MicroRNA Transcriptomic Analysis of Heterosis during Maize Seed Germination

Heterosis has been utilized widely in the breeding of maize and other crops, and plays an important role in increasing yield, improving quality and enhancing stresses resistance, but the molecular mechanism responsible for heterosis is far from clear. To illustrate whether miRNA-dependent gene regulation is responsible for heterosis during maize germination, a deep-sequencing technique was applied to germinating embryos of a maize hybrid, Yuyu22, which is cultivated widely in China and its parental inbred lines, Yu87-1 and Zong3. The target genes of several miRNAs showing significant expression in the hybrid and parental lines were predicted and tested using real-time PCR. A total of 107 conserved maize miRNAs were co-detected in the hybrid and parental lines. Most of these miRNAs were expressed non-additively in the hybrid compared to its parental lines. These results indicated that miRNAs might participate in heterosis during maize germination and exert an influence via the decay of their target genes. Novel miRNAs were predicted follow a rigorous criterion and only the miRNAs detected in all three samples were treated as a novel maize miRNA. In total, 34 miRNAs belonged to 20 miRNA families were predicted in germinating maize seeds. Global repression of miRNAs in the hybrid, which might result in enhanced gene expression, might be one reason why the hybrid showed higher embryo germination vigor compared to its parental lines

Identification and Characterization of NF-Y Transcription Factor Families in the Monocot Model Plant Brachypodium distachyon

BACKGROUND: Nuclear Factor Y (NF-Y) is a heterotrimeric transcription factor composed of NF-YA, NF-YB and NF-YC proteins. Using the dicot plant model system Arabidopsis thaliana (Arabidopsis), NF-Y were previously shown to control a variety of agronomically important traits, including drought tolerance, flowering time, and seed development. The aim of the current research was to identify and characterize NF-Y families in the emerging monocot model plant Brachypodium distachyon (Brachypodium) with the long term goal of assisting in the translation of known dicot NF-Y functions to the grasses. METHODOLOGY/PRINCIPAL FINDINGS: We identified, annotated, and further characterized 7 NF-YA, 17 NF-YB, and 12 NF-YC proteins in Brachypodium (BdNF-Y). By examining phylogenetic relationships, orthology predictions, and tissue-specific expression patterns for all 36 BdNF-Y, we proposed numerous examples of likely functional conservation between dicots and monocots. To test one of these orthology predictions, we demonstrated that a BdNF-YB with predicted orthology to Arabidopsis floral-promoting NF-Y proteins can rescue a late flowering Arabidopsis mutant. CONCLUSIONS/SIGNIFICANCE: The Brachypodium genome encodes a similar complement of NF-Y to other sequenced angiosperms. Information regarding NF-Y phylogenetic relationships, predicted orthologies, and expression patterns can facilitate their study in the grasses. The current data serves as an entry point for translating many NF-Y functions from dicots to the genetically tractable monocot model system Brachypodium. In turn, studies of NF-Y function in Brachypodium promise to be more readily translatable to the agriculturally important grasses

Cryptococcus: from environmental saprophyte to global pathogen.

Cryptococcosis is a globally distributed invasive fungal infection that is caused by species within the genus Cryptococcus which presents substantial therapeutic challenges. Although natural human-to-human transmission has never been observed, recent work has identified multiple virulence mechanisms that enable cryptococci to infect, disseminate within and ultimately kill their human host. In this Review, we describe these recent discoveries that illustrate the intricacy of host-pathogen interactions and reveal new details about the host immune responses that either help to protect against disease or increase host susceptibility. In addition, we discuss how this improved understanding of both the host and the pathogen informs potential new avenues for therapeutic development

Dental Treatment in a State-Funded Primary Dental Care Facility: Contextual and Individual Predictors of Treatment Need?

OBJECTIVE:This study examined individual and contextual factors which predict the dental care received by patients in a state-funded primary dental care training facility in England. METHODS:Routine clinical and demographic data were extracted from a live dental patient management system in a state-funded facility using novel methods. The data, spanning a four-year period [2008-2012] were cleaned, validated, linked by means of postcode to deprivation status, and analysed to identify factors which predict dental treatment need. The predictive relationship between patients' individual characteristics (demography, smoking, payment status) and contextual experience (deprivation based on area of residence), with common dental treatments received was examined using unadjusted analysis and adjusted logistic regression. Additionally, multilevel modelling was used to establish the isolated influence of area of residence on treatments. RESULTS:Data on 6,351 dental patients extracted comprised of 147,417 treatment procedures delivered across 10,371 courses of care. Individual level factors associated with the treatments were age, sex, payment exemption and smoking status and deprivation associated with area of residence was a contextual predictor of treatment. More than 50% of children (<18 years) and older adults (≥65 years) received preventive care in the form of 'instruction and advice', compared with 46% of working age adults (18-64 years); p = 0.001. The odds of receiving treatment increased with each increasing year of age amongst adults (p = 0.001): 'partial dentures' (7%); 'scale and polish' (3.7%); 'tooth extraction' (3%; p = 0.001), and 'instruction and advice' (3%; p = 0.001). Smokers had a higher likelihood of receiving all treatments; and were notably over four times more likely to receive 'instruction and advice' than non-smokers (OR 4.124; 95% CI: 3.088-5.508; p = 0.01). A further new finding from the multilevel models was a significant difference in treatment related to area of residence; adults from the most deprived quintile were more likely to receive 'tooth extraction' when compared with least deprived, and less likely to receive preventive 'instruction and advice' (p = 0.01). CONCLUSION:This is the first study to model patient management data from a state-funded dental service and show that individual and contextual factors predict common treatments received. Implications of this research include the importance of making provision for our aging population and ensuring that preventative care is available to all. Further research is required to explain the interaction of organisational and system policies, practitioner and patient perspectives on care and, thus, inform effective commissioning and provision of dental services

NUCLEAR FACTOR Y, Subunit C (NF-YC) Transcription Factors Are Positive Regulators of Photomorphogenesis in Arabidopsis thaliana

We thank Dr. Ben Smith (University of Oklahoma) for assistance with FLIM-FRET measurements and Dr. Min Ni (University of Minnesota) for critical reading of the manuscript. The cop1-4 mutant allele and cop1-4 co-9 cross were kindly provided by George Coupland (Max Planck Institute).Author Summary Light perception is critically important for the fitness of plants in both natural and agricultural settings. Plants not only use light for photosynthesis, but also as a cue for proper development. As a seedling emerges from soil it must determine the light environment and adopt an appropriate growth habit. When blue and red wavelengths are the dominant sources of light, plants will undergo photomorphogenesis. Photomorphogenesis describes a number of developmental responses initiated by light in a seedling, and includes shortened stems and establishing the ability to photosynthesize. The genes regulating photomorphogenesis have been studied extensively, but a complete picture remains elusive. Here we describe the finding that NUCLEAR FACTOR-Y (NF-Y) genes are positive regulators of photomorphogenesis—i.e., in plants where NF-Y genes are mutated, they display some characteristics of dark grown plants, even though they are in the light. Our data suggests that the roles of NF-Y genes in light perception do not fit in easily with those of other described pathways. Thus, studying these genes promises to help develop a more complete picture of how light drives plant development.Yeshttp://www.plosgenetics.org/static/editorial#pee