Multiple factors contribute to outcrossing in a tropical emergent Dipterocarpus tempehes, including a new pollen-tube guidance mechanism for self-incompatibility

The self-rejection system of Dipterocarpus tempehes (Dipterocarpaceae), an emergent tree of the lowland tropical forests of Borneo, were studied by means of pollination experiments, fluorescence microscopy of pollen tubes, and monitoring of ovary maturation patterns. Fruit set was higher in cross-pollinated flowers than in control and self-pollinated flowers, indicating the existence of pollen limitation and a self-rejection system. Although the adhesion and the germination of self-pollen and the growth of self-pollen tubes were not inhibited, the proportion of cross-pollen tubes that entered the style was 1.7-2.3 times higher than that of self-pollen tubes, indicating a partial self-incompatibility that inhibits self-pollen tubes from entering the style hollow. These results suggest, for the first time, that self-incompatibility is caused by a defect of pollen-tube guidance. We also suggest a threshold effect in number of pollen tubes or late-acting self-incompatibility to fully explain the drastic and uniform selection against self-pollinated flowers before ovary swelling. After that, maternal selection and/or inbreeding depression caused the abortion and delayed maturation of self-pollinated flowers. The advantages of the self-rejection process composed of partial early-acting self-incompatibility and relatively strong delayed abortion is discussed with respect to the general-flowering phenomenon in lowland dipterocarp forests.     

A genetic linkage map of water yam ( Dioscorea alata L.) based on AFLP markers and QTL analysis for anthracnose resistance

A genetic linkage map of the tetraploid water yam (Dioscorea alata L.) genome was constructed based on 469 co-dominantly scored amplified fragment length polymorphism (AFLP) markers segregating in an intraspecific F₁ cross. The F₁ was obtained by crossing two improved breeding lines, TDa 95/00328 as female parent and TDa 87/01091 as male parent. Since the mapping population was an F₁ cross between presumed heterozygous parents, marker segregation data from both parents were initially split into maternal and paternal data sets, and separate genetic linkage maps were constructed. Later, data analysis showed that this was not necessary and thus the combined markers from both parents were used to construct a genetic linkage map. The 469 markers were mapped on 20 linkage groups with a total map length of 1,233 cM and a mean marker spacing of 2.62 cM. The markers segregated like a diploid cross-pollinator population suggesting that the water yam genome is allo-tetraploid (2n = 4x = 40). QTL mapping revealed one AFLP marker E-14/M52-307 located on linkage group 2 that was associated with anthracnose resistance, explaining 10% of the total phenotypic variance. This map covers 65% of the yam genome and is the first linkage map reported for D. alata. The map provides a tool for further genetic analysis of traits of agronomic importance and for using marker-assisted selection in D. alata breeding programmes. QTL mapping opens new avenues for accumulating anthracnose resistance genes in preferred D. alata cultivars.     

Production of an amylase-degrading raw starch by Gibberella pulicaris

An endophytic fungus, Gibberella pulicaris, produced an amylase which degraded raw starches from cereals and other crops including raw potato, sago, tapioca, corn, wheat and rice starch. In each case, glucose was the main product. Among the raw starches used, raw potato starch gave the highest enzyme activity (85 units mg^–1 protein) and raw wheat starch the lowest (49 units mg^–1 protein). The highest amylase production (260 units mg^–1 protein) was achieved when the concentration of raw potato starch was increased to 60 g l^–1. Optimum hydrolysis was at 40°C and pH 5.5.     

Redox State and Mitochondrial Respiratory Chain Function in Skeletal Muscle of LGMD2A Patients

Background

Calpain-3 deficiency causes oxidative and nitrosative stress-induced damage in skeletal muscle of LGMD2A patients, but mitochondrial respiratory chain function and anti-oxidant levels have not been systematically assessed in this clinical population previously.

Methods

We identified 14 patients with phenotypes consistent with LGMD2A and performed CAPN3 gene sequencing, CAPN3 expression/autolysis measurements, and in silico predictions of pathogenicity. Oxidative damage, anti-oxidant capacity, and mitochondrial enzyme activities were determined in a subset of muscle biopsies.

Results

Twenty-one disease-causing variants were detected along the entire CAPN3 gene, five of which were novel (c.338 T>C, c.500 T>C, c.1525-1 G>T, c.2115+4 T>G, c.2366 T>A). Protein- and mRNA-based tests confirmed in silico predictions and the clinical diagnosis in 75% of patients. Reductions in antioxidant defense mechanisms (SOD-1 and NRF-2, but not SOD-2), coupled with increased lipid peroxidation and protein ubiquitination, were observed in calpain-3 deficient muscle, indicating a redox imbalance primarily affecting non-mitochondrial compartments. Although ATP synthase levels were significantly lower in LGMD2A patients, citrate synthase, cytochrome c oxidase, and complex I+III activities were not different from controls.

Conclusions

Despite significant oxidative damage and redox imbalance in cytosolic/myofibrillar compartments, mitochondrial respiratory chain function is largely maintained in skeletal muscle of LGMD2A patients.     

Prevalence,Associated Factors and Predictors of Depression among Adults in the Community of Selangor,Malaysia

Introduction

Depression is one of the most common mental health disorders and is an emerging public health problem. The objectives of this paper were to determine the prevalence of depression, its associated factors and the predictors of depression among adults in the community of Selangor.

Methods

A cross sectional study was conducted in three districts in Selangor, from 11th June to 30th December 2012. The sampling frame was obtained from the Department of Statistics Malaysia (DOS) in May 2012, using the National Population and Housing Census 2010. Adults aged 18 years and above, living in the selected living quarters were approached to participate in the study and requested to complete a set of questionnaires.

Results

A total of 1,556 out of 2,152 participants participated in this study, giving an overall study response rate of 61.90%. Patient Health Questionnaire 9 (PHQ-9) was used to determine the presence of depression. The prevalence of depression was 10.3%, based on the PHQ-9 cut off point of 10 and above. Based on multiple logistic regression analysis, the predictors of depression were presence of anxiety, serious problems at work, unhappy relationship with children, high perceived stress, domestic violence, unhappy relationship with spouse, low self-esteem, unhappy relationship with family, serious financial constraint and presence of chronic diseases. When reanalyzed after removing anxiety, high perceived stress and low self-esteem, additional predictors of depression were found to be serious marital problems and religiosity.

Conclusion

The prevalence of depression in this study is similar to that found in other studies. Findings from this study are being used as baseline data to develop an effective program to assist in the management of common mental health disorders in the community, in particular depression. The identification of predictors of depression in the community is important to identify the target population for the program.     

Rainforest conversion to smallholder cash crops leads to varying declines of beetles (Coleoptera) on Sumatra

Southeast Asian arthropod biodiversity is in rapid decline, but the variability of responses within taxa has received little attention. Using canopy fogging, we collected ~50,000 beetles (Coleoptera) in (1) lowland rainforest, (2) jungle rubber (rubber agroforest), and smallholder monoculture plantations of (3) rubber and (4) oil palm in Sumatra, across two landscapes and seasons. On average, beetle abundance was more than 50%, and biomass over 75%, lower in rubber and oil palm plantations than in rainforest and jungle rubber. This pattern was influenced by landscape and season. Abundance and biomass declines were similar in Chrysomelidae, Elateridae, and Staphylinidae, but differed in Curculionidae, which were most abundant in oil palm due to the introduced oil palm pollinator Elaeidobius kamerunicus. Across beetle families, species richness in monocultures was reduced by at least 70% compared to rainforest, with beetle richness in jungle rubber being similar to rainforest. Community composition in oil palm plantations differed markedly from the other land-use systems for Chrysomelidae and Curculionidae, but less for Elateridae and Staphylinidae. Turnover contributed more to overall beta diversity than nestedness for all families and land-use systems. Likely undersampling of the beetle community in rainforest suggests that declines of beetle density and diversity are much more severe than reported here, especially for beetle families with many concealed species, such as Staphylinidae. This study provides first evidence that negative responses of beetles to tropical land-use change vary among families, and is the first report of its kind from heavily understudied Sumatra.     

De Novo Transcriptomic and Life-History Responses of Moina Micrura Under Stress Environment Conditions

Marine Biotechnology - Moina micrura represents a promising model species for ecological and ecotoxicological investigations in tropical freshwater ecosystems. Illumina NovaSeq™ 6000...     

Synthesis,antioxidant, and molecular docking of new fluorescent (4-alkoxyphenyl)-nitrothiophene compounds

New fluorescent 4-alkoxyphenyl-nitrothiophene compounds 4a–d bearing diverse alkoxyl tails are described. The synthetic strategy was simply accomplished by alkali-assisted alkylation of 4-(5-nitrothiophen-2-yl)phenol ( 3 ) with propyl, hexyl, nonyl, and/or dodecyl iodide. The molecular structures were determined using infrared (IR), ¹H NMR, and mass spectroscopy. Ultraviolet–visible (UV–vis) absorption and emission spectra of the produced 4-alkoxyphenyl-nitrothiophenes revealed considerable extinction coefficients, which were shown to be controlled by the thiophene bridge in conjugation with the alkoxy donor moiety. It was found that the maximum absorbance wavelength was affected by the alkoxyl group-bonded substituents. The antioxidant efficiency obtained from the 4-alkoxyphenyl-nitrothiophene hybrids was excellent compared with that widely used drugs [butylated hydroxytoluene (BHT) and vitamin C]. Unlike 2-(4-[dodecyloxy]phenyl)-5-nitrothiophene hybrid 4d , which has made solid claims about the good effect of its reference drugs and vitamins, Docking investigations of the prepared 4-alkoxyphenyl-nitrothiophene hybrids towards the selected 5IKQ protein revealed impressive coordination and antioxidant effectiveness.