Seed-specific expression of seven Arabidopsis promoters.

Seeds contain storage compounds, from various carbohydrates to proteins and lipids, which are synthesized during seed development. For the purposes of many plant researches or commercial applications, developing promoter systems expressing specifically in seeds or in particular constituents or tissues/compartments of seeds are indispensable. To screen genes dominantly or specifically expressed in seed tissues, we analyzed Arabidopsis ATH1 microarray data open to the public.

Overexpression of sweetpotato expansin cDNA (IbEXP1) increases seed yield in Arabidopsis.

Results of transcriptome analyses suggest that expansin genes play an active role in seed development and yield, but gain- or loss-of-function studies have not yet elucidated the functional role(s) of the expansin gene(s) in these processes. We have overexpressed a sweetpotato expansin gene (IbEXP1) in Arabidopsis under the control of cauliflower mosaic 35S promoter in an attempt to determine the effect of the expansin gene in seed development and yield in heterologous plants. The growth rate was enhanced in IbEXP1-overexpressing (ox) plants relative to wild-type Col-0 plants during early vegetative growth stage.

Enhanced antioxidant and protective activities on retinal ganglion cells of carotenoids-overexpressing transgenic carrot.

Carotenoids are considered to act as antioxidants and protect humans from serious disorders such as skin degeneration and ageing, cardiovascular disease, certain types of cancer, and age-related diseases of the eye. In this study, these chemopreventive activities of a carotenoids-overexpressing transgenic carrot were evaluated. The results of DPPH, hydroxyl, and superoxide radical scavenging tests demonstrate that the acetone extract obtained from the taproots of the carrot plants exhibits significant antioxidant activity.

Down-regulation of the IbEXP1 gene enhanced storage root development in sweetpotato.

The role of an expansin gene (IbEXP1) in the formation of the storage root (SR) was investigated by expression pattern analysis and characterization of IbEXP1-antisense sweetpotato (Ipomoea batatas cv. Yulmi) plants in an attempt to elucidate the molecular mechanism underlying SR development in sweetpotato. The transcript level of IbEXP1 was high in the fibrous root (FR) and petiole at the FR stage, but decreased significantly at the young storage root (YSR) stage.

A sweetpotato SRD1 promoter confers strong root-, taproot-, and tuber-specific expression in Arabidopsis, carrot, and potato.

Harvestable, starch-storing organs of plants, such as fleshy taproots and tubers, are important agronomic products that are also suitable target organs for use in the molecular farming of recombinant proteins due to their strong sink strength. To exploit a promoter directing strong expression restricted to these storage organs, we isolated the promoter region (3.0 kb) of SRD1 from sweetpotato (Ipomoea batatas cv.

Production of serotonin by dual expression of tryptophan decarboxylase and tryptamine 5-hydroxylase in Escherichia coli.

A plant-specific biogenic amine, serotonin, was produced by heterologous expression of two key biosynthetic genes, tryptophan decarboxylase (TDC) and tryptamine 5-hydroxylase (T5H), in Escherichia coli. The native T5H, a cytochrome P450 enzyme, was unable to be functionally expressed in E. coli.

Transcriptional regulation of the cinnamyl alcohol dehydrogenase gene from sweet potato in response to plant developmental stage and environmental stress.

Cinnamyl alcohol dehydrogenase (CAD) is a key enzyme in the biosynthesis of lignin. We have isolated full length of a cDNA encoding CAD (IbCAD1) that was previously identified as the most abundant gene in an EST library of sweetpotato suspension cells. Phylogenetic analysis revealed that IbCAD1 belongs to the family of defense-related CADs.

SRD1 is involved in the auxin-mediated initial thickening growth of storage root by enhancing proliferation of metaxylem and cambium cells in sweetpotato (Ipomoea batatas).

A sweetpotato (Ipomoea batatas cv. 'Jinhongmi') MADS-box protein cDNA (SRD1) has been isolated from an early stage storage root cDNA library. The role of the SRD1 gene in the formation of the storage root in sweetpotato was investigated by an expression pattern analysis and characterization of SRD1-overexpressing (ox) transgenic sweetpotato plants.

The sweet potato ADP-glucose pyrophosphorylase gene (ibAGP1) promoter confers high-level expression of the GUS reporter gene in the potato tuber.

Molecular farming refers to the process of creating bioengineered plants with the capability of producing potentially valuable products, such as drugs, vaccines, and chemicals. We have investigated the potential of the sweet potato ADP-glucose pyrophosphorylase gene (ibAGP1) promoter and its transit peptide (TP) as an expression system for the mass production of foreign proteins in potato. The ibAGP1 promoter and its TP sequence were transformed into potato along with beta-glucuronidase (GUS) as a reporter gene, and GUS activity was subsequently analyzed in the transgenic potato plants.

Expression of serotonin derivative synthetic genes on a single self-processing polypeptide and the production of serotonin derivatives in microbes.

The plant-specific serotonin derivatives feruloylserotonin (FS) and 4-coumaroylserotonin (CS) are synthesized by the enzymes 4-coumarate:coenzyme A ligase (4CL) and serotonin N-hydroxycinnamoyltransferase (SHT). To express these genes coordinately, SHT was fused in-frame with the self-processing FDMV 2A sequence followed by 4CL in a single open reading frame and introduced into Escherichia coli or Saccharomyces cerevisiae. The transgenes were abundantly expressed in both recombinant microbes, but functional expression was achieved only in yeast, with cleavage at the 2A sequence yielding monomeric SHT-2A and 4CL as judged by immunoblot and product analyses.

Dissected effect of a transit peptide of the ADP-glucose pyrophosphorylase gene from sweetpotato (ibAGP2) in increasing foreign protein accumulation.

The transit peptide sequence of ibAGP2 (TP2) was found to be capable of targeting protein into the chloroplast in the Arabidopsis protoplasts. TP2 was fused to a beta-glucuronidase (GUS) reporter gene and expressed in Arabidopsis under the control of the ibAGP2 promoter with the aim of dissecting the effect of the transit peptide in elevating foreign protein accumulation in the transgenic plant. beta-glucuronidase protein levels were determined at three different developmental stages and in assorted tissues.

A sepal-expressed ADP-glucose pyrophosphorylase gene (NtAGP) is required for petal expansion growth in 'Xanthi' tobacco.

In this study, a tobacco (Nicotiana tabacum 'Xanthi') ADP-glucose pyrophosphorylase cDNA (NtAGP) was isolated from a flower bud cDNA library and the role of NtAGP in the growth of the floral organ was characterized. The expression of NtAGP was high in the sepal, moderate in the carpel and stamen, and low in the petal tissues. NtAGP-antisense plants produced flowers with abnormal petal limbs due to the early termination of the expansion growth of the petal limbs between the corolla lobes.

A strong constitutive gene expression system derived from ibAGP1 promoter and its transit peptide.

To develop a strong constitutive gene expression system, the activities of ibAGP1 promoter and its transit peptide were investigated using transgenic Arabidopsis and a GUS reporter gene. The ibAGP1 promoter directed GUS expression in almost entire tissues including rosette leaf, inflorescence stem, inflorescence, cauline leaf and root, suggesting that the ibAGP1 promoter is a constitutive promoter. GUS expression mediated by ibAGP1 promoter was weaker than that by CaMV35S promoter in all tissue types, but when GUS protein was targeted to plastids with the aid of the ibAGP1 transit peptide, GUS levels increased to higher levels in lamina, petiole and cauline leaf compared to those produced by CaMV35S promoter.

Cloning and functional expression of the gene encoding an inhibitor against Aspergillus flavus alpha-amylase, a novel seed lectin from Lablab purpureus (Dolichos lablab).

Maize is one of the more important agricultural crops in the world and, under certain conditions, prone to attack from pathogenic fungi. One of these, Aspergillus flavus, produces toxic and carcinogenic metabolites, called aflatoxins, as byproducts of its infection of maize kernels. The alpha-amylase of A.

Proteome analysis of gametophores identified a metallothionein involved in various abiotic stress responses in Physcomitrella patens.

Physcomitrella patens is a model plant for studying gene function using a knockout strategy. To establish a proteome database for P. patens, we resolved over 1,500 soluble proteins from gametophore and protonema tissues by two-dimensional electrophoresis (2-DE) and obtained peptide mass fingerprints (PMFs) by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS).

Two sweetpotato ADP-glucose pyrophosphorylase isoforms are regulated antagonistically in response to sucrose content in storage roots.

The transcriptional regulation of ADP-glucose pyrophosphorylase (AGPase) genes in detached leaves in response to exogenous sucrose has been investigated earlier; however the effects of endogenous sucrose on AGPase gene transcription in leaves or starch-accumulating tissues have not yet been determined. We therefore have investigated the relationship between endogenous sucrose content in the storage tissues of sweetpotato (Ipomoea batatas cv. Yulmi) and the rate of transcription of the two sweetpotato AGPase isoforms, ibAGP1 and ibAGP2, by means of transient expression analysis of their promoters.

Evidence for interaction between the 2a polymerase protein and the 3a movement protein of Cucumber mosaic virus.

The genome of Cucumber mosaic virus consists of three single-stranded RNA molecules, RNAs 1, 2 and 3. RNAs 1 and 2 encode the 1a and 2a proteins, respectively, which are necessary for replication of the viral genome and have been implicated in movement of the viral RNAs in plants. The 3a movement protein (MP), encoded by RNA 3, is essential for transferring the RNA genomes from infected cells to adjacent cells across the plasmodesmata.

Novel CIPK1-associated proteins in Arabidopsis contain an evolutionarily conserved C-terminal region that mediates nuclear localization.

Environmental stimuli, including light, pathogens, hormones, and abiotic stresses, elicit changes in the cytosolic Ca(2+) signatures of plant cells. However, little is known about the molecular mechanisms by which plants sense and transmit the specific cytoplasmic Ca(2+) signal into the nucleus, where gene regulation occurs to respond appropriately to the stress. In this study, we have identified two novel Arabidopsis (Arabidopsis thaliana) proteins specifically associated with Calcineurin B-Like-Interacting Protein Kinase1 (CIPK1), a member of Ser/Thr protein kinases that interact with the calcineurin B-like Ca(2+)-binding proteins.

Overexpression of human erythropoietin (EPO) affects plant morphologies: retarded vegetative growth in tobacco and male sterility in tobacco and Arabidopsis.

Erythropoietin (EPO) is a glycoprotein used for curing human anemia by regulating the differentiation of erythroid progenitors and the production of red blood cells. To examine the expression of recombinant EPO in plants, pPEV-EP21, in which human epo cDNA under the control of the CaMV 35S promoter, was introduced into tobacco and Arabidopsis via Agrobacterium tumefaciens-mediated transformation. The RNA expression level of epo in the transgenic lines was initially estimated by Northern blot analysis.

Genomic organizations of two small subunit ADP-glucose pyrophosphorylase genes from sweetpotato.

The genomic features of the small subunit ADP-glucose pyrophosphorylase (AGPase) isoforms are different in barley and maize. The two isoforms found in barley originated from one single gene through alternative splicing, while two independent genes encode the two isoforms in maize. To ascertain the genomic organizations of two small subunit AGPase isoforms in sweetpotato (ibAGP1 and ibAGP2), we isolated genomic DNAs containing the entire coding regions of two genes.

Characterization of the plastid-encoded carboxyltransferase subunit (accD) gene of potato.

The plastid accD gene encoding the carboxyltransferase b subunit of acetyl-coenzyme A carboxylase (ACCase) was cloned from potato. Potato accD (saccD) is 2487 bp in length with a 614 bp 5 cent upstream promoter region and an ORF of 1524 bp, corresponding to a polypeptide of 507 amino acids. The N-terminal region lacks recognizable motifs, while the C-terminal regions contains five motifs.

Comparative analysis of expressed sequence tags from Sesamum indicum and Arabidopsis thaliana developing seeds.

Sesame (Sesamum indicum) is an important oilseed crop which produces seeds with 50% oil that have a distinct flavor and contains antioxidant lignans. Because sesame lignans are known to have antioxidant and health-protecting properties, metabolic pathways for lignans have been of interest in developing sesame seeds. As an initial approach to identify genes involved in accumulation of storage products and in the biosynthesis of antioxidant lignans, 3328 expressed sequence tags (ESTs) were obtained from a cDNA library of immature seeds 5-25 days old.

Identification of genes possibly related to storage root induction in sweet potato.

To identify genes related to initiation of storage root development in sweet potato, a cDNA library was constructed with early stage storage roots (0.3-1 cm in diameter). Single-pass sequences of the 5' ends of 2859 sweet potato cDNA clones were assembled into 483 clusters and 442 singletons.

Diversity and varietal classification of Hibiscus syriacus L. with the heterogeneity within retrotransposon-like elements.

Retrotransposons are present in multi-copy numbers that are integrated into plant genomes with considerable heterogeneous sequences within a single plant and between plant species, which allows the use of retrotransposons as additional sources of DNA polymorphism. A primer design for the sequence-tagged specific site and cleaved amplified polymorphic sequences (STS-CAPs) that are derived from retrotransposon-like sequences was developed for the molecular marker analysis in Hibiscus syriacus. This method was applied for the detection of sequence variations of intact retrotransposons that exist in plant genomes, which resulted in higher polymorphisms than in the amplified fragment length polymorphism (AFLP).