E-cadherin-mediated cell-cell adhesion and signaling plays an essential role in development and maintenance of healthy epithelial tissues. Adhesiveness mediated by E-cadherin is conferred by its ...extracellular cadherin domains and is regulated by an assembly of intracellular adaptors and enzymes associated with its cytoplasmic tail. We used proximity biotinylation and quantitative proteomics to identify 561 proteins in the vicinity of the cytoplasmic tail of E-cadherin. In addition, we used proteomics to identify proteins associated with E-cadherin-containing adhesion plaques from a cell-glass interface, which enabled the assignment of cellular localization to putative E-cadherin-interacting proteins. Moreover, by tagging identified proteins with GFP (green fluorescent protein), we determined the subcellular localization of 83 putative E-cadherin-proximal proteins and identified 24 proteins that were previously uncharacterized as part of adherens junctions. We constructed and characterized a comprehensive E-cadherin interaction network of 79 published and 394 previously uncharacterized proteins using a structure-informed database of protein-protein interactions. Finally, we found that calcium chelation, which disrupts the interaction of the extracellular E-cadherin domains, did not disrupt most intracellular protein interactions with E-cadherin, suggesting that the E-cadherin intracellular interactome is predominantly independent of cell-cell adhesion.
Summary
Cyanogenic glucosides are nitrogen‐containing specialized metabolites that provide chemical defense against herbivores and pathogens via the release of toxic hydrogen cyanide. It has been ...suggested that cyanogenic glucosides are also a store of nitrogen that can be remobilized for general metabolism via a previously unknown pathway. Here we reveal a recycling pathway for the cyanogenic glucoside dhurrin in sorghum (Sorghum bicolor) that avoids hydrogen cyanide formation. As demonstrated in vitro, the pathway proceeds via spontaneous formation of a dhurrin‐derived glutathione conjugate, which undergoes reductive cleavage by glutathione transferases of the plant‐specific lambda class (GSTLs) to produce p‐hydroxyphenyl acetonitrile. This is further metabolized to p‐hydroxyphenylacetic acid and free ammonia by nitrilases, and then glucosylated to form p‐glucosyloxyphenylacetic acid. Two of the four GSTLs in sorghum exhibited high stereospecific catalytic activity towards the glutathione conjugate, and form a subclade in a phylogenetic tree of GSTLs in higher plants. The expression of the corresponding two GSTLs co‐localized with expression of the genes encoding the p‐hydroxyphenyl acetonitrile‐metabolizing nitrilases at the cellular level. The elucidation of this pathway places GSTs as key players in a remarkable scheme for metabolic plasticity allowing plants to reverse the resource flow between general and specialized metabolism in actively growing tissue.
Significance Statement
Glutathione transferase enzymes (GSTs) are highly abundant in plants, but only very few have been assigned a physiological function. Here we demonstrate that GSTs are key players in a pathway for endogenous recycling of a cyanogenic glucoside defense compound in sorghum, revealing that plants continuously optimize, and can even reverse, their allocation of resources between general and specialized metabolism.
Hypoxaemia during labour can alter the shape of the fetal electrocardiogram (ECG) waveform, notably the relation of the PR to RR intervals, and elevation or depression of the ST segment. Technical ...systems have therefore been developed to monitor the fetal ECG during labour as an adjunct to continuous electronic fetal heart rate monitoring with the aim of improving fetal outcome and minimising unnecessary obstetric interference.
To compare the effects of analysis of fetal ECG waveforms during labour with alternative methods of fetal monitoring.
We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (April 2006).
Randomised trials comparing fetal ECG waveform analysis with alternative methods of fetal monitoring during labour.
Trial quality assessment and data extraction were performed by the review author, without blinding.
Four trials including a total of 9829 women were included. In comparison to continuous electronic fetal heart rate monitoring alone, the use of adjunctive ST waveform analysis (three trials, 8872 women) was associated with fewer babies with severe metabolic acidosis at birth (cord pH less than 7.05 and base deficit greater than 12 mmol/L) (relative risk (RR) 0.64, 95% confidence interval (CI) 0.41 to 1.00, data from 8108 babies), fewer babies with neonatal encephalopathy (three trials, RR 0.33, 95% CI 0.11 to 0.95) although the absolute number of babies with encephalopathy was low (n = 17), fewer fetal scalp samples during labour (three trials, RR 0.76, 95% CI 0.67 to 0.86) and fewer operative vaginal deliveries (three trials, RR 0.87, 95% CI 0.78 to 0.96). There was no statistically significant difference in caesarean section (three trials, RR 0.97, 95% CI 0.84 to 1.11), Apgar score less than seven at five minutes (three trials, RR 0.80, 95% CI 0.56 to 1.14), or admissions to special care unit (three trials, RR 0.90, 95% CI 0.75 to 1.08). Apart from a trend towards fewer operative deliveries (one trial, RR 0.87, 95% CI 0.76 to 1.01), there was little evidence that monitoring by PR interval analysis conveyed any benefit.
These findings provide some support for the use of fetal ST waveform analysis when a decision has been made to undertake continuous electronic fetal heart rate monitoring during labour. However, the advantages need to be considered along with the disadvantages of needing to use an internal scalp electrode, after membrane rupture, for ECG waveform recordings.
Treatment with heat-stable carbetocin after vaginal delivery was noninferior to oxytocin for prevention of blood loss of at least 500 ml or use of uterotonics. Noninferiority was not shown for ...prevention of blood loss of at least 1000 ml, but event rates were low.
Objective
To apply the World Health Organization (WHO) Application of the International Classification of Diseases, tenth revision (ICD‐10) to deaths during the perinatal period: ICD‐Perinatal ...Mortality (ICD‐PM) to existing perinatal death databases.
Design
Retrospective application of ICD‐PM.
Setting
South Africa, UK.
Population
Perinatal death databases.
Methods
Deaths were grouped according to timing of death and then by the ICD‐PM cause of death. The main maternal condition at the time of perinatal death was assigned to each case.
Main outcome measures
Causes of perinatal mortality, associated maternal conditions.
Results
In South Africa 344/689 (50%) deaths occurred antepartum, 11% (n = 74) intrapartum and 39% (n = 271) in the early neonatal period. In the UK 4377/9067 (48.3%) deaths occurred antepartum, with 457 (5%) intrapartum and 4233 (46.7%) in the neonatal period. Antepartum deaths were due to unspecified causes (59%), chromosomal abnormalities (21%) or problems related to fetal growth (14%). Intrapartum deaths followed acute intrapartum events (69%); neonatal deaths followed consequences of low birthweight/ prematurity (31%), chromosomal abnormalities (26%), or unspecified causes in healthy mothers (25%). Mothers were often healthy; 53%, 38% and 45% in the antepartum, intrapartum and neonatal death groups, respectively. Where there was a maternal condition, it was most often maternal medical conditions, and complications of placenta, cord and membranes.
Conclusions
The ICD‐PM can be a globally applicable perinatal death classification system that emphasises the need for a focus on the mother—baby dyad as we move beyond 2015.
Tweetable
ICD‐PM is a global system that classifies perinatal deaths and links them to maternal conditions.
Tweetable
ICD‐PM is a global system that classifies perinatal deaths and links them to maternal conditions.
The emergence of complex electronic behaviour from simple ingredients has resulted in the discovery of numerous states of matter. Many examples are found in systems exhibiting geometric magnetic ...frustration, which prevents simultaneous satisfaction of all magnetic interactions. This frustration gives rise to complex magnetic properties such as chiral spin structures, orbitally driven magnetism, spin-ice behaviour exhibiting Dirac strings with magnetic monopoles, valence-bond solids and spin liquids. Here we report the synthesis and characterization of LiZn(2)Mo(3)O(8), a geometrically frustrated antiferromagnet in which the magnetic moments are localized on small transition-metal clusters rather than individual ions. By doing so, first-order Jahn-Teller instabilities and orbital ordering are prevented, allowing the strongly interacting magnetic clusters in LiZn(2)Mo(3)O(8) to probably give rise to an exotic condensed valence-bond ground state reminiscent of the proposed resonating valence-bond state. Our results also link magnetism on clusters to geometric magnetic frustration in extended solids, demonstrating a new approach for unparalleled chemical control and tunability in the search for collective, emergent electronic states of matter.
Trpm8 (transient receptor potential cation channel, subfamily M, member 8) is expressed by sensory neurons and is involved in the detection of environmental cold temperatures. TRPM8 activity triggers ...an increase in uncoupling protein 1 (Ucp1)-dependent brown adipose tissue (BAT) thermogenesis. Bone density and marrow adipose tissue are both influenced by rodent housing temperature and brown adipose tissue, but it is unknown if TRPM8 is involved in the co-regulation of thermogenesis and bone homeostasis. To address this, we examined the bone phenotypes of one-year-old Trpm8 knockout mice (Trpm8-KO) after a 4-week cold temperature challenge. Male Trpm8-KO mice had lower bone mineral density than WT, with smaller bone size (femur length and cross-sectional area) being the most striking finding, and exhibited a delayed cold acclimation with increased BAT expression of Dio2 and Cidea compared to WT. In contrast to males, female Trpm8-KO mice had low vertebral bone microarchitectural parameters, but no genotype-specific alterations in body temperature. Interestingly, Trpm8 was not required for cold-induced trabecular bone loss in either sex, but bone marrow adipose tissue in females was significantly suppressed by Trpm8 deletion. In summary, we identified sex differences in the role of TRPM8 in maintaining body temperature, bone microarchitecture and marrow adipose tissue. Identifying mechanisms through which cold temperature and BAT influence bone could help to ameliorate potential bone side effects of obesity treatments designed to stimulate thermogenesis.
The formation of a functional blood vessel network relies on the ability of endothelial cells (ECs) to dynamically rearrange their adhesive contacts in response to blood flow and guidance cues, such ...as vascular endothelial growth factor-A (VEGF-A) and class 3 semaphorins (SEMA3s). Neuropilin 1 (NRP1) is essential for blood vessel development, independently of its ligands VEGF-A and SEMA3, through poorly understood mechanisms. Grounding on unbiased proteomic analysis, we report here that NRP1 acts as an endocytic chaperone primarily for adhesion receptors on the surface of unstimulated ECs. NRP1 localizes at adherens junctions (AJs) where, interacting with VE-cadherin, promotes its basal internalization-dependent turnover and favors vascular permeability initiated by histamine in both cultured ECs and mice. We identify a splice variant of tryptophanyl-tRNA synthetase (mini-WARS) as an unconventionally secreted extracellular inhibitory ligand of NRP1 that, by stabilizing it at the AJs, slows down both VE-cadherin turnover and histamine-elicited endothelial leakage. Thus, our work shows a role for NRP1 as a major regulator of AJs plasticity and reveals how mini-WARS acts as a physiological NRP1 inhibitory ligand in the control of VE-cadherin endocytic turnover and vascular permeability.
PDF
