Natural variation in autumn expression is the major adaptive determinant distinguishing Arabidopsis FLC haplotypes.

In Arabidopsis thaliana, winter is registered during vernalization through the temperature-dependent repression and epigenetic silencing of floral repressor FLOWERING LOCUS C (FLC). Natural Arabidopsis accessions show considerable variation in vernalization. However, which aspect of the FLC repression mechanism is most important for adaptation to different environments is unclear. By analysing FLC dynamics in natural variants and mutants throughout winter in three field sites, we find that autumnal FLC expression, rather than epigenetic silencing, is the major variable conferred by the distinct Arabidopsis FLChaplotypes. This variation influences flowering responses of Arabidopsis accessions resulting in an interplay between promotion and delay of flowering in different climates to balance survival and, through a post-vernalization effect, reproductive output. These data reveal how expression variation through non-coding cis variation at FLC has enabled Arabidopsis accessions to adapt to different climatic conditions and year-on-year fluctuations.

ABC transporter genes ABC-C6 and ABC-G33 alter plant-microbe-parasite interactions in the rhizosphere.

Plants are master regulators of rhizosphere ecology, secreting a complex mixture of compounds into the soil, collectively termed plant root exudate. Root exudate composition is highly dynamic and functional, mediating economically important interactions between plants and a wide range of soil organisms. Currently we know very little about the molecular basis of root exudate composition, which is a key hurdle to functional exploitation of root exudates for crop improvement. Root expressed transporters modulate exudate composition and could be manipulated to develop beneficial plant root exudate traits. Using Virus Induced Gene silencing (VIGS), we demonstrate that knockdown of two root-expressed ABC transporter genes in tomato cv. Moneymaker, ABC-C6 and ABC-G33, alters the composition of semi-volatile compounds in collected root exudates. Root exudate chemotaxis assays demonstrate that knockdown of each transporter gene triggers the repulsion of economically relevant Meloidogyne and Globodera spp. plant parasitic nematodes, which are attracted to control treatment root exudates. Knockdown of ABC-C6 inhibits egg hatching of Meloidogyne and Globodera spp., relative to controls. Knockdown of ABC-G33 has no impact on egg hatching of Meloidogyne spp. but has a substantial inhibitory impact on egg hatching of G. pallida. ABC-C6 knockdown has no impact on the attraction of the plant pathogen Agrobacterium tumefaciens, or the plant growth promoting Bacillus subtilis, relative to controls. Silencing ABC-G33 induces a statistically significant reduction in attraction of B. subtilis, with no impact on attraction of A. tumefaciens. By inoculating selected differentially exuded compounds into control root exudates, we demonstrate that hexadecaonic acid and pentadecane are biologically relevant parasite repellents. ABC-C6 represents a promising target for breeding or biotechnology intervention strategies as gene knockdown leads to the repulsion of economically important plant parasites and retains attraction of the beneficial rhizobacterium B. subtilis. This study exposes the link between ABC transporters, root exudate composition, and ex planta interactions with agriculturally and economically relevant rhizosphere organisms, paving the way for new approaches to rhizosphere engineering and crop protection.

Transcriptional variation and divergence of host-finding behaviour in Steinernema carpocapsae infective juveniles.

BACKGROUND: Steinernema carpocapsae is an entomopathogenic nematode that employs nictation and jumping behaviours to find potential insect hosts. Here we aimed to investigate the transcriptional basis of variant host-finding behaviours in the infective juvenile (IJ) stage of three S. carpocapsae strains (ALL, Breton and UK1), with a focus on neuronal genes known to influence behaviour in other nematode species. Identifying gene expression changes that correlate with variant host-finding behaviours will further our understanding of nematode biology. RESULTS: RNA-seq analysis revealed that whilst up to 28% of the S. carpocapsae transcriptome was differentially expressed (P < 0.0001) between strains, remarkably few of the most highly differentially expressed genes (> 2 log2 fold change, P < 0.0001) were from neuronal gene families. S. carpocapsae Breton displays increased chemotaxis toward the laboratory host Galleria mellonella, relative to the other strains. This correlates with the up-regulation of four srsx chemosensory GPCR genes, and a sodium transporter gene, asic-2, relative to both ALL and UK1 strains. The UK1 strain exhibits a decreased nictation phenotype relative to ALL and Breton strains, which correlates with co-ordinate up-regulation of neuropeptide like protein 36 (nlp-36), and down-regulation of an srt family GPCR gene, and a distinct asic-2-like sodium channel paralogue. To further investigate the link between transcriptional regulation and behavioural variation, we sequenced microRNAs across IJs of each strain. We have identified 283 high confidence microRNA genes, yielding 321 predicted mature microRNAs in S. carpocapsae, and find that up to 36% of microRNAs are differentially expressed (P < 0.0001) between strains. Many of the most highly differentially expressed microRNAs (> 2 log2 fold, P < 0.0001) are predicted to regulate a variety of neuronal genes that may contribute to variant host-finding behaviours. We have also found evidence for differential gene isoform usage between strains, which alters predicted microRNA interactions, and could contribute to the diversification of behaviour. CONCLUSIONS: These data provide insight to the transcriptional basis of behavioural variation in S. carpocapsae, supporting efforts to understand the molecular basis of complex behaviours in nematodes.

Ethylene Response Factor (ERF) genes modulate plant root exudate composition and the attraction of plant parasitic nematodes.

Plant root exudates are compositionally diverse, plastic and adaptive. Ethylene signalling influences the attraction of plant parasitic nematodes, presumably through the modulation of root exudate composition. Understanding this pathway could lead to new sources of crop parasite resistance. Here we used Virus-Induced Gene Silencing to knock down the expression of two Ethylene Response Factor (ERF) genes, ERF-E2 and ERF-E3, in tomato. Root exudates were significantly more attractive to the PPNs Meloidogyne incognita and Globodera pallida following knockdown of ERF-E2, which had no impact on the attraction of Meloidogyne javanica. Knockdown of ERF-E3 had no impact on the attraction of Meloidogyne or Globodera spp. Gas Chromatography Mass Spectrometry analysis revealed major changes in root exudate composition relative to controls. However, these changes did not alter the attraction of rhizosphere microbes Bacillus subtilis or Agrobacterium tumefaciens. This study further supports the potential of engineering plant root exudate for parasite control, through the modulation of plant genes.

Transcriptional signatures of invasiveness in Meloidogyne incognita populations from sub-Saharan Africa.

Meloidogyne incognita is an economically important plant parasitic nematode. Here we demonstrate substantial variation in the invasiveness of four M. incognita populations relative to tomato. Infective (J2) stage transcriptomes reveal significant variation in the expression of protein-coding and non-coding RNAs between populations. We identify 33 gene expression markers that correlate with invasiveness, and which map to genes with predicted roles in host finding and invasion, including neuropeptides, ion channels, G Protein-Coupled Receptors, cell wall-degrading enzymes and microRNAs. These data demonstrate a surprising diversity in microRNA complements between populations, and identify gene expression markers for invasiveness of M. incognita, to our knowledge for the first time.

Absence of warmth permits epigenetic memory of winter in Arabidopsis.

Plants integrate widely fluctuating temperatures to monitor seasonal progression. Here, we investigate the temperature signals in field conditions that result in vernalisation, the mechanism by which flowering is aligned with spring. We find that multiple, distinct aspects of the temperature profile contribute to vernalisation. In autumn, transient cold temperatures promote transcriptional shutdown of Arabidopsis FLOWERING LOCUS C (FLC), independently of factors conferring epigenetic memory. As winter continues, expression of VERNALIZATION INSENSITIVE3 (VIN3), a factor needed for epigenetic silencing, is upregulated by at least two independent thermosensory processes. One integrates long-term cold temperatures, while the other requires the absence of daily temperatures above 15 °C. The lack of spikes of high temperature, not just prolonged cold, is thus the major driver for vernalisation. Monitoring of peak daily temperature is an effective mechanism to judge seasonal progression, but is likely to have deleterious consequences for vernalisation as the climate becomes more variable.

A neuropeptide modulates sensory perception in the entomopathogenic nematode Steinernema carpocapsae.

Entomopathogenic nematodes (EPNs) employ a sophisticated chemosensory apparatus to detect potential hosts. Understanding the molecular basis of relevant host-finding behaviours could facilitate improved EPN biocontrol approaches, and could lend insight to similar behaviours in economically important mammalian parasites. FMRFamide-like peptides are enriched and conserved across the Phylum Nematoda, and have been linked with motor and sensory function, including dispersal and aggregating behaviours in the free living nematode Caenorhabditis elegans. The RNA interference (RNAi) pathway of Steinernema carpocapsae was characterised in silico, and employed to knockdown the expression of the FMRFamide-like peptide 21 (GLGPRPLRFamide) gene (flp-21) in S. carpocapsae infective juveniles; a first instance of RNAi in this genus, and a first in an infective juvenile of any EPN species. Our data show that 5 mg/ml dsRNA and 50 mM serotonin triggers statistically significant flp-21 knockdown (-84%***) over a 48 h timecourse, which inhibits host-finding (chemosensory), dispersal, hyperactive nictation and jumping behaviours. However, whilst 1 mg/ml dsRNA and 50 mM serotonin also triggers statistically significant flp-21 knockdown (-51%**) over a 48 h timecourse, it does not trigger the null sensory phenotypes; statistically significant target knockdown can still lead to false negative results, necessitating appropriate experimental design. SPME GC-MS volatile profiles of two EPN hosts, Galleria mellonella and Tenebrio molitor reveal an array of shared and unique compounds; these differences had no impact on null flp-21 RNAi phenotypes for the behaviours assayed. Localisation of flp-21 / FLP-21 to paired anterior neurons by whole mount in situ hybridisation and immunocytochemistry corroborates the RNAi data, further suggesting a role in sensory modulation. These data can underpin efforts to study these behaviours in other economically important parasites, and could facilitate molecular approaches to EPN strain improvement for biocontrol.

Ravishing or ravaged: women's relationships with women in the context of aging and Western beauty culture.

We undertook this narrative analysis study to explore the complexities of women's relationships with other women within the sociocultural milieu of beautyism and ageism. Using an open-ended narrative framework, four focus groups of women living in different regions throughout the U.S. were conducted and analyzed to identify thematic categories within and across group sessions. We discuss four of the six key themes discovered in response to the primary research question: How does beauty culture shape women's experiences of aging and their relationships with women of all ages? We conclude that Western idealized beauty standards exert a divisive impact on women's relationships with each other across the life span, negatively affecting their socioemotional well-being, especially in old age.

What's the use in getting mad? Anger and instrumentality in women's relationships.

In two studies, we examined women's anger expression and its instrumental function in relationships by addressing the following questions: What is the relationship between women's self-reports of instrumentality and their perceived styles of anger expression? In what ways and situations do women see their anger expression as instrumental or goal enhancing? In Study I, we expected that women's perceived styles of anger expression would be positively related to instrumentality, as measured with the Personal Attributes Questionnaire (PAQ; Spence, Helmreich, & Stapp, JSAS Catalog of Selected Documents in Psychology, 4, 43, 1974). Although our hypothesis was not supported, a positive relationship did emerge between assertiveness and instrumentality, as predicted. In Study II, we conducted three focus group discussions to elucidate women's experiences of anger and to provide clarification for the results of Study I. We identified group themes related to when women experienced their anger expression as instrumental as well as when women perceived themselves as noninstrumental in anger-arousing situations. In their narratives, women explained how they make decisions about expressing their anger based on relationship concerns.

Who me, angry? Patterns of anger diversion in women.

Researchers suggest that women's experience of anger is very complex and may not be accounted for by existing anger models. The current study was an attempt to clarify a model of women's anger proposed by Cox, Stabb, and Bruckner in Women's Anger: Clinical and Developmental Perspectives, 1999. Anger diversion focuses on women's attempts to bypass anger awareness, to use indirect means to cope with anger, or both. A sample of predominantly college and graduate student women (N = 514) completed a vignette questionnaire assessing diversionary anger styles as well as instruments evaluating symptoms, anger behaviors, emotional expression, and tendencies to respond in socially desirable ways. The results of the study partially support Cox and colleagues' model, particularly in distinguishing between diverting anger and expressing anger assertively. We found that women who divert anger are more vulnerable to symptoms such as depression, anxiety, and somatization than are women who use an assertive approach to coping with anger.

Not your parent's wheelchair.

A pediatric wheelchair is indeed a smaller seating system mounted over a mobility base that helps a child get from point A to point B. The important thing to recognize is that the child is every day learning new things about how he or she fits in with the world. That child is making friends and exploring the playground and going to music or art class. He or she may be starting and ending the day with a parent, but midday is spent interacting with the school's bus driver, teachers, counselor, and therapists. It is the responsibility of the rehab specialist to make sure that, while using a wheelchair to get from point A to point B in all of these different settings and with all of these different people, that disability does not slow the child down.

Critical care of the morbidly obese.

This article describes the special needs of the critically ill morbidly obese, with a focus on the care of the postoperative obesity surgery patient. The technique of surgery is described elsewhere in this journal. Details of nursing care complicated by obesity are discussed. Environment of care modifications required for routine care of the morbidly obese in critical care are detailed. Pharmacokinetic factors to be considered are reviewed. A case study is presented to coalesce concepts presented.