To understand the molecular defense mechanism controlling the hypersensitive response (HR) better, we examined the hot pepper plant (Capsicum annuum L. cv. Bugang), which exhibits an HR in response to infection by Tobacco mosaic virus pathotype P0 (TMV-P0). A full-length cDNA clone was isolated by differential screening of a cDNA library that was constructed with mRNA extracted from hot pepper leaves during the resistance response to TMV-P0. The predicted amino acid sequence of the cDNA clone exhibited a high sequence similarity to germin-like protein (GLP). The CaGLP1 (Capsicum annuum GLP1) cDNA contains a single open reading frame of 660 bp encoding 220 amino acid residues. Upon inoculation with TMV or Xanthomonas, CaGLP1 transcripts were specifically accumulated in the incompatible interaction but not in the compatible interaction. In plants treated with salicylic acid (SA) or ethephon, which are signal molecules in the defense-related signal transduction pathway, CaGLP1 transcripts were accumulated rapidly. As far as we know, this is the first report that plant GLPs can be specifically induced during a defense response against viral infection. These data suggest that in the hot pepper plant CaGLP1 may be involved in the defense response to viral pathogens, and thus be classified as a new family of PR proteins, 'PR-16'.

In many plants, including hot pepper plants, productivity is greatly affected by pathogen attack. We reported previously that tobacco stress-induced gene 1 (Tsi1) may play an important role in regulating stress responsive genes and pathogenesis-related (PR) genes. In this study, we demonstrated that overexpression of Tsi1 gene in transgenic hot pepper plants induced constitutive expression of several PR genes in the absence of stress or pathogen treatment. The transgenic hot pepper plants expressing Tsi1 exhibited resistance to Pepper mild mottle virus (PMMV) and Cucumber mosaic virus (CMV). Furthermore, these transgenic plants showed increased resistance to a bacterial pathogen, Xanthomonas campestris pv. vesicatoria and also an oomycete pathogen, Phytophthora capsici. These results suggested that ectopic expression of Tsi1 in transgenic hot pepper plants enhanced the resistance of the plants to various pathogens, including viruses, bacteria, and oomycete. These results suggest that using transcriptional regulatory protein genes may contribute to developing broad-spectrum resistance in crop plants.

Acetylcholinesterase (AChE) is an extremely critical hydrolase tightly associated with neurological diseases. Currently, specific substrates available for imaging AChE activity still remain a great challenge due to the interference from...

A fluorescent molecular probe for the identification of glioblastoma is developed. The probe allows the tracing of the cysteine (Cys) level, which is recognized as a new biomarker of GBM.

Capsicum annuum tobacco mosaic virus (TMV)-induced clone 1 (CaTin1) gene was expressed early during incompatible interaction of hot pepper (Caspsicum annuum) plants with TMV and Xanthomonas campestris. RNA-blot analysis showed that CaTin1 gene was expressed only in roots in untreated plants and induced mainly in leaf in response to ethylene, NaCl, and methyl viologen but not by salicylic acid and methyl jasmonate. The ethylene dependence of CaTin1 induction upon TMV inoculation was demonstrated by the decrease of CaTin1 expression in response to several inhibitors of ethylene biosynthesis or its action. Transgenic tobacco (Nicotiana tabacum) plants expressing CaTin1 gene in sense-or antisense-orientation showed interesting characteristics such as the accelerated growth and the enhanced resistance to biotic as well as abiotic stresses. Such characteristics appear to be caused by the elevated level of ethylene and H 2 O 2 . Moreover, in transgenic plants expressing antisense CaTin1 gene, the expression of some pathogenesis-related genes was enhanced constitutively, which may be mainly due to the increased ethylene level. The promoter of CaTin1 has four GCC-boxes, two AT-rich regions, and an elicitor-inducible W-box. The induction of the promoter activity by ethylene depends on GCC-boxes and by TMV on W-box. Taken together, we propose that the CaTin1 up-regulation or down-regulation interferes with the redox balance of plants leading to the altered response to ethylene and biotic as well as abiotic stresses.Multiple preformed antimicrobial compounds contribute to the constitutive defense machinery of plants against pathogenic organisms. In addition, plants can trigger the inducible defense programs upon the perception of invaders. The early signaling molecules leading to R-gene-mediated resistance are ion fluxes, GTP-binding proteins, protein kinases, phosphatases, and phospholipases (Hammond-Kosack and Jones, 1996). Plants also respond to external stimuli such as microbial elicitors of cell death and/or defense responses by changing the calcium influx of the cell (Ebel and Scheel, 1997;Higgins et al., 1998). The increase of cytosolic calcium leads to cell death, which seems necessary for hypersensitive cell death triggered by rust fungi (Xu and Heath, 1998). The calcium channel blocker La 31 , on the other hand, prevents the bacteriainduced hypersensitive response (HR) in soybean (Glycine max) leaves (Levine et al., 1996). The burst in the oxidative metabolism generated within minutes of infection leads to the accumulation of the reactive oxygen intermediates (ROI) such as H 2 O 2 and superoxide anion (O 2 d 2 ), involving NADPH-dependent oxidase. ROI serve as signaling molecules, for example in the recognition of the attack by fungal pathogens (Lamb and Dixon, 1997).Ethylene is widely known to modulate the organ senescence induced by various stress factors such as plant pathogens (Moore et al., 2000), O 3 2 (Pell et al., 1997), and hypoxia (He et al., 1996). O 3 2 induces genes involved in the ethylene biosynthes...

Recently reported two-photon fluorescent probes based on a functionalized dipolar naphthalene platform (FDNP) are summarized.

Hot pepper (Capsicum annuum L. cv. Bugang) plants exhibit a hypersensitive response (HR) upon infection by Tobacco mosaic virus (TMV) pathotype P0. To elucidate molecular mechanism that underlies this resistance, hot pepper cv. Bugang leaves were inoculated with TMV-P0 and genes specifically up-regulated during the HR were isolated by differential screening. One of the clones, CaAlaAT1 encoding a putative alanine aminotransferase (EC 2.6.1.2) exhibited organ-specific expression pattern and the transcript accumulated abundantly in red (ripe) fruit tissues. CaAlaAT1 transcript was also induced in older leaves during senescence. The expression of CaAlaAT1 gene was increased in the incompatible interaction with TMV-P0 but was not in the compatible interaction with TMV-P1.2. When a strain of Xanthomonas campestris pv. vesicatoria (Xcv) carrying an AvrBs2 gene was infiltrated into the leaves of a pepper cv. ECW 20R carrying Bs2 resistance gene, a marked induction and maintenance of CaAlaAT1 gene expression was observed. The expression of CaAlaAT1 gene was triggered by salicylic acid (SA) and ethylene but not by methyl jasmonate (MeJA). CaAlaAT1 seemed to be localized mostly at the cytosol from the polyethylene glycol (PEG)-mediated transformation experiment. CaAlaAT1 seemed to catalyze alanine: 2-oxoglutarate aminotransferase (AKT) reaction, which was a main activity among the four activities in vitro, during the resistance response against TMV in hot pepper. These results suggest that CaAlaAT1, a protein known to be involved in metabolic reactions, might be one of the components in the plant's defense signal pathway against pathogens.

We report, for the first time, a new red-emitting hybrid material based on a single-benzene-based fluorophore (SBBF) and silica. This robust formulation shows several features, including bright emissions at a red wavelength (>600 nm), high scalability (>gram-scale), facile synthesis (one-pot reaction; SBBF formation, hydrolytic condensation, propagation), high stability (under different humidity, pH, light), bio-imaging applicability with low cellular toxicity, and an antibacterial effect within Gram-negative/Gram-positive strains. Based on our findings, we believe that these hybrid materials can pave the way for the further development of dye-hybrid materials and applications in various fields.