FOXP1 as a Potential ER Coregulator in Human Breast Cancer

Estrogen activates the estrogen receptor (ER) by recruiting various coregulators and cofactors, resulting in transcriptional regulation of target genes. Recently, we have shown that the FOXP1 forkhead transcription factor is a novel androgen-regulated coregulator for the androgen receptor (Biochem Biophys Res Commun, 374, 388-93, 2008). However, its role in breast cancer is still unknown.Here, we investigated the expression pattern of FOXP1 by immunohistochemistry in a series of 110 invasive breast cancers and compared it with clinicopathological factors. The expression of FOXP1 was detected in nuclei in 76 cases (69.1%) and correlated with expressions of ERα (P=0.001) and progesterone receptor (PgR) (P=0.003), while there was no association with age, lymph node status, size, or grade. Expression levels of FOXP1 mRNA are investigated by qRT-PCR using samples selectively obtained from breast cancer specimens with laser microdissection system (Zeiss Axiovert + P.A.L.M laser microdisection system). ERα, ERβ, and PgR mRNA levels were also measured.Then, we examined expression and function of FOXP1 in human breast cancer MCF-7 cells that possess functional ERα. The expression level of FOXP1 mRNA was up-regulated by estrogen treatment. In addition, estrogen-responsive element-driven luciferase reporter analysis showed that exogenously transfected FOXP1 increased estrogen-dependent transcriptional activity. We also observed that FOXP1 overexpression and knockdown could modulate the growth of MCF-7 cells.Taken together, these findings suggest that FOXP1 plays an important role as a potential ER coregulator in human breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4149.

Nanolitre liquid patterning in aqueous environments for spatially defined reagent delivery to mammalian cells

Microscale biopatterning enables regulation of cell-material interactions and cell shape, and enables multiplexed high-throughput studies in a cell- and reagent-efficient manner. The majority of available techniques rely on physical contact of a stamp, pin, or mask with mainly a dry surface. Inkjet and piezoelectric printing is carried out in a non-contact manner but still requires a substantially dry substrate to ensure fidelity of printed patterns. These existing methods, therefore, are limited for patterning onto delicate surfaces of living cells because physical contact or substantially dry conditions are damaging to them. Microfluidic patterning with laminar streams does enable non-contact patterning in fully aqueous environments but with limited throughput and reagent diffusion across interfacial flows. Here, we describe a polymeric aqueous two-phase system that enables patterning nanolitres of a reagent-containing aqueous phase, in arbitrary shapes, within a second aqueous phase covering a cell monolayer. With the appropriate medium formulation, reagents of interest remain confined to the patterned phase without significant diffusion. The fully aqueous environment ensures high reagent activity and cell viability. The utility of this strategy is demonstrated with patterned delivery of genetic materials to mammalian cells for phenotypic screening of gene expression and gene silencing.

Liquid plug propagation in flexible microchannels: A small airway model

In the present study, we investigate the effect of wall flexibility on the plug propagation and the resulting wall stresses in small airway models with experimental measurements and numerical simulations. Experimentally, a flexible microchannel was fabricated to mimic the flexible small airways using soft lithography. Liquid plugs were generated and propagated through the microchannels. The local wall deformation is observed instantaneously during plug propagation with the maximum increasing with plug speed. The pressure drop across the plug is measured and observed to increase with plug speed, and is slightly smaller in a flexible channel compared to that in a rigid channel. A computational model is then presented to model the steady plug propagation through a flexible channel corresponding to the middle plane in the experimental device. The results show qualitative agreements with experiments on wall shapes and pressure drops and the discrepancies bring up interesting questions on current field of modeling. The flexible wall deforms inward near the plug core region, the deformation and pressure drop across the plug increase with the plug speed. The wall deformation and resulting stresses vary with different longitudinal tensions, i.e., for large wall longitudinal tension, the wall deforms slightly, which causes decreased fluid stress and stress gradients on the flexible wall comparing to that on rigid walls; however, the wall stress gradients are found to be much larger on highly deformable walls with small longitudinal tensions. Therefore, in diseases such as emphysema, with more deformable airways, there is a high possibility of induced injuries on lining cells along the airways because of larger wall stresses and stress gradients.

Fine-tuning of the cytoplasmic Ca2+ concentration is essential for pollen tube growth

Pollen tube growth is crucial for the delivery of sperm cells to the ovule during flowering plant reproduction. Previous in vitro imaging of Lilium longiflorum and Nicotiana tabacum has shown that growing pollen tubes exhibit a tip-focused Ca(2+) concentration ([Ca(2+)]) gradient and regular oscillations of the cytosolic [Ca(2+)] ([Ca(2+)](cyt)) in the tip region. Whether this [Ca(2+)] gradient and/or [Ca(2+)](cyt) oscillations are present as the tube grows through the stigma (in vivo condition), however, is still not clear. We monitored [Ca(2+)](cyt) dynamics in pollen tubes under various conditions using Arabidopsis (Arabidopsis thaliana) and N. tabacum expressing yellow cameleon 3.60, a fluorescent calcium indicator with a large dynamic range. The tip-focused [Ca(2+)](cyt) gradient was always observed in growing pollen tubes. Regular oscillations of the [Ca(2+)](cyt), however, were rarely identified in Arabidopsis or N. tabacum pollen tubes grown under the in vivo condition or in those placed in germination medium just after they had grown through a style (semi-in vivo condition). On the other hand, regular oscillations were observed in vitro in both growing and nongrowing pollen tubes, although the oscillation amplitude was 5-fold greater in the nongrowing pollen tubes compared with growing pollen tubes. These results suggested that a submicromolar [Ca(2+)](cyt) in the tip region is essential for pollen tube growth, whereas a regular [Ca(2+)] oscillation is not. Next, we monitored [Ca(2+)] dynamics in the endoplasmic reticulum ([Ca(2+)](ER)) in relation to Arabidopsis pollen tube growth using yellow cameleon 4.60, which has a lower affinity for Ca(2+) compared with yellow cameleon 3.60. The [Ca(2+)](ER) in pollen tubes grown under the semi-in vivo condition was between 100 and 500 microm. In addition, cyclopiazonic acid, an inhibitor of ER-type Ca(2+)-ATPases, inhibited growth and decreased the [Ca(2+)](ER). Our observations suggest that the ER serves as one of the Ca(2+) stores in the pollen tube and cyclopiazonic acid-sensitive Ca(2+)-ATPases in the ER are required for pollen tube growth.

Gas-liquid two-phase flow patterns in rectangular polymeric microchannels: effect of surface wetting properties

Here we map gas-liquid two-phase flow regimes observed in polymeric microchannels with different wetting properties. We utilized video and confocal microscopy to examine two-phase flow patterns produced by parallel injection of air and water through a Y-shaped junction into a rectangular microchannel made of poly(dimethylsiloxane) (PDMS). We observed seven flow regimes in microchannels with hydrophobic walls, whereas only two flow patterns were identified in hydrophilic microchannels. Our study demonstrates that surface wettability has a profound influence on the spatial distribution of air and water moving in microchannels.

Analysis of flagellin perception mediated by flg22 receptor OsFLS2 in rice

Plants have sensitive perception systems that recognize various pathogen-derived molecules. We previously reported that rice detects flagellin from a rice-incompatible strain of gram-negative phytopathogenic bacterium, Acidovorax avenae, which induces subsequent immune responses involving cell death. The mechanism of flagellin perception in rice, however, has remained obscure. In this study, we found that flg22, a peptide derived from the flagellin N-terminus, induced weak immune responses without cell death in cultured rice cells. To elucidate the mechanism by which flg22 induced signaling in rice, we characterized OsFLS2, the rice ortholog of AtFLS2, which mediates flg22 perception. Heterologous expression of OsFLS2 functions in Arabidopsis, showing the conservation of the flg22 signaling pathway across divergent plant taxa. OsFLS2-overexpressing rice cultured cells generated stronger immune responses with the induction of cell death following stimulation with flg22 and flagellin. However, examination of the growth rate of the compatible strain in inoculated OsFLS2-overexpressing rice could not confirm bacterial growth suppression compared with wild-type rice. These results suggest that rice possesses a conserved flagellin perception system utilizing the FLS2 receptor which, when upregulated, hardly affects resistance against compatible A. avenae.

Two distinct forms of M-locus protein kinase localize to the plasma membrane and interact directly with S-locus receptor kinase to transduce self-incompatibility signaling in Brassica rapa

Many flowering plants possess systems of self-incompatibility (SI) to prevent inbreeding. In Brassica, SI recognition is controlled by the multiallelic gene complex (S-haplotypes) at the S-locus, which encodes both the male determinant S-locus protein 11 (SP11/SCR) and the female determinant S-receptor kinase (SRK). Upon self-pollination, the S-haplotype-specific interaction between the pollen-borne SP11 and the cognate stigmatic SRK receptor induces SI signaling in the stigmatic papilla cell and results in rejection of the self-pollen. Our genetic analysis of a self-compatible mutant revealed the involvement of a cytoplasmic protein kinase, M-locus protein kinase (MLPK), in the SI signaling, but its exact physiological function remains unknown. In this study, we identified two different MLPK transcripts, MLPKf1 and MLPKf2, which are produced using alternative transcriptional initiation sites and encode two isoforms that differ only at the N termini. While MLPKf1 and MLPKf2 exhibited distinct expression profiles, both were expressed in papilla cells. MLPKf1 localizes to the plasma membrane through its N-terminal myristoylation motif, while MLPKf2 localizes to the plasma membrane through its N-terminal hydrophobic region. Although both MLPKf1 and MLPKf2 could independently complement the mlpk/mlpk mutation, their mutant forms that lack the plasma membrane localization motifs failed to complement the mutation. Furthermore, a bimolecular fluorescence complementation assay revealed direct interactions between SRK and the MLPK isoforms in planta. These results suggest that MLPK isoforms localize to the papilla cell membrane and interact directly with SRK to transduce SI signaling.

Comparative analysis of the S-intergenic region in class-II S haplotypes of self-incompatible Brassica rapa (syn. campestris)

In the Brassica self-incompatibility (SI) system, a pollen determinant, SP11, is involved in dominance/recessive relationships in pollen SI phenotypes. In order to gain some insights into the genomic structure around the SP11 and the mechanisms that give dominance/recessive relationships, we characterized the genomic region containing SP11 and SRK genes in three pollen recessive class-II S haplotypes. The direction of transcription of S genes was completely conserved among class-II S haplotypes. However, the region between SP11 and SRK (S-intergenic region) was highly polymorphic without short repetitive sequences. In addition, we found a sequence similarity between the short repetitive sequence and 5'-upstream region of SP11. This sequence similarity was found to be potentially related to the expression of dominance relationships through the change of chromatin structure.

A balanced PGR5 level is required for chloroplast development and optimum operation of cyclic electron transport around photosystem I

PSI cyclic electron transport contributes markedly to photosynthesis and photoprotection in flowering plants. Although the thylakoid protein PGR5 (Proton Gradient Regulation 5) has been shown to be essential for the main route of PSI cyclic electron transport, its exact function remains unclear. In transgenic Arabidopsis plants overaccumulating PGR5 in the thylakoid membrane, chloroplast development was delayed, especially in the cotyledons. Although photosynthetic electron transport was not affected during steady-state photosynthesis, a high level of non-photochemical quenching (NPQ) was transiently induced after a shift of light conditions. This phenotype was explained by elevated activity of PSI cyclic electron transport, which was monitored in an in vitro system using ruptured chloroplasts, and also in leaves. The effect of overaccumulation of PGR5 was specific to the antimycin A-sensitive pathway of PSI cyclic electron transport but not to the NAD(P)H dehydrogenase (NDH) pathway. We propose that a balanced PGR5 level is required for efficient regulation of the rate of antimycin A-sensitive PSI cyclic electron transport, although the rate of PSI cyclic electron transport is probably also regulated by other factors during steady-state photosynthesis.

Gamete and embryo isolation and culture with microfluidics

Assisted reproductive technologies (ARTs) encompass some of the most exciting modern scientific developments that tremendously impacts society at many levels. Since the beginning of ARTs, scientists have studied and critically analyzed techniques in order to find ways to improve outcomes; however, little has changed with the actual technology and equipment for embryo in vitro production (IVP). New technologic possibilities exist with the escalating advancements of microfluidic technologies. Microfluidics is based on the behavior of liquids in a microenvironment. Although a young field, substantial research demonstrates the potential of this technology in gamete and embryo isolation and culture. In this review, we briefly discuss physical principles of microfluidics and highlight previous utilization of this technology. We then present designs and outcomes for microfluidic devices utilized thus far for different steps in the IVP process: gamete isolation and processing, fertilization, and embryo culture. Finally, we discuss and speculate on future use of microfluidics for assessing embryo viability and multiparametric analysis of embryo secretions and the integration of ART stage-specific capabilities that will lead to an "IVP-lab-on-a-chip".

Actin dynamics in papilla cells of Brassica rapa during self- and cross-pollination

The self-incompatibility system of the plant species Brassica is controlled by the S-locus, which contains S-RECEPTOR KINASE (SRK) and S-LOCUS PROTEIN11 (SP11). SP11 binding to SRK induces SRK autophosphorylation and initiates a signaling cascade leading to the rejection of self pollen. However, the mechanism controlling hydration and germination arrest during self-pollination is unclear. In this study, we examined the role of actin, a key cytoskeletal component regulating the transport system for hydration and germination in the papilla cell during pollination. Using rhodamine-phalloidin staining, we showed that cross-pollination induced actin polymerization, whereas self-pollination induced actin reorganization and likely depolymerization. By monitoring transiently expressed green fluorescent protein fused to the actin-binding domain of mouse talin, we observed the concentration of actin bundles at the cross-pollen attachment site and actin reorganization and likely depolymerization at the self-pollen attachment site; the results correspond to those obtained by rhodamine-phalloidin staining. We further showed that the coat of self pollen is sufficient to mediate this response. The actin-depolymerizing drug cytochalasin D significantly inhibited pollen hydration and germination during cross-pollination, further emphasizing a role for actin in these processes. Additionally, three-dimensional electron microscopic tomography revealed the close association of the actin cytoskeleton with an apical vacuole network. Self-pollination disrupted the vacuole network, whereas cross-pollination led to vacuolar rearrangements toward the site of pollen attachment. Taken together, our data suggest that self- and cross-pollination differentially affect the dynamics of the actin cytoskeleton, leading to changes in vacuolar structure associated with hydration and germination.

Determination of formoterol in rat plasma by liquid chromatography-electrospray ionisation mass spectrometry

A sensitive method for the determination of formoterol in rat plasma is described, using high performance liquid chromatographic separation with tandem mass spectrometry. Samples were purified using liquid-liquid extraction and separated on CAPCELL PAK C18 UG120 (2.0 x 150 mm) with a mobile phase consisting of a mixture of methanol- 50 mM ammonium hydrogen carbonate (1:1 v/v). Detection was performed with a TSQ 7000 mass spectrometer using positive ion electrospray ionisation, monitoring the shift from precursor ions for formoterol at m/z 344.9 to product ions of m/z 121.0. The limit of quantitation of the method was found to be 0.1 ng/ml, when using 0.1 ml plasma. Plasma concentrations of formoterol could be quantified from 0.15 to 7.01 ng/ml, allowing the analysis of samples up to 32 h after a single oral dose of formoterol fumarate (0.25 mg) to rats.

Characterization of the SP11/SCR high-affinity binding site involved in self/nonself recognition in brassica self-incompatibility

In Brassica self-incompatibility, the recognition of self/nonself pollen grains, is controlled by the S-locus, which encodes three highly polymorphic proteins: S-locus receptor kinase (SRK), S-locus protein 11 (SP11; also designated S-locus Cys-rich protein), and S-locus glycoprotein (SLG). SP11, located in the pollen coat, determines pollen S-haplotype specificity, whereas SRK, located on the plasma membrane of stigmatic papilla cells, determines stigmatic S-haplotype specificity. SLG shares significant sequence similarity with the extracellular domain of SRK and is abundant in the stigmatic cell wall, but its function is controversial. We previously showed that SP11 binds directly to its cognate SRK with high affinity (K(d) = 0.7 nM) and induces its autophosphorylation. We also found that an SLG-like, 60-kD protein on the stigmatic membrane forms a high-affinity binding site for SP11. Here, we show that the 60-kD stigmatic membrane protein is a truncated form of SRK containing the extracellular domain, transmembrane domain, and part of the juxtamembrane domain. A transiently expressed, membrane-anchored form of SRK exhibits high-affinity binding to SP11, whereas the soluble SRK (eSRK) lacking the transmembrane domain exhibits no high-affinity binding, as is the case with SLG. The different binding affinities of the membrane-anchored SRK and soluble eSRK or SLG will be significant for the specific perception of SP11 by SRK.

Pronation contracture of the forearm due to iatrogenic scar formation of the distal membranous part of the forearm interosseous membrane

A case of successful treatment of pronation contracture of the forearm due to iatrogenic scar formation in the distal membranous part of the interosseous membrane of the forearm is presented and the management of this problem is discussed.

Bag-1 and Bcl-2 gene transfer in malignant glioma: modulation of cell cycle regulation and apoptosis

Bag-1 is a heat shock 70 kDa (Hsp70)-binding protein that can collaborate with Bcl-2 in suppressing apoptosis under some conditions. Here, we report that 11 of 12 human glioma cell lines express Bag-1 protein in vitro. Moreover, 15 of 19 human glioblastomas expressed Bag-1 as assessed by immunohistochemistry in primary tumor specimens. To examine the biological effects of Bag-1 in glioma cells, we expressed Bag-1 or Bcl-2 transgenes in 2 human malignant glioma cell lines, LN-18 and LN-229. Bag-1 significantly slowed glioma cell growth and reduced clonogenicity of both cell lines in vitro. Coexpressed Bcl-2 abrogated these effects of Bag-1. Intracranial LN-229 glioma xenografts implanted into nude mice revealed a substantial growth advantage afforded by Bcl-2. Bag-1 had no such effect, either in the absence or presence of Bcl-2. Upon serum starvation in vitro, Bcl-2 prevented cell death whereas Bag-1 did not. Both Bcl-2 and Bag-1 slowed proliferation of serum-starved cells when expressed alone. Importantly, coexpression of Bcl-2 and Bag-1 provided a distinct growth advantage under conditions of serum starvation that is probably the result of (i) the death-preventing activity of Bcl-2 and (ii) the property of Bag-1 to overcome a Bcl-2-mediated enhancement of exit from the cell cycle. In contrast to these Bcl-2/Bag-1 interactions observed under serum starvation conditions, Bag-1 did not further enhance the strong protection from staurosporine-, CD95 (Fas/Apo1) ligand-, Apo2 ligand (TRAIL)- or chemotherapeutic drug-induced apoptosis afforded by Bcl-2. Taken together, these results indicate a role for Bag-1/Bcl-2 interactions in providing a survival advantage to cancer cells in a deprived microenvironment that may be characteristic of ischemic/hypoxic tumors such as human glioblastoma multiforme, and suggest that Bcl-2/Bag-1 interactions also modulate cell proliferation.

Dominance relationships between self-incompatibility alleles controlled by DNA methylation

In crucifers, the pollen S-determinant gene, SP11, is sporophytically expressed in the anther tapetum, and the pollen self-incompatibility phenotype is determined by the dominance relationships between the two S-haplotypes it carries. We report here that 5' promoter sequences of recessive SP11 alleles are specifically methylated in the tapetum before the initiation of SP11 transcription. These results suggest that tissue-specific monoallelic de novo DNA methylation is involved in determining the dominance interactions that determine the cruciferous self-incompatibility phenotype.

Comparison of Campylobacter isolated from humans and food-producing animals in Japan

AIMS

To compare the antimicrobial resistance, serotypes and flagellin gene types of Campylobacter isolated from humans and food-producing animals and thereby facilitate elucidation of the origin of Campylobacter causing human infection in Japan.

METHODS AND RESULTS

The MIC values of ampicillin, dihydrostreptomycin, gentamicin, erythromycin, oxytetracycline, nalidixic acid and enrofloxacin for Campylobacter isolated from humans (134 isolates), cattle (38 isolates), pigs (69 isolates), layers (84 isolates) and broilers (51 isolates) were compared. The MIC(90) values of ampicillin for Campylobacter jejuni isolates from poultry were higher than those from humans and cattle. Campylobacter coli that was resistant to dihydrostreptomycin and erythromycin was observed at a higher frequency in humans and pigs than in poultry. The restriction fragment profiles of flaA of human, bovine and broiler isolates were analysed by clustering, and the isolates were classified into five clusters. Cluster I contained only human and bovine isolates. Clusters III, IV and V contained human, bovine and broiler isolates.

CONCLUSIONS

Campylobacter isolates from humans included isolates that exhibited characteristics identical to those of the bovine, porcine and poultry isolates.

SIGNIFICANCE AND IMPACT OF THE STUDY

In addition to poultry, cattle and pigs are believed to be sources of campylobacteriosis in Japan.

Duplicated SP11 genes produce alternative transcripts in the S15 haplotype of Brassica oleracea

Self-incompatibility (SI) discriminating self and non-self pollen is regulated by S-locus genes in Brassica. In most S haplotypes, a set of three highly polymorphic genes, SLG, SRK, and SP11, is located at the S-locus region. In the present study, we found duplicated SP11 genes, S15-SP11a, S15-SP11b, and S15-SP11b', in the self-incompatible S15 haplotype of B. oleracea. RNA gel blot and reverse transcription polymerase chain reaction (RT-PCR) analyses showed that two different sizes of SP11 transcripts were specifically detected in anther tissues: a 0.65-kb transcript corresponded to S15-SP11a (an exon-1 region of S15-SP11b was also co-transcribed in some cases), and a 1.4-kb transcript contained the duplicated three genes, S15-SP11a, S15-SP11b, and an exon-1 region of S15-SP11b', all three of which were connected to intergenic spacer regions.

Self-incompatibility in plants

Sexual reproduction in many flowering plants involves self-incompatibility (SI), which is one of the most important systems to prevent inbreeding. In many species, the self-/nonself-recognition of SI is controlled by a single polymorphic locus, the S-locus. Molecular dissection of the S-locus revealed that SI represents not one system, but a collection of divergent mechanisms. Here, we discuss recent advances in the understanding of three distinct SI mechanisms, each controlled by two separate determinant genes at the S-locus. In the Brassicaceae, the determinant genes encode a pollen ligand and its stigmatic receptor kinase; their interaction induces incompatible signaling(s) within the stigma papilla cells. In the Solanaceae-type SI, the determinants are a ribonuclease and an F-box protein, suggesting the involvement of RNA and protein degradation in the system. In the Papaveraceae, the only identified female determinant induces a Ca2+-dependent signaling network that ultimately results in the death of incompatible pollen.

Ca2+ dynamics in a pollen grain and papilla cell during pollination of Arabidopsis

Ca2+ dynamics in the growing pollen tube have been well documented in vitro using germination assays and Ca2+ imaging techniques. However, very few in vivo studies of Ca2+ in the pollen grain and papilla cell during pollination have been performed. We expressed yellow cameleon, a Ca2+ indicator based on green fluorescent protein, in the pollen grains and papilla cells of Arabidopsis (Arabidopsis thaliana) and monitored Ca2+ dynamics during pollination. In the pollen grain, [Ca2+]cyt increased at the potential germination site soon after hydration and remained augmented until germination. As in previous in vitro germination studies, [Ca2+]cyt oscillations were observed in the tip region of the growing pollen tube, but the oscillation frequency was faster and [Ca2+]cyt was higher than had been observed in vitro. In the pollinated papilla cell, remarkable increases in [Ca2+]cyt occurred three times in succession, just under the site of pollen-grain attachment. [Ca2+]cyt increased first soon after pollen hydration, with a second increase occurring after pollen protrusion. The third and most remarkable [Ca2+]cyt increase took place when the pollen tube penetrated into the papilla cell wall.

Ischaemic contracture in an infant's forearm--a case report

We present a case of a gradually developing ischaemic contracture of the forearm muscles of an infant who developed without any trauma or acute gangrene at birth. Release of the middle and ring finger digitorum profundus muscles and pronator quadratus at 2 years of age corrected the deformity. Histopathology showed no evidence of fibromatosis or any other tumor. Although a dynamic splint was used to maintain the range of motion, the range of the middle finger motion deteriorated gradually 2 years after surgery. Though the pathogenesis of this problem was unclear, we assume that it was caused by fibrosis of muscles as a result of bleeding before or during delivery.

Acute Painful Neuropathy Restricted to the Abdomen following Rapid Glycaemic Control in Type 2 Diabetes

A 46-year-old Japanese man with type 2 diabetes mellitus, whose only diabetic complication was simple retinopathy, developed acute painful neuropathy. This presented as paresthesia and hyperesthesia restricted to the abdomen. The patient's haemoglobin A1c had dropped from 12% to 7.5% within 5 months, following a rapid improvement in glycaemic control. On investigation, there were no indications of disease in the intraabdominal area. Nerve conduction studies were consistent with mild sensorimotor peripheral and autonomic neuropathy. The patient required medication (mexiletine, sulpiride and imipramine hydrochloride) to control the pain. Four months after presentation, the symptoms showed a dramatic improvement and the treatment for pain relief was discontinued without any recurrence of paresthesia or hyperesthesia in the patient's abdomen. This was a very unusual case of diabetic post-treatment painful neuropathy in which the prominent features were severe pain, paresthesia and hyperesthesia restricted to the abdomen.

Rice cDNA microarray-based gene expression profiling of the response to flagellin perception in cultured rice cells

Incompatible strains of Acidovorax avenae elicit an immune response in cultured rice cells, with immunity specifically induced by the flagellin of the incompatible strain. To identify genes regulated by flagellin perception signaling in cultured rice cells, gene expression patterns were analyzed with rice cDNA microarrays, including 3,353 independent rice cDNA clones. In all, 131 genes were differentially expressed between incompatible and compatible interactions. K-means clustering showed that 94 genes were upregulated and 32 genes were downregulated during incompatible interactions, whereas only 5 genes were upregulated during compatible interactions. Among the 126 genes that were up- or downregulated during incompatible interactions, expression of 46 genes was decreased when cultured rice cells were inoculated with a flagellin-deficient incompatible strain (delta fla1141-2), indicating that approximately 37% of the 126 genes were directly controlled by flagellin perception. Real-time reverse-transcription polymerase chain reaction analysis using flagellins purified from incompatible or compatible strains was performed to confirm flagellin-regulated expression of candidate genes selected by microarray analysis. Results showed that induction of some genes involved in the immune response is regulated not only by the flagellin perception pathway, but also by another recognition molecule-perception pathway.

Acute hyposmia in type 2 diabetes

During treatment for type 2 diabetes with a diabetic diet (without medication), a 61-year-old Japanese man suddenly developed hyposmia. The fasting plasma glucose was 208 mg/dl and haemoglobin A1c was 8.6%. On investigation, there were no indications of disease of the brain, or the nasal or paranasal sinuses. The intravenous olfaction test yielded no response, indicating suspected neural hyposmia. After 6 months, the symptoms of hyposmia improved without medication, and the intravenous olfaction test results were normal. This clinical course is very similar to that seen with diabetic neuropathy of the third and sixth cranial nerves. We speculate that hyposmia in this case may have been caused by diabetic mononeuropathy of the first cranial nerve.

A Membrane-Anchored Protein Kinase Involved in Brassica Self-Incompatibility Signaling

Self-incompatibility (SI) response in Brassica is initiated by haplotype-specific interactions between the pollen-borne ligand S locus protein 11/SCR and its stigmatic S receptor kinase, SRK. This binding induces autophosphorylation of SRK, which is then thought to trigger a signaling cascade that leads to self-pollen rejection. A recessive mutation of the modifier (m) gene eliminates the SI response in stigma. Positional cloning of M has revealed that it encodes a membrane-anchored cytoplasmic serine/threonine protein kinase, designated M locus protein kinase (MLPK). Transient expression of MLPK restores the ability of mm papilla cells to reject self-pollen, suggesting that MLPK is a positive mediator of Brassica SI signaling.

Calcium crystals in the anther of Petunia: the existence and biological significance in the pollination process

Using an X-ray microanalysis system fitted with variable-pressure scanning electron microscopy, we noted that many calcium crystals accumulated under the stomium in the anther of Petunia. When the anther was dehisced and pollen grains were released from the stomata, the calcium crystals adhered to pollen grains and moved to the stigma together with pollen grains. In contrast, an X-ray microanalysis of the stigma surface before pollination detected no calcium emission on the stigma surface. Furthermore, pollen germination and pollen tube growth in medium without Ca occurred as in complete medium. However, after the pollen grains had been washed with abundant germination medium without calcium, pollen germination in the medium without Ca was inhibited. These results show that the calcium crystals dissolved in the aqueous drop under the exudate on the stigma and supplied calcium ions for pollen germination. In addition, calcium crystals were produced not only in the anther of Petunia but also in Nicotiana, suggesting that calcium crystals supply pollen grains with the calcium ions required for pollen germination and serve to improve reproduction efficiency in Solanaceae.

Structure of the male determinant factor for Brassica self-incompatibility

Many flowering plants possess a self-incompatibility system to prevent inbreeding. In Brassica rapa, self/non-self recognition in mating is established through S-haplotype-specific interactions between stigma receptors and S-locus protein 11 (SP11, also called S-locus cysteine-rich protein) that is encoded at the highly polymorphic S-locus. Here we describe the solution structure of the SP11 protein of the S8-haplotype (S8-SP11), which specifically binds to the stigma factor of the same haplotype. It folds into an alpha/beta sandwich structure that resembles those of plant defensins. Residues important for structural integrity are highly conserved among the allelic SP11s, suggesting the existence of a common folding pattern. Structure-based sequence alignment and homology modeling of allelic SP11 identified a hyper-variable (HV) region, which is thought to form a loop that bulges out from the body of the protein that is amenable to solvent exposure. We suggest that the HV region could serve as a specific binding site for the stigma receptor.

Three-dimensional architecture of ribosomal DNA within barley nucleoli revealed with electron microscopy

To elucidate the topological positioning of ribosomal RNA genes (rDNA) and nucleolar structure in three dimensions, we examined the localization of rDNA using in situ hybridization (ISH) analysis by scanning electron microscopy (SEM). The rDNA genes within the three-dimensional architecture of nucleoli were detected on chromatin fibers that connect a thick strand-like structure and a protrusion of rDNA into the inner nuclear hole where the nucleolus is formed. This novel use of ISH together with SEM is useful for the analysis of nucleolar structure in detail. Furthermore, rDNA was detected at the periphery of the fibrillar centers (FCs) of the nucleolus using immuno-gold labeling together with transmission electron microscopy (TEM). In situ hybridization with TEM confirmed that rDNA is naked and thus active in the FCs of nucleoli; ISH with SEM confirmed that rDNA is not covered with ribonucleo proteins at the protruding point and is thus inactive. We also show that the distribution pattern of FCs differs from sample to sample. These results indicate that rDNA is transcribed dynamically in a time- and region-specific manner over the course of the cell cycle.

The S haplotypes lacking SLG in the genome of Brassica rapa

Self-incompatibility (SI) discriminating self- and non-self pollen is regulated by S-locus genes in Brassica. In most of the S haplotypes, a highly polymorphic S-locus glycoprotein ( SLG) gene is tightly linked to genes for the SI determinants, S-receptor kinase ( SRK) and SP11, although the precise function of SLG in SI has not been clarified. In the present study, we performed DNA gel blot analysis for S(32), S(33), and S(36) haplotypes of Brassica rapa showing normal SI phenotypes and concluded that there might be no SLG in their genome. RNA gel blot analysis of the SLG-less S haplotypes indicated the possible existence of eSRK transcripts in the stigma. These three S haplotypes are useful resources to discern the molecular mechanism of the SI reaction without SLG.

Flagellin from an incompatible strain of Acidovorax avenae mediates H2O2 generation accompanying hypersensitive cell death and expression of PAL, Cht-1, and PBZ1, but not of Lox in rice

Acidovorax avenae causes a brown stripe disease in monocot plants. We recently reported that a rice-incompatible strain of A. avenae caused hypersensitive cell death in rice and that the flagellin of the incompatible strain was involved in this response. The incompatible strain induced the rapid generation of H2O2 accompanying hypersensitive cell death and the expression of defense genes such as PAL, Cht-1, PBZ1, and LOX, whereas the compatible strain did not. The purified incompatible flagellin also induced the expression of PAL, Cht-1, and PBZ1, but LOX expression was not induced by the incompatible flagellin. PAL and LOX enzymatic activities were increased by inoculation with the incompatible strain, whereas only PAL activity was increased by the incompatible flagellin. Interestingly, the flagellin-deficient incompatible strain lost the ability to generate H2O2 and induce hypersensitive cell death, but PAL, Cht-1, and PBZ1 expression still were induced by inoculation with the deficient strain, suggesting that induction of these genes is regulated not only by flagellin but also by some other signal. Thus, the incompatible flagellin of A. avenae is a specific elicitor in rice, but it is not the only factor capable of inducing the rice defense system.

Immunohistochemical studies on translocation of pollen S-haplotype determinant in self-incompatibility of Brassica rapa

The self-incompatibility system in Brassica is controlled by the S-locus, which contains S-receptor kinase (SRK) and S-locus protein 11 (SP11). SRK and SP11 control stigma and pollen S-haplotype specificity, respectively. SP11 binding to SRK induces the autophosphorylation of SRK, which triggers the signaling cascade that results in the rejection of self-pollen. The localization of SP11 protein during pollen development and pollination, however, have never been demonstrated. In this study, we examined the localization of S(8)-SP11 protein in the anther or pollinated stigma by immuno-electron microscopy. The immunostaining suggested that S(8)-SP11 was secreted from the tapetal cell into the anther locule as a cluster and translocated to the pollen surface at the early developmental stage of the anther. During the pollination process, SP11 was translocated from the pollen surface to the papilla cell, and then penetrated the cuticle layer of the papilla cell to diffuse across the pectin cellulose layer. Furthermore, SP11 protein could only penetrate the cuticle layer of the papilla cell in the presence of pollen grains, and could not penetrate on its own. This suggests that another factor from the pollen grain is needed for SP11 protein to penetrate the papilla cell wall.

Genomic organization of the S-locus region of Brassica

To gain some insights into the structure of the S-locus and the mechanisms that have kept its diversity, a 75-kb genomic fragment containing the self-incompatibility (S) locus region was isolated from the S12-haplotype of Brassica rapa and compared with those of other S-haplotypes. The region around the S determinant genes was highly polymorphic and filled with S-haplotype-specific intergenic sequences. The diverse genomic structure must contribute to the suppression of recombination at the S-locus.

Comparative analysis of the self-incompatibility (S-) locus region of Prunus mume: identification of a pollen-expressed F-box gene with allelic diversity

BACKGROUND

Self-incompatibility (SI) in the Solanaceae, Rosaceae and Scrophulariaceae is gametophytically controlled by a single polymorphic locus, termed the S-locus. To date, the only known S-locus product is a polymorphic ribonuclease, termed S-RNase, which is secreted by stylar tissue and thought to act as a cytotoxin that degrades the RNA of incompatible pollen tubes. However, understanding how S-RNase causes S-haplotype specific inhibition of pollen tubes has been hampered by the lack of a cloned pollen S-determinant gene.

RESULTS

To identify the pollen S-determinant gene, we investigated the genomic structure of the S-locus region of the S1- and S7-haplotypes of Prunus mume (Japanese apricot), and identified 13 genes around the S-RNase gene. Among them, only one F-box gene, termed SLF (S-locus F-box), fulfilled the conditions for a pollen S-determinant gene: (i) together with the S-RNase gene, it is located within the highly divergent genomic region of the S-locus, (ii) it exhibits S-haplotype specific diversity among three analysed S-haplotypes, and (iii) it is specifically expressed in pollen, but not in the styles or leaves.

CONCLUSION

The results indicate that SLF is a prime candidate for the pollen S-determinant gene of SI.

Recombinant human basic fibroblast growth factor (bFGF) stimulates periodontal regeneration in class II furcation defects created in beagle dogs

Several growth factors (or cytokines) have been recently investigated for their use as potential therapeutics for periodontal tissue regeneration. The objective of this study was to evaluate periodontal tissue regeneration, including new bone and cementum formation, following topical application of recombinant basic fibroblast growth factor (bFGF, FGF-2) to furcation class II defects. Twelve furcation class II bone defects were surgically created in six beagle dogs, then recombinant bFGF (30 micro g/site) + gelatinous carrier was topically applied to the bony defects. Six weeks after application, periodontal regeneration was analyzed. In all sites where bFGF was applied, periodontal ligament formation with new cementum deposits and new bone formation was observed histomorphometrically, in amounts greater than in the control sites. Basic FGF-applied sites exhibited significant regeneration as represented by the new bone formation rate (NBR) (83.6 +/- 14.3%), new trabecular bone formation rate (NTBR) (44.1 +/- 9.5%), and new cementum formation rate (NCR) (97.0 +/- 7.5%). In contrast, in the carrier-only sites, the NBR, NTBR, and NCR were 35.4 +/- 8.9%, 16.6 +/- 6.2%, and 37.2 +/- 15.1%, respectively. Moreover, no instances of epithelial down growth, ankylosis, or root resorption were observed in the bFGF-applied sites examined. The present results indicate that topical application of bFGF can enhance considerable periodontal regeneration in artificially created furcation class II bone defects of beagle dogs.

Inhibitory effects of formoterol on lipopolysaccharide-induced premature delivery through modulation of proinflammatory cytokine production in mice

Previous studies have demonstrated that formoterol, a beta2-adrenoceptor agonist, has potent tocolytic effects in rats. The aim of the present study was to determine whether formoterol treatment affects proinflammatory cytokine production in a lipopolysaccharide (LPS)-treated premature delivery mouse model. Formoterol was continuously administered by osmotic pump and the number of fetuses in the uteri were counted. Samples of amniotic fluid and plasma were collected 8 and 16 h after systemic administration of LPS. LPS induced premature delivery and an increase in prostaglandin F(2alpha) (PGF(2alpha)), interleukin 1alpha (IL-1alpha), IL-6 and IL-10 in the amniotic fluid, and an increase in IL-6 in plasma. Formoterol blocked all changes except the increase in IL-10. These data indicate that formoterol exerts inhibitory effects on proinflammatory cytokine production, and these effects may play an important role in the prevention of premature delivery.

Molecular mechanism of self-recognition in Brassica self-incompatibility

In most self-incompatible plant species, recognition of self-pollen is controlled by a single locus, termed the S-locus. In Brassica, genetic dissection of the S-locus has revealed the presence of three highly-polymorphic genes: S-receptor kinase (SRK), S-locus protein 11 (SP11) (also known as S-locus cysteine-rich protein; SCR) and S-locus glycoprotein (SLG). SRK encodes a membrane-spanning serine/threonine kinase that determines the S-haplotype specificity of the stigma. SP11 encodes a small cysteine-rich protein that determines the S-haplotype specificity of pollen. SLG encodes a secreted form of stigma protein similar to the extracellular domain of SRK. Recent biochemical studies have revealed that SP11 functions as the sole ligand for its cognate SRK receptor complex. Their interaction induces the autophosphorylation of SRK, which is expected to trigger the signalling cascade that results in the rejection of self-pollen. This so-called ligand-receptor complex interaction and receptor activation occur in an S-haplotype-specific manner, and this specificity is almost certainly the basis for self-pollen recognition.

Linear dominance relationship among four class-II S haplotypes in pollen is determined by the expression of SP11 in Brassica self-incompatibility

Self-incompatibility (SI) prevents self-fertilization by rejecting pollen from plants with the same S phenotype. The Brassica SI system is controlled sporophytically by multiple alleles at the single locus, S, and dominance relationships among S haplotypes are observed in both stigma and pollen. We have identified previously five different class-II S haplotypes in Brassica campestris. Here, we performed test-crosses between S heterozygotes and their respective parental S homozygotes for four of these class-II S haplotypes, and observed a linear dominance relationship on the pollen side. To determine how this relationship is controlled, we performed RNA gel blot analyses for six S heterozygotes and their respective parental S homozygotes using the corresponding SP11 clone as a probe. In all six S heterozygotes, SP11 derived from a dominant haplotype was predominantly expressed, and SP11 derived from a recessive haplotype was repressed. Thus, the linear dominance relationship of the SI phenotype on the pollen side is regulated by the expression of SP11.