Orchids are the most diverse family of angiosperms, with over 25 000 species, more than mammals, birds and reptiles combined. Tests of hypotheses to account for such diversity have been stymied by the lack of a fully resolved broad-scale phylogeny. Here, we provide such a phylogeny, based on 75 chloroplast genes for 39 species representing all orchid subfamilies and 16 of 17 tribes, time-calibrated against 17 angiosperm fossils. A supermatrix analysis places an additional 144 species based on three plastid genes. Orchids appear to have arisen roughly 112 million years ago (Mya); the subfamilies Orchidoideae and Epidendroideae diverged from each other at the end of the Cretaceous; and the eight tribes and three previously unplaced subtribes of the upper epidendroids diverged rapidly from each other between 37.9 and 30.8 Mya. Orchids appear to have undergone one significant acceleration of net species diversification in the orchidoids, and two accelerations and one deceleration in the upper epidendroids. Consistent with theory, such accelerations were correlated with the evolution of pollinia, the epiphytic habit, CAM photosynthesis, tropical distribution (especially in extensive cordilleras), and pollination via Lepidoptera or euglossine bees. Deceit pollination appears to have elevated the number of orchid species by one-half but not via acceleration of the rate of net diversification. The highest rate of net species diversification within the orchids (0.382 sp sp 21 My 21) is 6.8 times that at the Asparagales crown.

Adaptor protein-2 (AP2), a central component of clathrin-coated vesicles (CCVs), is pivotal in clathrin-mediated endocytosis which internalises plasma membrane constituents such as G protein-coupled receptors (GPCRs)1-3 . AP2, a heterotetramer of alpha, beta, mu and sigma subunits, links clathrin to vesicle membranes and binds to tyrosine-based and dileucine-based motifs of membrane-associated cargo proteins1,4. Here, we show that AP2 sigma subunit (AP2S1) missense mutations, which all involved the Arg15 residue (Arg15Cys, Arg15His and Arg15Leu) that forms key contacts with dileucine-based motifs of CCV cargo proteins4, result in familial hypocalciuric hypercalcemia type 3 (FHH3), an extracellular-calcium homeostasis disorder affecting parathyroids, kidneys and bone5-7 These AP2S1 mutations occurred in >20% of FHH patients without calcium-sensing GPCR (CaSR) mutations which cause FHH18-12. AP2S1 mutations decreased the sensitivity of CaSR-expressing cells to extracellular-calcium and reduced CaSR endocytosis, likely through a loss of interaction with a C-terminus CaSR dileucine-based motif whose disruption also decreased intracellular signalling. Thus, our results reveal a new role for AP2 in extracellular-calcium homeostasis.

OBJECTIVESpecific autoantibodies characterize type 1 diabetes in childhood but are also found in adult-onset diabetes, even when initially non–insulin requiring, e.g., with latent autoimmune diabetes (LADA). We aimed to characterize adult-onset autoimmune diabetes.RESEARCH DESIGN AND METHODSWe consecutively studied 6,156 European diabetic patients attending clinics within 5 years of diagnosis (age range, 30–70 years) examined cross-sectionally clinically and for GAD antibodies (GADA) and antibodies to insulinoma-associated antigen-2 (IA-2A) and zinc-transporter 8 (ZnT8A).RESULTSOf 6,156 patients, 541 (8.8%) had GADA and only 57 (0.9%) IA-2A or ZnT8A alone. More autoantibody-positive than autoantibody-negative patients were younger, leaner, on insulin (49.5 vs. 13.2%), and female (P < 0.0001 for each), though LADA patients (9.7% of total) did not show categorically distinct clinical features from autoantibody-negative type 2 diabetes. Similarly, more GADA patients with high (>200 World Health Organization IU) (n = 403) compared with low (n = 138) titer were female, lean, and insulin treated (54.6 vs. 39.7%) (P < 0.02 for each). Autoantibody-positive patients usually had GADA (541 of 598; 90.5%) and had LADA more often than type 1 autoimmune diabetes (odds ratio 3.3).CONCLUSIONSAdult-onset autoimmune diabetes emerges as a prevalent form of autoimmune diabetes. Our results indicate that adult-onset autoimmune diabetes in Europe encompasses type 1 diabetes and LADA in the same broad clinical and autoantibody-positive spectrum. At diagnosis, patients with adult-onset autoimmune diabetes are usually non–insulin requiring and clinically indistinguishable from patients with type 2 diabetes, though they tend to be younger and leaner. Only with screening for autoantibodies, especially GADA, can they be identified with certainty.

Aims/hypothesis Glomerular hyperfiltration is a wellestablished phenomenon occurring early in some patients with type 1 diabetes. However, there is no consistent answer regarding whether hyperfiltration predicts later development of nephropathy. We performed a systematic review and meta-analysis of observational studies that compared the risk of developing diabetic nephropathy in patients with and without glomerular hyperfiltration and also explored the impact of baseline GFR. Methods A systematic review and meta-analysis was carried out. Cohort studies in type 1 diabetic participants were included if they contained data on the development of incipient or overt nephropathy with baseline measurement of GFR and presence or absence of hyperfiltration. Results We included ten cohort studies following 780 patients. After a study median follow-up of 11.2 years, 130 patients had developed nephropathy. Using a random effects model, the pooled odds of progression to a minimum of microalbuminuria in patients with hyperfiltration was 2.71 (95% CI 1.20-6.11) times that of patients with normofiltration. There was moderate heterogeneity (heterogeneity test p=0.05, measure of degree of inconsistency= 48%) and some evidence of funnel plot asymmetry, possibly due to publication bias. The pooled weighted mean difference in baseline GFR was 13.8 ml min −1 1.73 m −2 (95% CI 5.0-22.7) greater in the group progressing to nephropathy than in those not progressing (heterogeneity test p<0.01). Conclusions/interpretation In published studies, individuals with glomerular hyperfiltration were at increased risk of progression to diabetic nephropathy using study level data. Further larger studies are required to explore this relationship and the role of potential confounding variables.

AimOrchidaceae is the most species-rich angiosperm family and has one of the broadest distributions. Until now, the lack of a well-resolved phylogeny has prevented analyses of orchid historical biogeography. In this study, we use such a phylogeny to estimate the geographical spread of orchids, evaluate the importance of different regions in their diversification and assess the role of long-distance dispersal (LDD) in generating orchid diversity. LocationGlobal. MethodsAnalyses use a phylogeny including species representing all five orchid subfamilies and almost all tribes and subtribes, calibrated against 17 angiosperm fossils. We estimated historical biogeography and assessed the importance of different regions for rates of speciation, extinction and net species diversification. We evaluated the impact of particular LDD events on orchid diversity by asking how many species evolved in the new range subsequent to those events. ResultsOrchids appear to have arisen in Australia 112Ma (95% higher probability distribution: 102.0-120.0Ma), then spread to the Neotropics via Antarctica by 90Ma (HPD: 79.7-99.5Ma), when all three continents were in close contact and apostasioids split from the ancestor of all other orchids. Ancestors of vanilloids, cypripedioids and orchidoids+epidendroids appear to have originated in the Neotropics 84-64Ma. Repeated long- and short-distance dispersal occurred through orchid history: stochastic mapping identified a mean total of 74 LDD events or 0.8Ma(-1). Across orchid history, Southeast Asia was the most important source and maximally accelerated net diversification; across epidendroids, the Neotropics maximally accelerated diversification. Main conclusionsOur analysis provides the first biogeographical history of the orchids, implicating Australia, the Neotropics and Antarctica in their origin. LDD and life in the Neotropics - especially the Andes - had profound effects on their spread and diversification; >97% of all orchid species are restricted to individual continents