Instrumental Texture Differentiation of Channel (Ictalurus punctatus) and Hybrid (Channel × Blue, Ictalurus furcatus) Catfish Fillets.

An analysis of instrumental texture differences between channel (Ictalurus punctatus) and hybrid (female channel × male blue, I. furcatus) catfish fillets is presented. Factors including cold-storage type (fresh, frozen, or individually quick frozen (IQF)) and gender were included in the comparisons. Texture was measured at eight positions per fillet by a texture profile analysis (TPA) method that provided seven texture attributes: firmness, toughness, cohesiveness, adhesiveness, chewiness, resilience, and springiness, plus the thickness of the fillets (238 total). All attributes except adhesiveness were found to be statistically different (p < 0.05) between channel and hybrid fillets, with channels having the highest value in each attribute. When cold-storage type was included in the analysis, channels still produced the highest attribute values, but the number of attributes differed with firmness, toughness, and chewiness most associated with the differences in the type of catfish, while the other attributes were affected by cold-storage type. Thickness was found to be a strong covariant to some of the texture attributes, especially toughness, but the determination of difference between channels and hybrids was not affected and TPA profiles provided high levels of differentiation between catfish types.

A systematic review and meta-analysis of beta-blockers and renin-angiotensin system inhibitors for preventing left ventricular dysfunction due to anthracyclines or trastuzumab in patients with breast cancer.

AIMS: Trastuzumab and anthracyclines, often used in the treatment of breast cancer, may impair myocardial function, and reduce left ventricular ejection fraction (LVEF), potentially causing heart failure. Randomized controlled trials (RCTs) have evaluated the effects of beta-blockers (BBs), angiotensin receptor blockers (ARBs), and angiotensin-converting enzyme inhibitors (ACEI) on trastuzumab- and anthracycline-associated cardiotoxicity. We report a meta-analysis of these RCTs in patients with breast cancer. METHODS AND RESULTS: The primary analysis was on the effect of BBs and ACEI/ARBs on LVEF in patients treated with either trastuzumab or anthracyclines. A secondary analysis was done investigating the effect of BBs or ACEI/ARBs on LVEF in trastuzumab and anthracycline treatments. Only RCTs were included using the search term 'ARBs, ACEIs, BBs, anthracyclines, trastuzumab, and breast cancer' in PubMed, Embase, and CENTRAL up to 31 March 2021. A meta-analysis was conducted to estimate the mean difference (MD) in LVEF between intervention and placebo groups at follow-up. A total of nine RCTs (n = 1362) were included in the analysis. All patients were women. BBs and ACEI/ARBs were shown to attenuate the decline in LVEF during trastuzumab and anthracycline treatments [MD: 2.4; 95% confidence interval (CI): 0.3-4.2 and MD: 1.5; 95% CI: -0.6 to 3.7]. Compared with placebo, LVEF was significantly higher in patients assigned to BB or ACEI/ARB on trastuzumab (MD: 2.3; 95% CI: 0.0-4.6) but not on anthracyclines (MD: 1.9; 95% CI: -0.5 to 4.2). CONCLUSION: Both BB and ACEI/ARB therapies were associated with the preservation of LVEF during trastuzumab and anthracycline-containing regimens as compared with placebo, suggesting both to be beneficial.

Proximate Composition and Nutritional Attributes of Ready-to-Cook Catfish Products.

To increase the demand for U.S. farm-raised catfish, five healthy, convenient ready-to-cook products were developed to expand consumers' options beyond basic fresh or frozen fillets. Five new catfish products were produced, consisting of one hundred samples of each, including three size-types of Panko-breaded fish products (strips, center cuts of regular fillets, and center cuts from Delacata fillets) and two marinated products (sriracha and sesame-ginger). The breaded products were to be prepared by baking for convenience over traditional frying methods, while the marinated products were to be microwaved as healthy and convenient products. The nutrient content of the samples was analyzed, including protein, moisture, fat, fiber, ash, and carbohydrate, as well as minerals, amino acid, and fatty acid constituent content, with associated atherogenic index (AI) and thrombogenic index (TI), showing unique differences between the Panko-breaded and marinated products. In addition, a trend was observed showing an increase in moisture, protein, ash, and carbohydrate percentages, and a decrease in lipid content related to the volume-to-surface-area ratio, having the order of strips < standard fillets < Delacata fillets.

Properties of bone from Catfish heads and frames.

The objective of this paper was to evaluate methods of producing purified Catfish bone fractions from Catfish frames and heads and determine the composition of the purified bone fraction. Fresh samples of Catfish frames and heads were obtained from a large commercial Catfish processor. Triplicate samples were processed for all treatments. Two methods were developed to remove nonbone tissue from the frames: (a) use of a proteolytic enzyme to digest the nonbone tissues and (b) after boiling the frames, removal of the nonbone tissues with high-pressure water. The ash, protein, and lipid contents of unprocessed dried frames were 17%, 33%, and 41%, respectively. After the enzymatic or high-pressure water treatment processes, the frame bone compositions for the two processes were 62% and 54% ash, 35% and 33% protein, and 9% and 2% lipid, respectively. Bone from both processing treatments had a calcium content of 21%-25%, phosphorus content of 10%-11%, and contents of magnesium, manganese, zinc, and nickel were increased. Hydroxyproline content increased from 4% of the amino acids in the untreated bone to 7%-8% for the processed treatments. Tissues were removed from Catfish heads by digestion with a proteolytic enzyme and collection of the bone with a sieve. After the longest digestion period, dried head bone was 51% ash, 38% protein, and 7% lipid. The amino acid profiles showed high levels of hydroxyproline and lower levels of many essential amino acids. With increased enzymatic hydrolysis time, percent calcium and phosphorus increased. Results from this study will be used in the development of new value-added food and feed ingredients from Catfish bone.

Comparison of sensory and instrumental methods for the analysis of texture of cooked individually quick frozen and fresh-frozen catfish fillets.

Catfish fillet texture is important to consumers, especially if the texture is not what the consumer expects. Therefore, it is important to be able to assure that texture quality is consistent. Texture is a humanly perceived sensory trait and can be costly to processors when texture quality is substandard. Instrumental methods of monitoring texture are much less costly over time than maintaining a sensory quality panel. The purpose of this research was to develop methods for monitoring texture quality using reliable instrumental methods. A descriptive sensory texture panel evaluated fresh-frozen and individually quick frozen (IQF) catfish fillets and was compared to the instrumental analysis of the same cooked fish, using texture profile analysis (TPA). The TPA evaluation was more successful for identifying differences between IQF and fresh-frozen catfish, with the most significance (p < 0.02) seen for the attributes springiness, resilience, chewiness-1, hardness-1, and residual parameters of springiness, chewiness-1, chewiness-1b, and hardness-1b. For sensory evaluation, only moisture release and moisture retention were this significant. Overall, IQF fillets were more moist and cohesive, with fresh-frozen fillets greater in all other parameters. Predictive equations were developed for sensory texture attributes from various TPA attributes calculated from the compression-force curves generated from two compressions of a ball probe. In the fresh-frozen catfish, sensory attributes firmness, flaky, moisture retention, and residual cohesiveness of mass had correlation coefficients (R) of 0.50 or greater. For the IQF catfish, all sensory attributes had an R of less than 0.4. The firmness sensory attribute had TPA predictor variables in both fresh-frozen and IQF that consisted mainly of hardness, chewiness, or thickness-related attributes. Based on results, instrumental texture of catfish should be measured before further processing, such as IQF.

Isolation of Cottonseed Extracts That Affect Human Cancer Cell Growth.

Cottonseeds are classified as glanded or glandless seeds depending on the presence or absence of gossypol glands. Glanded cottonseed has anticancer property and glandless cottonseed was reported to cause cancer in one animal study. It is important to investigate the effect of bioactive components from cottonseeds. Our objectives were to isolate ethanol extracts from cottonseeds and investigate their effects on human cancer cells. A protocol was developed for isolating bioactive extracts from seed coat and kernel of glanded and glandless cottonseeds. HPLC-MS analyzed the four ethanol extracts but only quercetin was identified in the glandless seed coat extract. Residual gossypol was detected in the glanded and glandless seed kernel extracts and but only in the glanded seed coat extract. Ethanol extracts were used to treat human cancer cells derived from breast and pancreas followed by MTT assay for cell viability. Ethanol extracts from glanded and glandless cottonseed kernels and gossypol significantly decreased breast cancer cell mitochondrial activity. Ethanol extract from glanded cottonseed kernel and gossypol also significantly decreased pancreas cancer cell mitochondrial activity. These results suggest that ethanol extracts from cottonseeds, like gossypol, contain anticancer activities.

Effect of Par Frying on Composition and Texture of Breaded and Battered Catfish.

Catfish is often consumed as a breaded and battered fried product; however, there is increasing interest in breaded and battered baked products as a healthier alternative. Par frying can improve the texture properties of breaded and battered baked products, but there are concerns about the increase in lipid uptake from par frying. The objective of this study was to examine the effect of different batters (rice, corn, and wheat) and the effect of par frying on the composition and texture properties of baked catfish. Catfish fillets were cut strips and then coated with batters, which had similar viscosities. Half of the strips were par fried in 177 °C vegetable oil for 1 min and the other half were not par fried. Samples were baked at 177 °C for 25 min. Analysis included % batter adhesion, cooking loss, protein, lipid, ash, and moisture, plus hardness and fracture quality measured using a texture analyzer. A trained sensory panel evaluated both breading and flesh texture attributes. Results found the lipid content of par fried treatments were significantly higher for both corn and wheat batters than for non-par fried treatments. Sensory analysis indicated that the texture of the coatings in the par fried treatments were significantly greater for hardness attributes. Fillet flakiness was significantly greater in the par fried treatments and corn-based batters had moister fillet strips compared to the wheat flour batters. Texture analyzer hardness values were higher for the par fried treatments.

Chemical and nutritional properties of channel and hybrid catfish byproducts.

The objective of this study was to chemically characterize both channel and hybrid catfish parts including heads, frames, viscera, skin, and fillet trimming mince. Triplicate samples of channel and hybrid catfish byproduct parts were obtained from a large commercial catfish processor and analyzed for percent moisture, lipid, protein, ash, and amino acid and fatty acid profiles were determined. The content of the off-flavor compounds, 2-methylisoborneol (MIB) and geosmin were also determined. The lipid content of samples were 13.6% and 10.0% for channel and hybrid skins, 17.7% and 21.4% for channel and hybrid viscera, 20.0% and 19.1% for channel and hybrid frames, and 9.7% and 9.3% for channel and hybrid heads. The protein content of samples ranged from a high of 22.8% for channel catfish skins, to a low of 13.4% for channel frames. Low levels of geosmin, <1 ppb, were detected in the byproduct samples, while no MIB was detected. Palmitic, oleic, and linoleic acid comprised approximately 80% of the fatty acids in the byproduct tissues. The amino acid profiles indicated that the catfish mince had high levels of lysine and methionine and other essential amino acids. Results from this study will be used in the development of new value-added products from catfish byproducts.

Effect of precooking and polyphosphate treatment on the quality of microwave cooked catfish fillets.

In the U.S. market place, there are many examples of precooked poultry products designed to be reheated in a microwave oven and, to a lesser extent, fish products such as tilapia. However, few U.S. catfish products are designed to be microwave cooked or reheated. The first objective of this study was to examine the properties of microwave cooked raw frozen catfish fillets and oven precooked (to 62.8°C) frozen fillets and then reheated by microwave cooking. The second objective was to evaluate changes in properties as a consequence of treatment with a commercial polyphosphate blend (Individually Quick Frozen [IQF]). The sample analysis included weight loss, proximate content, color (CIE L*a*b*), pH, mechanical texture (hardness), and lipid peroxidation (TBARS) measurements. Frozen fillets which contained polyphosphate showed <4% moisture loss after microwave cooking, relative to a 12% moisture loss for fillets without polyphosphate. A large cooking loss of ~40% was observed for precooked fillets after microwave cooking, correlated with a higher percent moisture loss (11% and 13% for fillets with and without polyphosphate, respectively) to comparable samples that were not precooked. For both types of fillets, an increased amount of yellow color was observed for precooked fillets after microwave cooking, relative to comparable fillets that were not precooked. Fillet hardness determined by peak force revealed an overall harder texture (~1.1-1.8 times) for fillets without polyphosphate than fillets with polyphosphate. This study will be used to develop precooked catfish products that can be reheated in a microwave oven.

RNA-Seq Analysis of Developing Pecan (Carya illinoinensis) Embryos Reveals Parallel Expression Patterns among Allergen and Lipid Metabolism Genes.

The pecan nut is a nutrient-rich part of a healthy diet full of beneficial fatty acids and antioxidants, but can also cause allergic reactions in people suffering from food allergy to the nuts. The transcriptome of a developing pecan nut was characterized to identify the gene expression occurring during the process of nut development and to highlight those genes involved in fatty acid metabolism and those that commonly act as food allergens. Pecan samples were collected at several time points during the embryo development process including the water, gel, dough, and mature nut stages. Library preparation and sequencing were performed using Illumina-based mRNA HiSeq with RNA from four time points during the growing season during August and September 2012. Sequence analysis with Trinotate software following the Trinity protocol identified 133,000 unigenes with 52,267 named transcripts and 45,882 annotated genes. A total of 27,312 genes were defined by GO annotation. Gene expression clustering analysis identified 12 different gene expression profiles, each containing a number of genes. Three pecan seed storage proteins that commonly act as allergens, Car i 1, Car i 2, and Car i 4, were significantly up-regulated during the time course. Up-regulated fatty acid metabolism genes that were identified included acyl-[ACP] desaturase and omega-6 desaturase genes involved in oleic and linoleic acid metabolism. Notably, a few of the up-regulated acyl-[ACP] desaturase and omega-6 desaturase genes that were identified have expression patterns similar to the allergen genes based upon gene expression clustering and qPCR analysis. These findings suggest the possibility of coordinated accumulation of lipids and allergens during pecan nut embryogenesis.

The effectiveness of payment for performance in health care: A meta-analysis and exploration of variation in outcomes.

BACKGROUND: Pay for performance (P4P) incentive schemes are increasingly used world-wide to improve health system performance but results of evaluations vary considerably. A systematic analysis of this variation in the effects of P4P schemes is needed. METHODS: Evaluations of P4P schemes from any country were identified by searching for and updating systematic reviews of P4P schemes in health care in four bibliographic databases. Outcomes using different measures of effect were converted into standardized effect sizes (standardized mean difference, SMD) and each study was categorized as to whether or not it found a positive effect. Subgroup analysis, meta-regression and multilevel logistic regression were used to investigate factors explaining heterogeneity. Random-effects models were used because they take into account heterogeneity likely to be due to differences between studies rather than just chance. Sensitivity analysis was used to test the effect of different assumptions. FINDINGS: 96 primary studies were identified; 37 were included in the meta-analysis and meta-regression and all 96 in the logistic regression. The proportion of observed variation in study results that can be explained by true heterogeneity (I2) was 99.9%. Estimates of effect of P4P schemes were lower in evaluations using randomized controlled trials (SMD=0.08; 95% CI: 0.01-0.15) compared to no controls (0.15; 95% CI: 0.09-0.21), and lower for those measuring outcomes (e.g., smoking cessation) (SMD=0.0; 95% CI: -0.01 to 0.01) compared to process measures (e.g., giving cessation advice) (0.18; 95% CI: 0.06-0.31). Adjusting for other design features and the evaluation method, the odds of showing a positive effect was three times higher for schemes with larger incentives (>5% of salary/usual budget) (OR=3.38; 95% CI: 1.07-10.64). There were non-statistically significant increases in the odds of success if the incentive is paid to individuals (as opposed to groups) (OR=2.0; 95% CI: 0.62-6.56) and if there is a lower perceived risk of not earning the incentive (OR=2.9; 95% CI: 0.78-10.83). Schemes evaluated using less rigorous designs were 24 times more likely to have positive estimates of effect than those using randomized controlled trials (OR=24; 95% CI: 6.3-92.8). INTERPRETATION: Estimates of the effectiveness of incentive schemes on health outcomes are probably inflated due to poorly designed evaluations and a focus on process measures rather than health outcomes. Larger incentives and reducing the perceived risk of non-payment may increase the effect of these schemes on provider behavior.

RNA sequencing of an nsdC mutant reveals global regulation of secondary metabolic gene clusters in Aspergillus flavus.

The filamentous fungus, Aspergillus flavus (A. flavus) is an opportunistic pathogen capable of invading a number of crops and contaminating them with toxic secondary metabolites such as aflatoxins. Characterizing the molecular mechanisms governing growth and development of this organism is vital for developing safe and effective strategies for reducing crop contamination. The transcription factor nsdC has been identified as being required for normal asexual development and aflatoxin production in A. flavus. Building on a previous study using a large (L)-sclerotial morphotype A. flavus nsdC mutant we observed alterations in conidiophore development and loss of sclerotial and aflatoxin production using a nsdC mutant of a small (S)-sclerotial morphotype, that normally produces aflatoxin and sclerotia in quantities much higher than the L-morphotype. RNA sequencing analysis of the nsdC knockout mutant and isogenic control strain identified a number of differentially expressed genes related to development and production of secondary metabolites, including aflatoxin, penicillin and aflatrem. Further, RNA-seq data indicating down regulation of aflatrem biosynthetic gene expression in the nsdC mutant correlated with HPLC analyses showing a decrease in aflatrem levels. The current study expands the role of nsdC as a globally acting transcription factor that is a critical regulator of both asexual reproduction and secondary metabolism in A. flavus.

A systematic review on drugs absorption modifications after eradication in Helicobacter pylori positive patients undergoing replacement therapy.

BACKGROUND AND AIMS: Helicobacter pylori (H. pylori) infection has been suggested as a cause of impaired drug absorption. This infection leads to alteration of the gastric acid secretion that may change the conformational characteristics of drugs and their intestinal absorption leading to uncertainties about the dose to administer and the therapeutic results. A systematic review was undertaken to clarify the implications of drug absorption during the administration of replacement therapies. METHODS: Electronic databases such as MEDLINE/Pubmed, EMBASE and The Cochrane Library [which includes Cochrane Database of Systematic Review (CDSR), the Cochrane Central Register of Controlled Trials (CENTRAL), the Database of Abstract of Reviews of Effect (DARE)] were searched. Grey literature databases (e.g. the International clinical trials registry platform, Trials Register, Clinical Trials.gov, Controlled Trials and TrialsCentral), Theses database, Government publication and LILACS database were also searched. No language restriction was applied. RESULTS: Infection and altered drug absorption were evaluated in patients under replacement therapies with iron, thyroxin and L-dopa. In all, seven studies included an improvement in drug absorption after eradication and an existing inverse correlation between the grade of gastric inflammation and indices of drug absorption were noticed. CONCLUSION: This systematic review confirmed the presence of an interaction between infection and drug absorption of orally administered replacement therapies. Gastric acid reduction and subsequent alteration of drug composition seem to lead this mechanism. Clinicians should be aware of this possible interaction when starting a replacement therapy in patients and when evaluating poor clinical response.

Exercise-based cardiac rehabilitation in patients with heart failure: a meta-analysis of randomised controlled trials between 1999 and 2013.

BACKGROUND: Guidelines recommend exercise-based cardiac rehabilitation (EBCR) for patients with heart failure (HF). However, established research has not investigated the longer-term outcomes including mortality and hospitalisation in light of the contemporary management of HF. METHODS: This was a systematic review including a meta-analysis of EBCR on all-cause mortality, hospital admission, and standardised exercise capacity using four separate exercise tests in patients with heart failure over a minimum follow-up of six months from January 1999-January 2013. Electronic searches were performed in the databases: Medline, CENTRAL, EMBASE, CINAHL, and PsycINFO constrained to randomised controlled trials (RCTs). RESULTS: A total of 46 separate RCTs qualified for the meta-analysis, which employed conventional methods for binary and continuous data. The relative risk (RR) ratio for hospital admission (12 studies) was significantly reduced (RR ratio 0.65; 95% confidence interval (CI) 0.50-0.84; p = 0.001), but mortality (21 studies) was not (RR ratio 0.88; 95% CI 0.77-1.02; p = 0.08). The standardised exercise capacity (26 studies) showed a standardised mean difference (SMD) in favour of the exercise group as compared with the controls (SMD 0.98, 95% CI 0.59-1.37; p < 0.001). Women and elderly people were less frequently enrolled in the RCTs independent of the outcomes. Heterogeneity was moderate to high in the analysis of hospital admission and the standardised exercise capacity demonstrated through skewedness in their funnel plots. CONCLUSIONS: EBCR in patients with HF is associated with significant improvements in exercise capacity and hospital admission over a minimum of six months follow-up, but not in all-cause mortality.

Impact of aspirin and statins on long-term survival in patients hospitalized with acute myocardial infarction complicated by heart failure: an analysis of 1706 patients.

AIMS: Aspirin and statins are established therapies for acute myocardial infarction (MI), but their benefits in patients with chronic heart failure (HF) remain elusive. We investigated the impact of aspirin and statins on long-term survival in patients hospitalized with acute MI complicated by HF. METHODS AND RESULTS: Of 4251 patients in the Evaluation of Methods and Management of Acute Coronary Events (EMMACE)-1 and -2 observational studies, 1706 patients had HF. A propensity score-matching method estimated the average treatment effects (ATEs) of aspirin and statins on survival over 90 months. ATEs were calculated as relative risk differences in all-cause mortality comparing patients receiving aspirin and statins with controls, respectively. Moreover, combined aspirin and statins vs. none (ATE I), aspirin or statins vs. none (ATE II), and aspirin and statins vs. aspirin or statins (ATE III) were assessed. The median survival times of the ATE I, ATE II and ATE III were 25, 50, and 85 months, respectively. Regarding aspirin, the ATE was significantly improved at 6, 12, and 90 months [ATE 6 months: 10%, 95% confidence interval (CI) 3-18%], where the ATE of statins favoured survival at 1-24 months (ATE 1 month: 5%, 95% CI 0.3-10%). Mortality was lower at 1, 6, and 24 months in those who received aspirin and statins (ATE I). When the combination was compared with either treatment alone, an effect persisted between 6 and 90 months (ATE III). CONCLUSION: In patients with acute MI complicated by HF, prescription of aspirin and statins either alone or together was associated with better long-term survival.

The effect of referral for cardiac rehabilitation on survival following acute myocardial infarction: a comparison survival in two cohorts collected in 1995 and 2003.

BACKGROUND: International guidelines recommend referral for cardiac rehabilitation (CR) after acute myocardial infarction (AMI). However, the impact on long-term survival after CR referral has not been adjusted by time-variance. We compared the effects of CR referral after hospitalization for AMI in two consecutive decades. METHODS AND RESULTS: A total of 2196 and 2055 patients were recruited in the prospective observational studies of the Evaluation of the Methods and Management of Acute Coronary Events (EMMACE) -1 and 2 in 1995 and 2003, (1995: median age 72 years, 39% women, 74% referred vs 2003: median age 71 years, 36% women, 64% referred) and followed up through September 2010. Survival functions showed CR referral to be an independent predictor for survival in 2003, but not in 1995 (hazard ratio (HR), 0.90; 95% confidence interval [CI]; 0.70 to 1.17, p = 0.44 in 1995 vs HR, 0.80; 95% CI, 0.66 to 0.96, p = 0.02 in 2003) when patients entered the model at three months after discharge and had a common exit at 90 months. Significant positive and negative predictors for CR referral were beta-blocker prescription (+), reperfusion (+) and age (-) in 1995, and reperfusion (+), revascularization (+), heart failure (HF) (+), antiplatelets (+), angiotensin-converting-enzyme inhibitor (ACE-I) (+), statins (+), diabetes (-), and the modified Global Registry of Acute Cardiac Events (GRACE) risk score (-) in 2003. CONCLUSIONS: CR referral was associated with improved survival in 2003, but not in 1995 in patients admitted with acute MI.

A transcript profiling approach reveals an abscisic acid-specific glycosyltransferase (UGT73C14) induced in developing fiber of Ligon lintless-2 mutant of cotton (Gossypium hirsutum L.).

Ligon lintless-2, a monogenic dominant cotton (Gossypium hirsutum L.) fiber mutation, causing extreme reduction in lint fiber length with no pleiotropic effects on vegetative growth, represents an excellent model system to study fiber elongation. A UDP-glycosyltransferase that was highly expressed in developing fibers of the mutant Ligon lintless-2 was isolated. The predicted amino acid sequence showed ~53% similarity with Arabidopsis UGT73C sub-family members and the UDP-glycosyltransferase was designated as UGT73C14. When expressed in Escherichia coli as a recombinant protein with a maltose binding protein tag, UGT73C14 displayed enzymatic activity toward ABA and utilized UDP-glucose and UDP-galactose as the sugar donors. The recombinant UGT73C14 converted natural occurring isoform (+)-cis, trans-ABA better than (+)-trans, trans-ABA and (-)-cis, trans-ABA. Transgenic Arabidopsis plants constitutively overexpressing UGT73C14 did not show phenotypic changes under standard growth conditions. However, the increased glycosylation of ABA resulted in phenotypic changes in post-germinative growth and seedling establishment, confirming in vivo activity of UGT73C14 for ABA. This suggests that the expression level of UGT73C14 is regulated by the observed elevated levels of ABA in developing fibers of the Li 2 mutant line and may be involved in the regulation of ABA homeostasis.

Integrated metabolomics and genomics analysis provides new insights into the fiber elongation process in Ligon lintless-2 mutant cotton (Gossypium hirsutum L.).

BACKGROUND: The length of cotton fiber is an important agronomic trait characteristic that directly affects the quality of yarn and fabric. The cotton (Gossypium hirsutum L.) fiber mutation, Ligon lintless-2, is controlled by a single dominant gene (Li(2)) and results in extremely shortened lint fibers on mature seeds with no visible pleiotropic effects on vegetative growth and development. The Li(2) mutant phenotype provides an ideal model system to study fiber elongation. To understand metabolic processes involved in cotton fiber elongation, changes in metabolites and transcripts in the Li(2) mutant fibers were compared to wild-type fibers during development. RESULTS: Principal component analysis of metabolites from GC-MS data separated Li(2) mutant fiber samples from WT fiber samples at the WT elongation stage, indicating that the Li(2) mutation altered the metabolome of the mutant fibers. The observed alterations in the Li(2) metabolome included significant reductions in the levels of detected free sugars, sugar alcohols, sugar acids, and sugar phosphates. Biological processes associated with carbohydrate biosynthesis, cell wall loosening, and cytoskeleton were also down-regulated in Li(2) fibers. Gamma-aminobutyric acid, known as a signaling factor in many organisms, was significantly elevated in mutant fibers. Higher accumulation of 2-ketoglutarate, succinate, and malate suggested higher nitrate assimilation in the Li(2) line. Transcriptional activation of genes involved in nitrogen compound metabolism along with changes in the levels of nitrogen transport amino acids suggested re-direction of carbon flow into nitrogen metabolism in Li(2) mutant fibers. CONCLUSIONS: This report provides the first comprehensive analysis of metabolite and transcript changes in response to the Li(2) mutation in elongating fibers. A number of factors associated with cell elongation found in this study will facilitate further research in understanding metabolic processes of cotton fiber elongation.

Characterization of a new endogenous endo-ß-1,4-glucanase of Formosan subterranean termite (Coptotermes formosanus).

The present work characterized a new endogenous cellulase (endo-ß-1,4-glucanase) gene, CfEG5, uncovered in the transcriptome of Formosan subterranean termite (Coptotermes formosanus). The full-length gene was cloned and sequenced. It is similar to the CfEG3a described earlier (Zhang et al., 2009) but not likely an allelic variant. GenomeWalker™ DNA walking analysis indicated that there may be one copy of CfEG5 and two copies of CfEG3a in the termite genome. As with CfEG3a, the transcript of CfEG5 was detected predominantly in the salivary gland based on quantitative RT-PCR. Phylogenetic analysis of translated amino acid sequence showed that the CfEG5 is more related to CaEG, derived from an Australian subterranean termite (Coptotermes acinaciformis), than CfEG3a and other cellulases from Coptotermes formosanus, Reticulitermes speratus, or Reticulitermes flavipes. Recombinant CfEG5, produced in Escherichia coli, was active against filter-paper cellulose, resulting in mostly cellobiose and cellotriose, similar to the enzymatic and biochemical properties of CfEG3a. These findings would lead to further investigation of both the evolutionary origin of eukaryotic cellulase genes and the evolutionary relationship of termite species. The cellulose-degrading enzyme is applicable for bioconversion of wood to simple sugars and production of biofuels. The recombinant cellulase should also be useful for designing and screening of inhibitors for the development of target-specific and environment-friendly bio-termicides.