32 research outputs found
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The Enigmatic Canal-Associated Neurons Regulate Caenorhabditis elegans Larval Development Through a cAMP Signaling Pathway.
Caenorhabditis elegans larval development requires the function of the two Canal-Associated Neurons (CANs): killing the CANs by laser microsurgery or disrupting their development by mutating the gene ceh-10 results in early larval arrest. How these cells promote larval development, however, remains a mystery. In screens for mutations that bypass CAN function, we identified the gene kin-29, which encodes a member of the Salt-Inducible Kinase (SIK) family and a component of a conserved pathway that regulates various C. elegans phenotypes. Like kin-29 loss, gain-of-function mutations in genes that may act upstream of kin-29 or growth in cyclic-AMP analogs bypassed ceh-10 larval arrest, suggesting that a conserved adenylyl cyclase/PKA pathway inhibits KIN-29 to promote larval development, and that loss of CAN function results in dysregulation of KIN-29 and larval arrest. The adenylyl cyclase ACY-2 mediates CAN-dependent larval development: acy-2 mutant larvae arrested development with a similar phenotype to ceh-10 mutants, and the arrest phenotype was suppressed by mutations in kin-29 ACY-2 is expressed predominantly in the CANs, and we provide evidence that the acy-2 functions in the CANs to promote larval development. By contrast, cell-specific expression experiments suggest that kin-29 acts in both the hypodermis and neurons, but not in the CANs. Based on our findings, we propose two models for how ACY-2 activity in the CANs regulates KIN-29 in target cells
Genome-wide association study identifies the SERPINB gene cluster as a susceptibility locus for food allergy
Genetic factors and mechanisms underlying food allergy are largely unknown.
Due to heterogeneity of symptoms a reliable diagnosis is often difficult to
make. Here, we report a genome-wide association study on food allergy
diagnosed by oral food challenge in 497 cases and 2387 controls. We identify
five loci at genome-wide significance, the clade B serpin (SERPINB) gene
cluster at 18q21.3, the cytokine gene cluster at 5q31.1, the filaggrin gene,
the C11orf30/LRRC32 locus, and the human leukocyte antigen (HLA) region.
Stratifying the results for the causative food demonstrates that association
of the HLA locus is peanut allergy-specific whereas the other four loci
increase the risk for any food allergy. Variants in the SERPINB gene cluster
are associated with SERPINB10 expression in leukocytes. Moreover, SERPINB
genes are highly expressed in the esophagus. All identified loci are involved
in immunological regulation or epithelial barrier function, emphasizing the
role of both mechanisms in food allergy
Prospective study of the primary evaluation of 1016 horses with clinical signs of abdominal pain by veterinary practitioners, and the differentiation of critical and nonâcritical cases
Background: The majority of research on the evaluation of horses with colic is focused on referral hospital populations. Early identification of critical cases is important to optimise outcome and welfare. The aim of this prospective study was to survey the primary evaluation of horses with clinical signs of abdominal pain by veterinary practitioners, and compare the initial presentation of critical and non-critical cases.
Results: Data from 1016 primary evaluations of horses presenting with clinical signs of colic were submitted by 167 veterinary practitioners across the United Kingdom over a 13 month period. The mean age of the study population was 13.5 years (median 12.0, range 0â42). Mean heart rate on primary presentation was 47 beats/min (median 44, range 18â125), mean respiratory rate was 20 breaths/min (median 16, range 6â100), and median gastrointestinal auscultation score (0â12, minimumâmaximum) was 5 (range 0â12). Clinical signs assessed using a behavioural severity score (0â17, minimumâmaximum), were between 0 and 6 in 70.4 % of cases, and 7 12 for 29.6 % of cases. Rectal examination was performed in 73.8 % of cases. Cases that responded positively to simple medical treatment were categorised retrospectively as ânon-criticalâ; cases that required intensive medical treatment, surgical intervention, died or were euthanased were categorised as âcriticalâ. Eight-hundred-and-twenty- two cases met these criteria; 76.4 % were ânon-criticalâ and 23.6 % were âcriticalâ. Multivariable logistic regression was used to identify features of the clinical presentation associated with critical cases. Five variables were retained in the final multivariable model: combined pain score: (OR 1.19, P 2.5 s (OR 3.21, P = 0.046, 95 % CI 1.023â10.09), weak pulse character (OR 2.90, P = 0.004, 95 % CI 1.39â5.99) and absence of gut sounds in â„1 quadrant (OR 3.65, P < 0.001, 95 % CI 2.08â6.41).
Conclusions: This is the first study comparing the primary presentation of critical and non-critical cases of abdominal pain. Pain, heart rate, gastrointestinal borborygmi and simple indicators of hypovolaemia were significant indicators of critical cases, even at the primary veterinary examination, and should be considered essential components of the initial assessment and triage of horses presenting with colic
Shared genetic origin of asthma, hay fever and eczema elucidates allergic disease biology
Asthma, hay fever (or allergic rhinitis) and eczema (or atopic dermatitis) often coexist in the same individuals, partly because of a shared genetic origin. To identify shared risk variants, we performed a genome-wide association study (GWAS; n = 360,838) of a broad allergic disease phenotype that considers the presence of any one of these three diseases. We identified 136 independent risk variants (P < 3 Ă 10-8), including 73 not previously reported, which implicate 132 nearby genes in allergic disease pathophysiology. Disease-specific effects were detected for only six variants, confirming that most represent shared risk factors. Tissue-specific heritability and biological process enrichment analyses suggest that shared risk variants influence lymphocyte-mediated immunity. Six target genes provide an opportunity for drug repositioning, while for 36 genes CpG methylation was found to influence transcription independently of genetic effects. Asthma, hay fever and eczema partly coexist because they share many genetic risk variants that dysregulate the expression of immune-related genes
Rare variant analysis in eczema identifies exonic variants in DUSP1, NOTCH4 and SLC9A4
Previous genome-wide association studies revealed multiple common variants involved in eczema but the role of rare variants remains to be elucidated. Here, we investigate the role of rare variants in eczema susceptibility. We meta-analyze 21 study populations including 20,016 eczema cases and 380,433 controls. Rare variants are imputed with high accuracy using large population-based reference panels. We identify rare exonic variants in DUSP1, NOTCH4, and SLC9A4 to be associated with eczema. In DUSP1 and NOTCH4 missense variants are predicted to impact conserved functional domains. In addition, five novel common variants at SATB1-AS1/KCNH8, TRIB1/LINC00861, ZBTB1, TBX21/OSBPL7, and CSF2RB are discovered. While genes prioritized based on rare variants are significantly up-regulated in the skin, common variants point to immune cell function. Over 20% of the single nucleotide variant-based heritability is attributable to rare and low-frequency variants. The identified rare/low-frequency variants located in functional protein domains point to promising targets for novel therapeutic approaches to eczema