Function of the pseudo phosphotransfer proteins has diverged between rice and Arabidopsis

The phytohormone cytokinin plays a significant role in nearly all aspects of plant growth and development. Cytokinin signaling has primarily been studied in the dicot model Arabidopsis, with relatively little work done in monocots, which include rice (Oryza sativa) and other cereals of agronomic importance. The cytokinin signaling pathway is a phosphorelay comprised of the histidine kinase receptors, the authentic histidine phosphotransfer proteins (AHPs) and type-B response regulators (RRs). Two negative regulators of cytokinin signaling have been identified: the type-A RRs, which are cytokinin primary response genes, and the pseudo histidine phosphotransfer proteins (PHPs), which lack the His residue required for phosphorelay. Here, we describe the role of the rice PHP genes. Phylogenic analysis indicates that the PHPs are generally first found in the genomes of gymnosperms and that they arose independently in monocots and dicots. Consistent with this, the three rice PHPs fail to complement an Arabidopsis php mutant (aphp1/ahp6). Disruption of the three rice PHPs results in a molecular phenotype consistent with these elements acting as negative regulators of cytokinin signaling, including the induction of a number of type-A RR and cytokinin oxidase genes. The triple php mutant affects multiple aspects of rice growth and development, including shoot morphology, panicle architecture, and seed fill. In contrast to Arabidopsis, disruption of the rice PHPs does not affect root vascular patterning, suggesting that while many aspects of key signaling networks are conserved between monocots and dicots, the roles of at least some cytokinin signaling elements are distinct.     

Population structure in sorghum accessions from West Africa differing in race and maturity class

Accounting for population structure to minimize spurious associations in association analyses is of crucial importance. With sorghum genomic sequence information being available, there is a growing interest in performing such association studies for a number of important agronomic traits using a candidate gene approach. The aims of our study were to conduct a systematic survey of molecular genetic diversity and analyze the population structure in cultivated sorghum [Sorghum bicolor (L.) Moench] accessions from West Africa. Our analysis included 219 West African cultivated sorghum accessions with differing maturity intended for a marker-trait association study. A total of 27 SSRs were used, which resulted in detection of 513 alleles. Genetic diversity estimates for the accessions were found to be high. The accessions were divided into two subgroups using a model-based approach. Our findings partly agree with previous studies in that the guinea race accessions could be distinguished clearly from other accessions included in the analysis. Race and geographical origin of the accessions may be responsible for the structure we observed in our material. The extent of linkage disequilibrium for all combinations of SSRs was in agreement with expectations based on the mating system.     

Evaluation of codA,tms2, and ABRIN-A as negative selectable markers in transgenic tobacco and rice

The codA and tms2 genes are used as efficient conditional negative selectable markers (NSMs) in several dicotyledonous plants. We evaluated both genes under control of the CaMV 35S promoter for their effectiveness as conditional NSMs. The ABRIN-A chain gene from Abrus precatorius was evaluated as a nonconditional NSM. The efficacies of codA, tms2, and ABRIN-A as NSMs were compared in transgenic rice and tobacco. Tobacco leaf discs and scutellum-derived callus of rice were transformed with the three genes. Leaf discs of T₀ transgenic tobacco plants and the T₁ seedlings of transgenic rice plants, both transformed with codA, showed a pronounced reduction in growth in the presence of the substrate 5-fluorocytosine. The tms2 gene was inferred to act as a nonconditional NSM in tobacco since all the recovered hygromycin-resistant transgenic tobacco plants harbored only truncated transferred DNAs (T-DNAs) with deletions of the tms2 gene. The T₁ transgenic rice seedlings transformed with tms2 showed a drastic reduction in shoot and root growth in the presence of the substrate naphthaleneacetamide. Both codA and tms2 genes served as good conditional NSMs in rice. The ABRIN-A gene proved to be a good nonconditional NSM in tobacco since all recovered hygromycin-resistant plants harbored only truncated T-DNAs with deletions of the ABRIN-A gene. Twelve transgenic rice plants, which harbored the complete ABRIN-A gene, displayed normal growth suggesting that ABRIN-A is not toxic to rice.     

Markers of intestinal inflammation in patients with ankylosing spondylitis: a pilot study

Introduction

Inflammatory bowel disease (IBD) and ankylosing spondylitis (AS) are similar chronic inflammatory diseases whose definitive etiology is unknown. Following recent clinical and genetic evidence supporting an intertwined pathogenic relationship, we conducted a pilot study to measure fecal calprotectin (fCAL) and IBD-related serologies in AS patients.

Methods

Consecutive AS patients were recruited from a long-term prospectively collected longitudinal AS cohort at Cedars-Sinai Medical Center. Controls were recruited from Cedars-Sinai Medical Center employees or spouses of patients with AS. Sera were tested by ELISA for IBD-associated serologies (antineutrophil cytoplasmic antibodies (ANCA), anti-Saccharomyces cerevisiae antibody IgG and IgA, anti-I2, anti-OmpC, and anti-CBir1). The Bath Ankylosing Spondylitis Disease Activity Index, the Bath Ankylosing Spondylitis Functional Index, and the Bath Ankylosing Spondylitis Radiology Index were completed for AS patients.

Results

A total of 81 subjects (39 AS patients and 42 controls) were included for analysis. The average age of AS patients was 47 years and the average disease duration was 22 years. AS patients were predominantly male; 76% were HLA-B27-positive. Median fCAL levels were 42 μg/g and 17 μg/g in the AS group and controls, respectively (P < 0.001). When using the manufacturer''s recommended cutoff value for positivity of 50 μg/g, stool samples of 41% of AS patients and 10% of controls were positive for fCAL (P = 0.0016). With the exception of ANCA, there were no significant differences in antibody levels between patients and controls. Median ANCA was 6.9 ELISA units in AS patients and 4.3 ELISA units in the controls. Among AS patients stratified by fCAL level, there were statistically significant differences between patients and controls for multiple IBD-associated antibodies.

Conclusion

Calprotectin levels were elevated in 41% of patients with AS with a cutoff value for positivity of 50 μg/g. fCAL-positive AS patients displayed higher medians of most IBD-specific antibodies when compared with healthy controls or fCAL-negative AS patients. Further studies are needed to determine whether fCAL can be used to identify and characterize a subgroup of AS patients whose disease might be driven by subclinical bowel inflammation.     

Production of Deuterated Lutein by Chlorella protothecoides and its Detection by Mass Spectrometric Methods

Chlorella protothecoides, a lutein-producing microalga, was grown aerobically in a mineral medium prepared with 70% (v/v) deuterated water. HPLC/atmospheric pressure chemical ionization-mass spectrometry (HPLC/APCI-MS) analysis revealed 58% replacement of hydrogen by deuterium atoms as indicated by the molecular mass cluster at around m/z 599. The rapidly growing microalga had much higher levels (58%) of deuterium substitution relative to previously reported (9–15%) natural sources of lutein.     

Synthesis,antidepressant evaluation and QSAR studies of novel 2-(5H-[1,2,4]triazino[5,6-b]indol-3-ylthio)-N-(substituted phenyl)acetamides

In search for novel antidepressants, a series of 2-(5H-[1,2,4]triazino[5,6-b]indol-3-ylthio)-N-(substituted phenyl)acetamides was synthesized and screened for potential antidepressant activity by tail suspension test (TST) in mice. Number of synthesized compounds exhibited impressive antidepressant activity, measured in terms of percentage decrease in immobility duration (%DID). QSAR analysis was also undertaken which correlated three parameters FOSA, PISA, and glob with biological activity.     

Prevalence and Predictors of Colposcopic-Histopathologically Confirmed Cervical Intraepithelial Neoplasia in HIV-Infected Women in India

Background

Prevalence estimates of cervical intraepithelial neoplasia (CIN) among HIV-infected women in India have been based on cervical cytology, which may have underestimated true disease burden. We sought to better establish prevalence estimates and evaluate risk factors of CIN among HIV-infected women in Pune, India using colposcopy and histopathology as diagnostic tools.

Methodology

Previously unscreened, non-pregnant HIV-infected women underwent cervical cancer screening evaluation including standardized diagnostic colposcopy by a gynecologist. Histopathologic confirmation was conducted among consenting women with clinical suspicion of CIN. The prevalence of CIN was evaluated by a composite diagnosis based on colposcopy and histopathology results. Multivariable ordinal logistic regression analysis was conducted to determine independent predictors of increasing severity of CIN.

Results

The median age of the n = 303 enrolled HIV-infected women was 30 years (interquartile range, 27–34). A majority of the participants were widowed or separated (187/303, 61.7%), more than one-third (114/302, 37.7%) were not educated beyond primary school, and nearly two-thirds (196/301, 64.7%) had a family per capita income of <1,000 Indian Rupees (∼US$22) per month. Cervical high-risk HPV-DNA was detected in 41.7% (124/297) of participants. The composite colposcopic-histopathologic diagnoses revealed no evidence of CIN in 220 out of 303 (72.6%) women, CIN1 in 33/303 (10.9%), CIN2 in 31/303 (10.2%), CIN3 in 18/303 (5.9%) and 1 (0.3%) woman was diagnosed with ICC. Thus, over a quarter of the participants [83/303: 27.7% (95% CI: 22.7–33.1)] had ≥CIN1 lesions and a sixth [50/303: 16.5% (95% CI: 12.2–21.9)] had evidence of advanced (≥CIN2) neoplastic disease. The independent predictors of increasing severity of CIN as revealed by a proportional odds model using multivariable ordinal logistic regression included (i) currently receiving antiretroviral therapy [adjusted odds ratios (aOR): 2.24 (1.17, 4.26), p = 0.01] and (ii) presence of cervical high-risk HPV-DNA [aOR: 1.93 (1.13, 3.28), p = 0.02].

Conclusions

HIV-infected women in Pune, India have a substantial burden of cervical precancerous lesions, which may progress to invasive cervical cancer unless appropriately detected and treated. Increased attention should focus on recognizing and addressing this entirely preventable cancer among HIV-infected women, especially in the context of increasing longevity due to antiretroviral therapy.     

Relationship of HMW, LMW Glutenin Subunits and γ-gliadins with Gluten Strength in Indian Durum Wheats

Twenty-four durum wheat genotypes were evaluated for two years to assess the relationship between HMWglutenin subunits, LMWB glutenin patterns, gammagliadins and gluten strength as measured by SDS-sedimentation volume. Indian durum genotypes assessed in this study represented a diverse set of Glu-1, GH-B1 and Glu-3 alleles. Considerable variability was detected for protein content and gluten strength. All the locals and released varieties derived from locals showed significantly higher protein content. Specific alleles at Glu-1, Glu-3 and Gli-B1 loci showed different effects on gluten strength. HMW glutenin subunits 2^* and 14+15 showed association with high gluten strength. Genotypes having LMW-f (linked γ-43.5) showed significantly higher gluten strength than other three LMW-B patterns, i.e. LMW-b and c (linked γ-45) and LMW-e(linked γ-44). While genotypes with γ-44 and linked LMW-e patterns were found to have lowest gluten strength. The Gli-A2 locus did not show any significant association with gluten strength.     

Factorial analysis of tricarboxylic acid cycle intermediates for optimization of zeaxanthin production from Flavobacterium multivorum

AIMS: To study the effect of intermediates of the tricarboxylic acid (TCA) cycle on the production of zeaxanthin from Flavobacterium multivorum in order to optimize production of this xanthophyll carotenoid. METHODS AND RESULTS: The concentration of selected TCA cycle intermediates (malic acid, isocitric acid and alpha-ketoglutarate) was optimized in shake flask culture, using a statistical two-level, three-variable factorial approach. The carotenoid production profile was also studied in the optimized medium at various growth phases. Optimized medium resulted in a sixfold increase in volumetric production of zeaxanthin (10.65 +/- 0.63 microg ml-1) using malic acid (6.02 mm), isocitric acid (6.20 mm) and alpha-ketoglutarate (0.02 mm). The majority of zeaxanthin was produced in the late logarithmic growth phase whereas a substantial amount of beta-cryptoxanthin and beta-carotene were observed in the early logarithmic phase. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates improvement of zeaxanthin production from F. multivorum which might aid in the commercialization of zeaxanthin production from this microbe.