Global transcriptome profiles of Camellia sinensis during cold acclimation

Background

Tea is the most popular non-alcoholic health beverage in the world. The tea plant (Camellia sinensis (L.) O. Kuntze) needs to undergo a cold acclimation process to enhance its freezing tolerance in winter. Changes that occur at the molecular level in response to low temperatures are poorly understood in tea plants. To elucidate the molecular mechanisms of cold acclimation, we employed RNA-Seq and digital gene expression (DGE) technologies to the study of genome-wide expression profiles during cold acclimation in tea plants.

Results

Using the Illumina sequencing platform, we obtained approximately 57.35 million RNA-Seq reads. These reads were assembled into 216,831 transcripts, with an average length of 356 bp and an N50 of 529 bp. In total, 1,770 differentially expressed transcripts were identified, of which 1,168 were up-regulated and 602 down-regulated. These include a group of cold sensor or signal transduction genes, cold-responsive transcription factor genes, plasma membrane stabilization related genes, osmosensing-responsive genes, and detoxification enzyme genes. DGE and quantitative RT-PCR analysis further confirmed the results from RNA-Seq analysis. Pathway analysis indicated that the “carbohydrate metabolism pathway” and the “calcium signaling pathway” might play a vital role in tea plants’ responses to cold stress.

Conclusions

Our study presents a global survey of transcriptome profiles of tea plants in response to low, non-freezing temperatures and yields insights into the molecular mechanisms of tea plants during the cold acclimation process. It could also serve as a valuable resource for relevant research on cold-tolerance and help to explore the cold-related genes in improving the understanding of low-temperature tolerance and plant-environment interactions.

Population sequencing enhances understanding of tea plant evolution

Tea is an economically important plant characterized by a large genome, high heterozygosity, and high species diversity. In this study, we assemble a 3.26-Gb high-quality chromosome-scale genome for the 'Longjing 43' cultivar of Camellia sinensis var. sinensis. Genomic resequencing of 139 tea accessions from around the world is used to investigate the evolution and phylogenetic relationships of tea accessions. We find that hybridization has increased the heterozygosity and wide-ranging gene flow among tea populations with the spread of tea cultivation. Population genetic and transcriptomic analyses reveal that during domestication, selection for disease resistance and flavor in C. sinensis var. sinensis populations has been stronger than that in C. sinensis var. assamica populations. This study provides resources for marker-assisted breeding of tea and sets the foundation for further research on tea genetics and evolution.

Reciprocity between membranous and nuclear expression of beta-catenin in colorectal tumours

beta-Catenin has a central role not only in linking the cadherin-mediated cell adhesion system but also in the intercellular signalling pathway. To investigate alterations of beta-catenin in the development of colorectal carcinoma, the pattern of beta-catenin expression was studied using immunohistochemistry in 74 sporadic colorectal adenomas, in histologically normal mucosa adjacent to 65 of these adenomas, and in 52 carcinomas arising in adenomas. All normal epithelia displayed cell boundary staining for beta-catenin. Adenomas and carcinomas showed varying degrees of membranous staining. However, some tumours also showed nuclear staining of beta-catenin protein. Decreased membranous and increased nuclear beta-catenin staining were associated with increasing degrees of dysplasia in adenomas (P < 0.005, P < 0.05, respectively). Carcinomas manifested significantly reduced membranous, but enhanced nuclear beta-catenin expression compared with their associated adenomas (P < 0.001, P < 0.005, respectively). An inverse correlation was found between decreased membranous and increased nuclear staining of beta-catenin in both adenomas and carcinomas (P < 0.025, P < 0.05, respectively). The data confirm that reduced membranous and increased nuclear expression of beta-catenin is associated with the progression of colorectal adenomas to carcinomas. Our results also suggest that decreased membranous expression of beta-catenin may result from aberrant localisation of the protein in the cell nucleus.

Effects of cold acclimation on sugar metabolism and sugar-related gene expression in tea plant during the winter season

Sugar plays an essential role in plant cold acclimation (CA), but the interaction between CA and sugar remains unclear in tea plants. In this study, during the whole winter season, we investigated the variations of sugar contents and the expression of a large number of sugar-related genes in tea leaves. Results indicated that cold tolerance of tea plant was improved with the development of CA during early winter season. At this stage, starch was dramatically degraded, whereas the content of total sugars and several specific sugars including sucrose, glucose and fructose were constantly elevated. Beyond the CA stage, the content of starch was maintained at a low level during winter hardiness (WH) period and then was elevated during de-acclimation (DC) period. Conversely, the content of sugar reached a peak at WH stage followed by a decrease during DC stage. Moreover, gene expression results showed that, during CA period, sugar metabolism-related genes exhibited different expression pattern, in which beta-amylase gene (CsBAM), invertase gene (CsINV5) and raffinose synthase gene (CsRS2) engaged in starch, sucrose and raffinose metabolism respectively were solidly up-regulated; the expressions of sugar transporters were stimulated in general except the down-regulations of CsSWEET2, 3, 16, CsERD6.7 and CsINT2; interestingly, the sugar-signaling related CsHXK3 and CsHXK2 had opposite expression patterns at the early stage of CA. These provided comprehensive insight into the effects of CA on carbohydrates indicating that sugar accumulation contributes to tea plant cold tolerance during winter season, and a simply model of sugar regulation in response to cold stimuli is proposed.

Phytoremediation of heavy and transition metals aided by legume-rhizobia symbiosis

Legumes are important for nitrogen cycling in the environment and agriculture due to the ability of nitrogen fixation by rhizobia. In this review, we introduce an important and potential role of legume-rhizobia symbiosis in aiding phytoremediation of some metal contaminated soils as various legumes have been found to be the dominant plant species in metal contaminated areas. Resistant rhizobia used for phytoremediation could act on metals directly by chelation, precipitation, transformation, biosorption and accumulation. Moreover, the plant growth promoting (PGP) traits of rhizobia including nitrogen fixation, phosphorus solubilization, phytohormone synthesis, siderophore release, and production of ACC deaminase and the volatile compounds of acetoin and 2, 3-butanediol may facilitate legume growth while lessening metal toxicity. The benefits of using legumes inoculated with naturally resistant rhizobia or recombinant rhizobia with enhanced resistance, as well as co-inoculation with other plant growth promoting bacteria (PGPB) are discussed. However, the legume-rhizobia symbiosis appears to be sensitive to metals, and the effect of metal toxicity on the interaction between legumes and rhizobia is not clear. Therefore, to obtain the maximum benefits from legumes assisted by rhizobia for phytoremediation of metals, it is critical to have a good understanding of interactions between PGP traits, the symbiotic plant-rhizobia relationship and metals.

Early expression of cyclo-oxygenase-2 during sporadic colorectal carcinogenesis

Regular administration of non-steroidal anti-inflammatory drugs (NSAIDs) may reduce the incidence of colorectal cancer by targeting cyclo-oxygenase-2 (Cox-2), a key enzyme in arachidonic acid metabolism. To evaluate the role of Cox-2 in sporadic colorectal cancer development, Cox-2 expression was investigated by immunohistochemistry in 85 adenomas, 53 carcinomas, 34 hyperplastic lesions and 104 samples of histologically normal mucosa adjacent to adenoma or carcinoma. In addition, Cox-2 mRNA expression was assessed by reverse transcription-polymerase chain reaction (RT-PCR) in six adenomas and 14 carcinomas with paired grossly normal mucosa. Immunohistochemistry for the proliferation-associated antigen Ki-67 and in situ end labelling for demonstrating apoptotic bodies were also used to analyse the associations between Cox-2 expression and proliferation and apoptosis. Cox-2 protein expression was increased in 76/85 (89.4 per cent) adenomas and 44/53 (83.0 per cent) carcinomas compared with normal mucosa. Cox-2 protein expression was unrelated either to the degree of dysplasia or to the size of the adenomas (p > 0.50, p > 0.10, respectively) or to differentiation, Dukes stage or lymph node metastasis of carcinomas (all p > 0.50). Interestingly, 20/34 (58.8 per cent) hyperplastic lesions adjacent to adenomas or carcinomas displayed expression higher than in normal mucosa (18.3 per cent) (p < 0.0001) but lower than in adenomas or carcinomas (p < 10(-5), p < 0.001, respectively). There were no correlations between Cox-2 protein expression and proliferative or apoptotic index in either adenomas or carcinomas (all p > 0.25). Cox-2 mRNA expression was significantly increased in adenomas and carcinomas compared with normal mucosa (p < 0.005, p < 0.001, respectively). There were no differences between adenomas and carcinomas in either protein or mRNA levels (p > 0.25, p > 0.90, respectively). These data indicate that enhanced expression of Cox-2 occurs early during colorectal carcinogenesis and may contribute to tumour formation.

Diverse Colletotrichum species cause anthracnose of tea plants (Camellia sinensis (L.) O. Kuntze) in China

Anthracnose caused by Colletotrichum is one of the most severe diseases that can afflict Camellia sinensis. However, research on the diversity and geographical distribution of Colletotrichum in China remain limited. In this study, 106 Colletotrichum isolates were collected from diseased leaves of Ca. sinensis cultivated in the 15 main tea production provinces in China. Multi-locus phylogenetic analysis coupled with morphological identification showed that the collected isolates belonged to 11 species, including 6 known species (C. camelliae, C. cliviae, C. fioriniae, C. fructicola, C. karstii, and C. siamense), 3 new record species (C. aenigma, C. endophytica, and C. truncatum), 1 novel species (C. wuxiense), and 1 indistinguishable strain, herein described as Colletotrichum sp. Of these species, C. camelliae and C. fructicola were the dominant species causing anthracnose in Ca. sinensis. In addition, our study provided further evidence that phylogenetic analysis using a combination of ApMat and GS sequences can be used to effectively resolve the taxonomic relationships within the C. gloeosporioides species complex. Finally, pathogenicity tests suggested that C. camelliae, C. aenigma, and C. endophytica are more invasive than other species after the inoculation of the leaves of Ca. sinensis.

Basal ganglia surface morphology and the effects of stimulant medications in youth with attention deficit hyperactivity disorder

OBJECTIVE

Disturbances in the basal ganglia portions of cortico-striato-thalamo-cortical circuits likely contribute to the symptoms of attention deficit hyperactivity disorder (ADHD). The authors examined the morphologic features of the basal ganglia nuclei (caudate, putamen, and globus pallidus) in children with ADHD.

METHOD

A total of 104 individuals (combined-type ADHD patients: N=47; healthy comparison subjects: N=57), aged 7 to 18 years, were examined in a cross-sectional case-control study using anatomical magnetic resonance imaging. Conventional volumes and the surface morphology for the basal ganglia were measured.

RESULTS

Overall volumes were significantly smaller only in the putamen. Analysis of the morphological surfaces revealed significant inward deformations in each of the three nuclei, localized primarily in portions of these nuclei that are components of limbic, associative, and sensorimotor pathways in the cortico-striato-thalamo-cortical circuits in which these nuclei reside. The more prominent these inward deformations were in the patient group, the more severe the ADHD symptoms. Surface analyses also demonstrated significant outward deformations of all basal ganglia nuclei in the ADHD children treated with stimulants compared with those ADHD youth who were untreated. These stimulant-associated enlargements were in locations similar to the reduced volumes detected in the ADHD group relative to the comparison group. The outward deformations associated with stimulant medications attenuated the statistical effects of the primary group comparisons.

CONCLUSIONS

These findings potentially represent evidence of anatomical dysregulation in the circuitry of the basal ganglia in children with ADHD and suggest that stimulants may normalize morphological features of the basal ganglia in children with the disorder.

Effect of dried distillers’ grains from wheat on diet digestibility and performance of feedlot cattle

In a 55-d backgrounding period, 120 (n = 22) British cross heifers (312 ± 20 kg) received diets containing 55% barley silage, 5% supplement and 0 (n = 24), 20 (n = 24), or 40% (n = 22) wheat distillers’ dried grains with solubles (DDGS). The remainder of the diet was steam-rolled barley. Replacing half (20%) or all (40%) of the barley with DDGS did not affect dry matter intake (DMI) (P = 0.61), average daily gain (ADG) (P = 0.86), or gain:feed (P = 0.94), indicating the energy content of DDGS is similar to that of barley when included in backgrounding diets. During a 133-d finishing period, DDGS were included at 0, 20, 40, or 60% of diet dry matter (DM) or at 60% plus additional calcium, provided as 1% limestone (n = 24). Additional calcium did not (P > 0.1) affect DMI, ADG, or gain:feed. Increasing levels of DDGS linearly increased (P = 0.001) DMI and reduced (P = 0.04) gain:feed and diet NEg content (P = 0.001), but had no effect on ADG (P = 0.20). Feeding 60% DDGS reduced (P < 0.01) DM digestibility as compared with the control. Wheat DDGS has similar feeding value as barley when included at 20% of diet DM, but digestibility and energy content decline with higher levels of inclusion. Key words: Beef, digestibility, distillers' dried grains, wheat

Comprehensive Transcriptome Analyses Reveal Differential Gene Expression Profiles of Camellia sinensis Axillary Buds at Para-, Endo-, Ecodormancy, and Bud Flush Stages

Winter dormancy is an important biological feature for tea plant to survive cold winters, and it also affects the economic output of tea plant, one of the few woody plants in the world whose leaves are harvested and one of the few non-conifer evergreen species with characterized dormancies. To discover the bud dormancy regulation mechanism of tea plant in winter, we analyzed the global gene expression profiles of axillary buds at the paradormancy, endodormancy, ecodormancy, and bud flush stages by RNA-Seq analysis. In total, 16,125 differentially expressed genes (DEGs) were identified among the different measured conditions. Gene set enrichment analysis was performed on the DEGs identified from each dormancy transition. Enriched gene ontology terms, gene sets and transcription factors were mainly associated with epigenetic mechanisms, phytohormone signaling pathways, and callose-related cellular communication regulation. Furthermore, differentially expressed transcription factors as well as chromatin- and phytohormone-associated genes were identified. GI-, CAL-, SVP-, PHYB-, SFR6-, LHY-, ZTL-, PIF4/6-, ABI4-, EIN3-, ETR1-, CCA1-, PIN3-, CDK-, and CO-related gene sets were enriched. Based on sequence homology analysis, we summarized the key genes with significant expression differences in poplar and tea plant. The major molecular pathways involved in tea plant dormancy regulation are consistent with those of poplar to a certain extent; however, the gene expression patterns varied. This study provides the global transcriptome profiles of overwintering buds at different dormancy stages and is meaningful for improving the understanding of bud dormancy in tea plant.

Screening of Chinese medicinal plants for inhibition against clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA)

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional herbs are a valuable source of novel antibacterials in combating pathogenic isolates of methicillin-resistant Staphylococcus aureus (MRSA), a global nosocomial problem.

AIM OF THE STUDY

To assess in vitro anti-MRSA activity of extracts from Chinese herbs. The minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) were determined in the setting of clinical MRSA isolates.

MATERIALS AND METHODS

A collection of 19 plant extracts were obtained and bioassay-guided phytochemical analysis performed. Antibacterial susceptibilities were screened for inhibitory zone and MICs/MBCs determined by serial dilution with a standardized microdilution broth methodology. 9 MRSA isolates and a standard control strain (ATCC 25923) were cultured and exposed to the plant extract and isolated compound. Vancomycin was used as a positive control agent.

RESULTS

All the presented 19 plants showed anti-MRSA activity with MIC of 1.25-3.07mg/ml. The most active antimicrobial plants were Dendrobenthamia capitata, Elsholtzia rugulosa, Elsholtzia blanda, Geranium strictipes and Polygonum multiflorum (MIC< or =1.43mg/ml), and betulinic acid isolated from the active ethyl acetate fraction of Dendrobenthamia capitata extract was determined with MIC/MBC values as 62.5/125.0mg/ml.

CONCLUSIONS

Dendrobenthamia capitata, Elsholtzia rugulosa, Elsholtzia blanda, Geranium strictipesPolygonum multiflorum and betulinic acid demonstrate promising anti-MRSA potential.

Tea plant SWEET transporters: expression profiling, sugar transport, and the involvement of CsSWEET16 in modifying cold tolerance in Arabidopsis

Thirteen SWEET transporters were identified in Camellia sinensis and the cold-suppression gene CsSWEET16 contributed to sugar compartmentation across the vacuole and function in modifying cold tolerance in Arabidopsis. The sugars will eventually be exported transporters (SWEET) family of sugar transporters in plants is a recently identified protein family of sugar uniporters that contain seven transmembrane helices harbouring two MtN3 motifs. SWEETs play important roles in various biological processes, including plant responses to environmental stimuli. In this study, 13 SWEET transporters were identified in Camellia sinensis and were divided into four clades. Transcript abundances of CsSWEET genes were detected in various tissues. CsSWEET1a/1b/2a/2b/2c/3/9b/16/17 were expressed in all of the selected tissues, whereas the expression of CsSWEET5/7/9a/15 was not detected in some tissues, including those of mature leaves. Expression analysis of nine CsSWEET genes in leaves in response to abiotic stresses, natural cold acclimation and Colletotrichum camelliae infection revealed that eight CsSWEET genes responded to abiotic stress, while CsSWEET3 responded to C. camelliae infection. Functional analysis of 13 CsSWEET activities in yeast revealed that CsSWEET1a/1b/7/17 exhibit transport activity for glucose analogues and other types of hexose molecules. Further characterization of the cold-suppression gene CsSWEET16 revealed that this gene is localized in the vacuolar membrane. CsSWEET16 contributed to sugar compartmentation across the vacuole and function in modifying cold tolerance in Arabidopsis. Together, these findings demonstrate that CsSWEET genes play important roles in the response to abiotic and biotic stresses in tea plants and provide insights into the characteristics of SWEET genes in tea plants, which could serve as the basis for further functional identification of such genes.

Greenhouse gas emissions during cattle feedlot manure composting

The emission of greenhouse gases (GHG) during feedlot manure composting reduces the agronomic value of the final compost and increases the greenhouse effect. A study was conducted to determine whether GHG emissions are affected by composting method. Feedlot cattle manure was composted with two aeration methods--passive (no turning) and active (turned six times). Carbon lost in the forms of CO2 and CH4 was 73.8 and 6.3 kg C Mg-1 manure for the passive aeration treatment and 168.0 and 8.1 kg C Mg-1 manure for the active treatment. The N loss in the form of N2O was 0.11 and 0.19 kg N Mg-1 manure for the passive and active treatments. Fuel consumption to turn and maintain the windrow added a further 4.4 kg C Mg-1 manure for the active aeration treatment. Since CH4 and N2O are 21 and 310 times more harmful than CO2 in their global warming effect, the total GHG emission expressed as CO2-C equivalent was 240.2 and 401.4 kg C Mg-1 manure for passive and active aeration. The lower emission associated with the passive treatment was mainly due to the incomplete decomposition of manure and a lower gas diffusion rate. In addition, turning affected N transformation and transport in the window profile, which contributed to higher N2O emissions for the active aeration treatment. Gas diffusion is an important factor controlling GHG emissions. Higher GHG concentrations in compost windrows do not necessarily mean higher production or emission rates.

A comparison of the enzymatic and physicochemical properties of human glutathione transferase M4-4 and three other human Mu class enzymes

The multigene family of cytosolic glutathione S-transferases (GSTs) consists of four classes (Alpha, Mu, Pi, and Theta), all involved in the detoxication of reactive electrophiles. The human Mu class GSTs consist of at least four expressed isozyme subunits, GST M1, GST M2, GST M3, and GST M4, which have 70-90% amino acid sequence identity. The gene and cDNA sequences for GST M4 have been determined recently (K. E. Comstock, K. J. Johnson, D. Rifenbery, and W. D. Henner, J. Biol. Chem. (1993) 268, 16958-16965). Cloning of GST M4 cDNA into an Escherichia coli expression system permitted the production of the corresponding protein. The enzyme was purified and shown to have a relatively low specific activity with the standard GST substrate 1-chloro-2,4-dinitrobenzene (1.4 +/- 0.2 mumol min-1 mg-1 protein), but an activity equivalent to other Mu class enzymes with other tested substrates. The protein forms functional dimers composed of subunits with a M(r) of approximately 26,400. A detailed comparison of the activity with various substrates and inhibitors was performed between GST M4-4 and other human Mu class GSTs, GST M1a-1a, GST M2-2, and GST M3-3, produced in bacterial expression systems. Despite the high level of amino acid sequence identity, the enzymatic properties of these enzymes were quite different. Comparisons with the crystallographic structure of a homologous rat GST, GST 3-3, indicate that a number of the nonconserved amino acid residues can be assigned to the putative active site of GST M4-4. This suggests that diversification in the evolution of these genes has occurred primarily in the substrate binding regions to cope with an increasing variety of foreign compounds.

Metabolic Changes of Caffeine in Tea Plant (Camellia sinensis (L.) O. Kuntze) as Defense Response to Colletotrichum fructicola

Tea plant (Camellia sinensis) is one of the most economically valuable crops in the world. Anthracnose can affect the growth of leaves and cause serious yield losses of tea. Tea plants are rich in secondary metabolites; however, their roles in resistance to anthracnose are unclear. Herein we compared the contents of total phenolics, catechins, and caffeine in two cultivars with different resistances to anthracnose during Colletotrichum fructicola infection. (-)-Epigallocatechin-3-gallate (EGCG), (+)-catechin (C), caffeine, and critical regulatory genes were induced in C. fructicola-resistant tissues. In vitro antifungal tests showed that caffeine more strongly inhibited mycelial growth than tea polyphenols and catechins. Both electron microscopy and bioactivity analysis results showed that caffeine can affect mycelial cell walls and plasma membranes. Through promoter sequences analysis, a number of stress response-related cis-acting elements were identified in S-adenosylmethionine synthetase and tea caffeine synthase. These results demonstrated that (-)-EGCG, (+)-C, and caffeine may be involved in the resistance of tea plants to anthracnose.

Changes in the expression of syndecan-1 in the colorectal adenoma-carcinoma sequence

Syndecan-1, a transmembrane heparan sulphate proteoglycan (HSPG), functions as a matrix receptor on the basal surface of epithelial cells. It also co-localizes with E-cadherin at the lateral cell surface where its function is uncertain. Tumour development in the large bowel is associated with loss of normal epithelial adhesion and altered patterns of expression of cell adhesion molecules, possibly including syndecan-1. To evaluate changes in syndecan-1 expression during the development of colorectal neoplasia, 59 adenomas and 20 carcinomas arising from adenomas were investigated by immunohistochemistry. The staining intensity and distribution of syndecan-1 and E-cadherin in sequential sections was examined, semi-quantified and compared. Staining of syndecan-1 and E-cadherin was uniform in normal colorectal epithelial cells, and located at the basolateral surface. No significant change was seen in either molecule in mildly or moderately dysplastic adenomas. A significant reduction in expression of both syndecan-1 and E-cadherin was seen in severely dysplastic epithelium as compared to moderate dysplasia (P = 0.001 and P = 0.004 respectively). Similarly, there was a significant reduction of both molecules in carcinomas compared with associated adenomas (syndecan-1 P = 0.00003; E-cadherin P = 0.002). In both cases the loss of syndecan-1 expression was more striking than that of E-cadherin. Previous in vitro studies have shown that epithelial cells made deficient in syndecan-1 cease to express E-cadherin, suggesting a causal association. Our results support these findings and indicate that disruption of cell-matrix adhesion is critical in colorectal carcinogenesis, probably preceding changes in the purely homotypic cell-cell adhesion mediated by E-cadherin.

A novel multiscale nonlinear thresholding method for ultrasonic speckle suppressing

This paper presents a novel speckle suppression method for medical B-scan ultrasonic images. An original image is first separated into two parts with an adaptive filter. These two parts are then transformed into a multiscale wavelet domain and the wavelet coefficients are processed by a soft thresholding method, which is a variation of Donoho's soft thresholding method. The processed coefficients for each part are then transformed back into the space domain. Finally, the denoised image is obtained as the sum of the two processed parts. A computer-simulated image and an in vitro B-scan image of a pig heart have been used to test the performance of this new method. This technique effectively reduces the speckle noise, while preserving the resolvable details. It performs well in comparison to the multiscale thresholding technique without adaptive preprocessing and two other speckle-suppression methods.

Abnormal changes of plasma acute phase proteins in schizophrenia and the relation between schizophrenia and haptoglobin (Hp) gene

In this study we focused on detecting schizophrenia related changes of plasma proteins using proteomic technology and examining the relation between schizophrenia and haptoglobin (Hp) genotype. We investigated plasma proteins from schizophrenic subjects (n = 42) and healthy controls (n = 46) by two-dimensional gel electrophoresis (2-DE) in combination with mass spectrometry. To further reveal the genetic relationship between acute phase proteins (APPs) and schizophrenia disease, we tested Hp alpha1/Hp alpha2 (Hp 1/2) polymorphism and two single nucleotide polymorphisms (SNPs) of Hp, rs2070937 and rs5473, for associations with schizophrenia in the Chinese Han population. With the relatively high number of samples for 2-DE work, we found that four proteins in the family of positive APPs were all up-regulated in patients. In genetic association study, we found significant associations existing between schizophrenia and Hp polymorphisms, Hp 1/2 and rs2070937 variants. Schizophrenia is accompanied by both an altered expression of Hp protein and a different genotype distribution of Hp gene, demonstrating that Hp is associated with schizophrenia. The results from proteomic and genomic aspects both indicate that acute phase reaction is likely to be an aetiological agent in the pathophysiology of schizophrenia, but not just an accompanying symptom. The positive APPs are schizophrenic related proteins, with the highly concordant results on four positive APPs.

Acquired resistance to cisplatin and doxorubicin in a small cell lung cancer cell line is correlated to elevated expression of glutathione-linked detoxification enzymes

A human small cell lung cancer cell line, U-1906, developed altered functional properties upon continuous in vitro cultivation. Cells obtained at late (U-1906 L) and early (U-1906 E) passages of cultivation differ in drug resistance to the cytostatic therapeutic agents cisplatin and doxorubicin. The U-1906 L cells are 1.6-fold and 1.3-fold more resistant to cisplatin and doxorubicin respectively, than are the U-1906 E cells. In the more resistant U-1906 L cells, the total glutathione (GSH plus GSSG) level is 40% lower, whereas the activities of GSH-linked enzymes such as GSH peroxidase and GSH transferases are significantly higher. Quantitative analysis with isoenzyme-specific ELISAs demonstrated increased concentrations of all three of the measurable GSTs, M1-1, M3-3 and P1-1, in the more resistant cells. The intracellular protein expression patterns of the U-1906 E and the U-1906 L cells are very similar as revealed by two-dimensional denaturing electrophoresis, but show significant alterations in the concentrations of some components. Two 35 kDa proteins of different pI values, the concentrations of which are increased in the U-1906 L cells, were both identified as glyceraldehyde-3-phosphate dehydrogenase, either by N-terminal or by internal amino acid sequence analysis. The present study demonstrates that the increased resistance of the U-1906 L cells may involve multiple detoxification mechanisms and that the contribution of the GSH-linked detoxification can be ascribed to the elevation of cytosolic GST isoenzymes, GSH peroxidase and glutathione reductase, rather than to the intracellular GSH concentrations.

Imbalance between proliferation and apoptosis in the development of colorectal carcinoma

To evaluate the relationship between cell proliferation and apoptosis in sporadic colorectal carcinogenesis, immunohistochemistry for proliferation-associated antigen Ki-67 and in situ end labelling for identifying apoptotic bodies were performed on paraffin sections from 59 adenomas and 22 carcinomas. These results were correlated with the expression of the proliferation and apoptosis modulators Bcl-2 and p53. Carcinomas showed increased proliferation and apoptosis compared with adenomas (P<0.0001, P<0.001, respectively). There were positive linear correlations between proliferation and apoptosis in adenomas and carcinomas (P<0.02, P<0.05, respectively). The proliferative rate increased significantly from mild to moderate, and from moderate to severe dysplasia (P<0.002, P<0.001, respectively). Apoptotic rate also increased in this sequence, but the increases did not reach statistical significance (both P>0.05). Expression of Bcl-2 was associated with lower apoptotic rate in adenomas (P<0.025) but not in carcinomas (P>0.25), whereas p53 expression was correlated with higher proliferative rate in both adenomas and carcinomas (P<0.01, P<0.05, respectively). An inverse relationship between Bcl-2 and p53 expression was seen in both adenomas and carcinomas (P<0.05, P<0.005, respectively). These data suggest that the normal balance between proliferation and apoptosis is disturbed in colorectal carcinogenesis, both being increased, but proliferation occurs in excess. Bcl-2 and p53 may each play a role in modulating cell apoptosis or proliferation during the development of colorectal carcinoma.