those of floral transition meristems, to define similarities/differences between these two meristem transitions, indicative of common regulatory networks.

Task 1.3.3 Identification of candidate genes involved in tuberization
Genes will be grouped in clusters of similar expression profiles in order to define their association with the tuber transition or tuber fate identity processes. Genes with a candidate function in regulating these processes will be used in RT-PCR and in situ hybridization analyses to verify their pattern of accumulation and to investigate their meristem specific function. Function associated to these genes will be further investigated by over-expression or down-regulated expression using the constructs described in work package 3. Genes available in the potato database with a regulatory function compatible with a role in control of tuberization (homeodomain genes, MADS box proteins, etc) will also provide putative candidates whose possible association to tuber differentiation and growth will be assessed as before. Constructs comprised by promoter-GUS fusions of the Arabidopsis flowering-time genes FT, SOC1 and FLC (work package 3) will be transformed into potato and tomato plants to study the tissue-specific pattern of promoter expression in these heterologous plants and activation /repression of these genes during flowering or tuberization induction. Potato homologues of the Arabidopsis CO, FT and SOC1 will be isolated in silico or amplified by PCR using degenerated oligonucleotides that correspond to highly conserved regions of the protein. Tissue-specific expression of these genes will be analyzed by northern or RT-PCR analysis, and their diurnal rhythm of expression investigated in SD/LD conditions to assess a possible role in tuberization time control. These genes will subsequently be investigated by RNAi and over-expression analyses, with early/late transition, altered photoperiodic regulation, or altered tuber morphology analyzed in the transgenic lines (work package 3).

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II Analysis of axillary meristem initiation and outgrowth

Work package 2 will facilitate a comparative gene expression analysis between processes regulating initiation and outgrowth of axillary buds and potato tuber sprouting to identify genes which are either involved in both processes or determine the specificity of each of them. Since tubers are in morphological terms also stems, with shorten and broadened internodes, it is reasonable to believe that mechanisms controlling sprouting of tubers and lateral bud outgrowth are quite similar.

Task 2.1. Transcriptional control of axillary bud formation
Shoot branching is initiated by the formation of new meristems in the axils of leaf primordia. In tomato, the products of the genes Lateral suppressor (Ls) and Blind (Bl) have been shown to act as key regulators of axillary meristem initiation. The aim of this part of the project is to elucidate steps between lateral meristem initiation and bud outgrowth. These steps are regulated by genes acting downstream of Ls and Bl and may be either directly or indirectly controlled by one or both of these transcription factors. Different approaches will be applied to identify such genes.

Task 2.1.1 Transcript profiling of genotypes with different branching capacities
In the first approach we will analyze the transcription profiles of leaf axils in wildtype-, ls-, and bl-plants at different stages of development, from the earliest stages, when no differences are visible between wild-type and mutant, until the stages when bud outgrowth has already started. Transcriptional differences will be revealed by using the commercially available microarrays and custom-made cDNA arrays. Natural diversity among the species of the genus Lycopersicon will be exploited by analyzing also the transcript profiles of close relatives of tomato, e.g. Lycopersicon pennellii, which show a much higher capacity to initiate lateral shoots. Candidate genes showing promising expression profiles will be isolated and characterized in detail. Transcript accumulation of selected candidates will be analyzed by RT-PCR and RNA in-situ hybridization.

Task 2.1.2 Identifying direct targets of the meristem initiation regulators Ls and Bl
To obtain an inducible activity of the Lateral suppressor and Blind proteins, the open reading frames will be fused to the hormone binding domain of the glucocorticoid receptor and transformed into the respective mutant plants. RNA will be extracted from shoot tip material harvested at different time points after induction and used to produce probes for hybridization experiments. With this technique it will become possible to distinguish between direct target genes of Ls/Bl and genes, that are induced during later steps of lateral bud development. Promoters of direct target genes will be isolated and screened for possible conserved regulatory elements. Whole promoters or specific elements can then be used in WP3.

Task 2.1.3 Functional genetic map for branching in tomato
Candidate genes will be clustered in groups with similar expression profiles. The analysis of gene clusters, which are up- or down-regulated, may give insights into physiological changes during bud development, e.g. concerning the role of the different plant hormones. To relate specific candidate genes to functions in side-shoot development, we will screen a large population of about 200 tomato branching mutants (http://www.sgn.cornell.edu/mutants/ mutants_web/) for sequence alterations in the candidate genes. In addition, map positions of candidate genes will be determined using a collection of introgression lines developed by Eshed and Zamir (1994). The map positions will be compared with the positions of branching QTLs within the L. esculentum x L. pennellii QTL map (http://flora.nottingham.ac.uk/perl/ace/search/SolGenes). Genes that show a map position similar to branching QTLs will be further analyzed. RNAi and overexpression analysis as well as screening for interacting partners will be performed as described in work package 3.

Task 2.2. Transcriptional control of axillary bud outgrowth
The genes TEOSINTE BRANCHED1 (TB1) from maize and its Arabidopsis orthologs BRANCHED 1 and BRANCHED 2 (BRC1 and BRC2), play a key role in the control of apical dominance preventing axillary buds from growing and their down-regulation is necessary for shoot outgrowth. As function of these genes is conserved between a monocot species (maize) and a dicot (Arabidopsis) it is very likely that the Solanaceae homologues will have a similar role, being excellent candidates to control branching in tomato and bud sprouting in potato tubers.

Task 2.2.1 Isolation of TB1 orthologs from tomato and potato
We will isolate the corresponding TB1-like cDNAs from tomato and potato. Based on our experience with Arabidopsis TB1-like genes (not represented in any of the available Arabidopsis full-length cDNA collections) we consider unlikely that cDNA of these genes are present in the Solanaceae EST collections. Therefore, for tomato, the starting material will be RNA obtained from axillary buds of non-flowering plants and for potato, cDNAs will be obtained from the dormant-meristem normalized cDNA library generated in task 2.3.1.

Task 2.2.2 Control of Solanaceae bud outgrowth by TB1-like genes
The coding sequences of TB1-like genes will be used to generate inducible TB1-like RNAi lines (see work package 3) in both tomato and potato species and the effect of down-regulated expression of these genes in axillary meristem growth will be studied. If the expected phenotypes (accelerated bud outgrowth) are observed, we will proceed with tasks 2.2.3 and 2.2.4.

Task 2.2.3 Transcriptional profiling of dormant vs. sprouting buds
Down-regulation of TB1-like genes acts as a switch for bud outgrowth in Arabidopsis. The inducible RNAi transgenic lines generated in 2.2.2. will help us identifying the downstream genes of TB1-like genes and to investigate how these transcriptional changes may cause bud reactivation. We will compare the transcriptional profiles of dormant buds before and after different times of RNAi induction, RNAs isolated from buds at these different time-points will be used to synthesize cDNA probes that will be hybridized to the custom-made cDNA microarrays generated in task 2.3.1. A selection of genes up or down-regulated by TB1-like genes will be further investigated. Axillary bud expression of the selected genes will be confirmed by in situ hybridization and RNAi lines under the control of spatially restricted promoters generated as described in work package 3.

Task 2.3. Transcriptional changes during potato tuber sprouting
During the dormancy period, potato tubers undergo a sink-to-source transition. It is assumed that the regulation of meristem activity plays a key role and that re-activation of meristem function coincides with breakage of dormancy. Among others this process is under transcriptional control and is regulated by phytohormones. GAs seem to be strongly involved both tuber induction and tuber sprouting, with different approaches therefore taken to unravel the molecular mechanisms underlying regulation of these processes.

Task 2.3.1 Tuber bud-specific cDNA-libraries and generation of a "meristem-chip"
Commercially available potato microarrays are an appropriate tool to get a general overview of transcriptional changes occurring during tuber bud breakage and to identify important metabolic and signaling pathways involved. However, as for tuber induction, genes controlling sprouting might be under-represented on this chip. In order to complete the commercial chip with complementary genes specific for active and inactive tuber meristems, we intend to produce a "meristem-chip". To this end, normalized cDNA libraries from dormant and active meristematic cells of potato tuber buds will be created by following the method of self-subtraction, based on the observation that if cDNA re-annealing follows second order kinetics, rarer species anneal less rapidly and the single-stranded fraction of cDNA becomes progressively more normalized during the course of the hybridization. Starting material deriving from a field trial performed at the IPK is available and will be used for the generation of these libraries. The quality and redundancy of the libraries will be tested by random sequencing, with sequencing of about 10.000 EST's of each library aimed to identify bud-specific cDNAs. The obtained sequences will be integrated in the already available tuber-bud specific database (http://pgrc.ipk-gatersleben.de/sest_test/). Eventually, a meristem-chip containing 5000 unique EST's will be produced and used for transcriptome analysis.

Task 2.3.2 Identification of cDNA clones controlling tuber sprouting
To investigate transcriptional changes occurring in the meristematic regions of potato tubers during sink-to-source transition dormant buds and buds which just start to sprout will be isolated. Known meristem-specific promoters from Arabidopsis thaliana will be fused to reporter genes (GUS, GFP) and used as visual markers to facilitate the identification of meristematic cells and to determine the developmental state of the meristems. To monitor temporal changes of these promoter constructs we will take advantage of the rapid release of tuber dormancy observed after GA3 application. Incubation of excised buds from dormant potato tubers on filter papers soaked with 1mM GA3 allow to trigger sprouting within 4-7 days. The cDNA prepared from the different samples will be labeled with Cy3 or Cy5, respectively and hybridized to both the 10 K potato microarray (TIGR; http://www.tigr.org) and the "Meristem-chip". The analysis of the transcription profiles will lead to the identification of genes differentially expressed during tuber sprouting. To verify the results, Northern blot analysis and semi-quantitative RT-PCR will be performed with tuber material sampled at different time points during the storage period.

Task 2.3.3 Dissection of GA and KNOX -dependent and independent regulatory mechanisms
There is accumulating evidence that knotted-like homeobox genes (KNOX), which are strongly implicated in meristem function, repress expression of GA biosynthetic genes. To understand the involvement of GAs in bud breakage, transcriptional changes will be monitored in dormant and sprouting buds of tubers genetically altered in their endogenous GA-content using transgenic potato plants with increased or decreased GA-levels, respectively. The interrelationship between GA and homeobox genes, especially with the KNOX-family, will be investigated. Therefore, inducible or cell-specific promoters obtained in work package 3 will be used to drive the expression of KNOX genes in potato tubers. Transgenic plants obtained will be thoroughly characterized in terms of growth, tuberization and sprouting behavior. RNA will be isolated and corresponding cDNAs will used as probes to hybridize the arrays as described.

Task 2.3.4 Comparative analysis and identification of candidate genes to modify sprouting behavior
In order to identify the metabolic and signaling pathways involved in bud breakage the expression data accumulated in all the previously described experiments will be compared. A careful comparison of all transcript profiles should allow to elucidate the role of GAs during tuber sprouting. Furthermore, the identification of genes which are differentially expressed in tubers with either changed GA-levels or altered expression of transcription factors should unravel GA-dependent and GA-independent signaling pathways during meristem activation. The comparison of these genes with those involved in regulation of lateral bud outgrowth (task 2.1), flower (task 1.1) and tuber induction (task 1.2) will make the dissection of general and specific regulatory mechanisms possible and will give rise to the identification of a number of target genes controlling tuber sprouting.

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III Functional analysis of candidate genes

Task 3.1. Establishment of suitable expression systems
The function of key genes identified by other work packages will be assessed by analyzing the effects of their miss-expression. For that purpose, we will transfer to Solanaceae an expression system set up by partner 3 that allows inducible tissue specific gene expression. Control over the timing of miss-expression is desirable as constitutive miss-expression of essential genes could severely hinder plant development. Furthermore, distinction between direct and secondary targets becomes easier following the onset of gene expression. The restriction of gene miss-expression to a specific tissue provides an elegant way to avoid the effects of ubiquitous ectopic over-expression and allows a fine dissection of the role of a certain gene. The gene expression system developed combines the ethanol switch shown to be functional in different plant species including potato (Caddick et al. manuscript by partner 4), with specific promoters that show expression in different domains of the Arabidopsis meristem (Laufs et al., partner 3). Hence, gene expression induction can be obtained in the stem cells (CLV3 promoter), the organizing center beneath the stem cells (WUS promoter), the boundaries around organ primordia (STM promoter) and in the primordia (LFY or ANT promoter). In addition, new promoter lines will be developed in the frame of this project, using for instance the Ls promoter which is active in axillary meristems or the promoters of genes found to be activated during flower or tuber transition. These constructs will be introduced in potato and tomato and their activity used as makers to compare meristem organization between these two Solanaceous species and the plant model Arabidopsis. Selected lines allowing tissue specific gene expression will be used to establish a transformation platform to ensure inducible miss-expression of key regulatory genes.

Task 3.2. Tissue-specific RNAi using promoters characterized in 3.1.
Candidate genes controlling flowering, tuber induction or dormancy and outgrowth of axillary buds will be identified on basis of the transcriptome analysis. The functional analysis of selected genes should identify target genes for improving the agronomic performance of tomato and potato plants. Desirable achievements are an increased fruit and tuber yield by an altered biomass allocation as well as strategies to control potato tuber sprouting. Loss of function mutants are powerful tools to study gene function during plant development. In the absence of reverse genetics facilities in Solanaceae, changes in gene expression can be achieved by the well established RNAi technology. Cell-specific, non-systemic RNAi has been accomplished in potato and tobacco. Promoters described in 3.1 will be used to trigger RNAi in specific sub-domains of the plant. Also, whenever possible, dominant mutants will be created and ectopically expressed in transgenic plants. Some candidate genes may also regulate other developmental processes. For example, Mutants ls, bl, and revoluta involved in the regulation of lateral meristems are also affected in formation of inflorescences. Therefore, it is desirable to restrict transgene activity to specific tissues-, organs- or developmental stages. With that aim, specific promoters which are available for the stages of axil identity specification (Ls, CUC1), axillary meristem initiation (CET2/4), and later stages of axillary bud development (Teosinte branched/Cycloidea) will be combined with RNAi constructs of selected target genes and introduced into tomato plants. Such promoters will be used to express an ethanol-dependent transcriptional activator in specific meristem cells. In this way, prototype transgenic potato and tomato lines will be obtained, endowed with meristem cell specific expression of the ethanol-inducible transcriptional activator. A 35S minimal promoter activated by the ethanol-dependent transcriptional factor will then be used for expression of RNAi directed against the candidate genes selected in previous tasks, thus allowing inducible silencing of these genes.

Task 3.3. Tissue-specific over-expression using promoters characterized in 3.1.
In reciprocal experiments, key genes will be over-expressed in an inducible and tissue specific manner using the lines described in 3.2. This will enable to increase both the expression levels of candidate genes in their normal expression domains and to ectopically express these genes in new domains. Over-expression of the known side-shoot regulators Ls and Bl lead to pleiotropic alterations of plant development that are difficult to explain. Restricting the expression domains may overcome this problem. Candidate genes can be integrated in genetic pathways by expressing them under general or specific promoters in the branching mutant backgrounds to test for full or partial complementation of the ls or bl phenotypes. In addition, using different types of inducible promoters can help to elucidate at which time the respective gene products are needed.

Task 3.4. Establishment of Y2H-libraries and identification of protein:protein interactions
A further insight in the signaling networks responsible for the regulation of meristem activities will be gained from the characterization of meristem-specific protein:protein interactions. Candidates identified in WP 1 and 2 will be used as baits in yeast-two-hybrid screens. To this end Y2H libraries will be constructed from meristematic tissues. A GAL4 based yeast two-hybrid system will be employed, with the coding regions corresponding to the genes of interests amplified by RT-PCR, fused with the GAL4 binding domain (BD), and used as bait to screen an activation domain (AD) tagged cDNA library. As a first approach, a library specific for the axillary regions of tomato and potato will be used to screen for proteins interacting with Ls and Bl, with these screen subsequently applied to other genes of interest.

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IV Comparative data analysis and establishment of specific databases

Within Work Package 4 all sequence and transcript data obtained in work packages 1 and 2 will be compiled and comparatively analyzed. This work will be done at the IPK in Gatersleben, where a bioinformatic platform established within the frame of GABI can be engaged. The work comprises on one hand the evaluation of the sequence data obtained, the integration in an (already available) Solanaceous-database, the cluster analysis, and the comparison of the different libraries. On the other hand an overall comparative transcriptome analysis will be performed with transcript profiles from the different developmental processes such as tuber formation and sprouting, or lateral bud formation and outgrowth. In this way the underlying molecular mechanism which are specific for a certain developmental process will be determined. The comparison should also lead to the identification of general regulatory pathways controlling meristem activity and function. The accomplishment of these tasks depends on the storage off all data in well-structured and easily accessible formats.

Task 4.1. Establishment of project-relevant databases
The first task within this work package will be to evaluate the demands and potential dependencies between all partners, to design the databases accordingly. We will also collect and examine existing interfaces for potential use in this project. All data recorded and reported will comply with MIAME standards and will be stored in the ORACLE database. After data acquisition, a data model will be designed to store all information about meristem specific ESTs generated in tasks 1.3.1 and 2.3.1 and all expression profiles obtained in work package 1 and 2. In addition, externally available data from other potato and tomato sequencing initiatives will be included in the model. Tools will be developed for the data import from the different partners and for data integration. During the project new information will continuously be generated so the database will be continuously adapted to incorporate it.

Task 4.2. Comparative data analysis
Comparison of expression data will be the most demanding part of the project. To accomplish this task, we will use available existing tools, as well as tools developed within the frame of the project. The visualization of array data and their assignment to metabolic and signaling pathways are also essential tasks within this phase. Software to integrate and query the data generated in our project with information of fully sequenced plants like Arabidopsis or rice will be adapted. Using specific software tools (e.g. StackPACK™) all EST's produced within the project will be clustered, the redundancy decreased and the generation of unigene sets achieved. The results of the EST clustering can be used to assess the distributions of ESTs within or between the different libraries.

Task 4.3. Web-based information system with user authentication
The results of the project will be published on the WWW. In addition, project partners will have access to the restricted internal data. To fulfill these requirements a web portal infrastructure will be established.

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Genosome - Projects

 

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tomato
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