Protected area characteristics that help waterbirds respond to climate warming.

Protected area networks help species respond to climate warming. However, the contribution of a site's environmental and conservation-relevant characteristics to these responses is not well understood. We investigated how composition of nonbreeding waterbird communities (97 species) in the European Union Natura 2000 (N2K) network (3018 sites) changed in response to increases in temperature over 25 years in 26 European countries. We measured community reshuffling based on abundance time series collected under the International Waterbird Census relative to N2K sites' conservation targets, funding, designation period, and management plan status. Waterbird community composition in sites explicitly designated to protect them and with management plans changed more quickly in response to climate warming than in other N2K sites. Temporal community changes were not affected by the designation period despite greater exposure to temperature increase inside late-designated N2K sites. Sites funded under the LIFE program had lower climate-driven community changes than sites that did not received LIFE funding. Our findings imply that efficient conservation policy that helps waterbird communities respond to climate warming is associated with sites specifically managed for waterbirds.

Las redes de áreas protegidas ayudan a las especies a responder al calentamiento climático. Sin embargo, se sabe muy poco sobre la contribución de las características ambientales y relevantes para la conservación de un sitio a estas respuestas. Investigamos cómo la composición de las comunidades no reproductivas de aves acuáticas (97 especies) en la red (3,018 sitios) Natura 2000 de la Unión Europea (N2K) cambió en respuesta a los incrementos de la temperatura durante más de 25 años en 26 países europeos. Medimos la reorganización comunitaria con base en series temporales de abundancia recolectadas durante el Censo Internacional de Aves Acuáticas en relación con los objetivos de conservación de los sitios N2K, el periodo de asignación de fondos y el estado del plan de manejo. La composición comunitaria de las aves acuáticas en los sitios con planes de manejo y designados explícitamente para su protección cambió más rápidamente en respuesta al calentamiento climático que en otros sitios N2K. Los cambios comunitarios temporales no se vieron afectados por el periodo de asignación a pesar de una mayor exposición al incremento de la temperatura dentro de los sitios N2K de asignación tardía. Los sitios financiados por el programa LIFE tuvieron menos cambios comunitarios causados por el clima que los sitios que no recibieron este financiamiento. Nuestros hallazgos sugieren que la política de conservación eficiente que ayuda a las comunidades de aves acuáticas a responder al calentamiento climático está asociada con sitios específicamente gestionados para las aves acuáticas.

Benefits of protected areas for nonbreeding waterbirds adjusting their distributions under climate warming.

Climate warming is driving changes in species distributions and community composition. Many species have a so-called climatic debt, that is, shifts in range lag behind shifts in temperature isoclines. Inside protected areas (PAs), community changes in response to climate warming can be facilitated by greater colonization rates by warm-dwelling species, but also mitigated by lowering extirpation rates of cold-dwelling species. An evaluation of the relative importance of colonization-extirpation processes is important to inform conservation strategies that aim for both climate debt reduction and species conservation. We assessed the colonization-extirpation dynamics involved in community changes in response to climate inside and outside PAs. To do so, we used 25 years of occurrence data of nonbreeding waterbirds in the western Palearctic (97 species, 7071 sites, 39 countries, 1993-2017). We used a community temperature index (CTI) framework based on species thermal affinities to investigate species turnover induced by temperature increase. We determined whether thermal community adjustment was associated with colonization by warm-dwelling species or extirpation of cold-dwelling species by modeling change in standard deviation of the CTI (CTISD ). Using linear mixed-effects models, we investigated whether communities in PAs had lower climatic debt and different patterns of community change than communities outside PAs. For CTI and CTISD combined, communities inside PAs had more species, higher colonization, lower extirpation, and lower climatic debt (16%) than communities outside PAs. Thus, our results suggest that PAs facilitate 2 independent processes that shape community dynamics and maintain biodiversity. The community adjustment was, however, not sufficiently fast to keep pace with the large temperature increases in the central and northeastern western Palearctic. Our results underline the potential of combining CTI and CTISD metrics to improve understanding of the colonization-extirpation patterns driven by climate warming.

Beneficios de las Áreas Protegidas para las Aves Acuáticas No Reproductoras que Están Ajustando su Distribución Debido al Calentamiento Climático Resumen El calentamiento climático está generando cambios en la distribución y en la composición comunitaria de las especies. Muchas de ellas tienen una deuda climática, es decir, los cambios en la distribución se atrasan con respecto a los cambios en las isoclinas térmicas. Dentro de las áreas protegidas (APs), los cambios comunitarios como respuesta al calentamiento climático pueden facilitarse mediante tasas mayores de colonización por especies de climas cálidos, pero también pueden mitigarse al reducir las tasas de extirpación de las especies de climas fríos. Se requiere una evaluación de la importancia relativa de los procesos de colonización-extirpación para orientar las estrategias de conservación que buscan la reducción de la deuda climática y la conservación de las especies. Analizamos las dinámicas de colonización-extirpación que participan en los cambios comunitarios como respuesta al clima dentro y fuera de las APs. Para realizar lo anterior, usamos datos tomados durante 25 años de la presencia de aves acuáticas no reproductoras en el Paleártico occidental (97 especies, 7,071 sitios, 39 países, 1993-2017). Usamos un marco de trabajo del índice de temperatura comunitaria (ITC) basado en las afinidades térmicas de las especies para así investigar la rotación de especies inducida por el incremento en la temperatura. Determinamos si el ajuste térmico en la comunidad estuvo asociado con la colonización por especies de climas cálidos o con la extirpación de especies de climas fríos al modelar el cambio mediante una desviación estándar del ITC (ITCDS ). Con los modelos lineales de efectos mixtos investigamos si las comunidades dentro de las APs tenían una deuda climática más baja y patrones diferentes de cambio comunitario que las comunidades localizadas fuera de las APs. Con la combinación del ITC y deL ITCDS , las comunidades dentro de las APs tuvieron más especies, una mayor colonización, una menor extirpación y una deuda climática más baja (16%) que las comunidades fuera de las APs. Por lo tanto, nuestros resultados sugieren que las APs facilitan dos procesos independientes que moldean las dinámicas comunitarias y mantienen la biodiversidad. Sin embargo, el ajuste comunitario no fue lo suficientemente rápido para mantener el paso de los grandes incrementos en la temperatura de las regiones central y noreste del Paleártico occidental. Nuestros resultados resaltan el potencial que tiene la combinación de las medidas del ITC y del ICTDS para mejorar el entendimiento de los patrones de colonización-extirpación causados por el calentamiento climático.

Expression of neuregulin 4 splice variants in normal human tissues and prostate cancer and their effects on cell motility.

The neuregulin 4 gene encodes at least five different variants (designated A1, A2, B1, B2 and B3) produced as a result of alternative splicing. We have determined their sites of expression in normal human adult tissues using isoform-specific antibodies. Their expression is cell type specific and differs in subcellular location suggesting that they may have varied functions in these contexts. We have shown in a panel of prostate cancers that each form is present to differing degrees, and that principal component analysis indicates that there are three patterns of expression. Some isoforms were positively correlated with high prostate-specific antigen levels and others were inversely associated with Gleason score. Synthetic, refolded A forms promoted lamellipodia and filopodia formation in cells expressing the ErbB4 (CTa) receptor and stimulated cell motility in wound healing assays. The data suggest that the different forms have varied sites of expression and function, and this includes effects on cell architecture and motility.

Identification and characterization of novel spliced variants of neuregulin 4 in prostate cancer.

PURPOSE: The neuregulin (NRG) 1, 2, and 3 genes undergo extensive alternative mRNA splicing, which results in variants that show structural and functional diversity. The aims of this study were to establish whether the fourth member of this family, NRG4, is expressed in prostate cancer, if it is alternatively spliced and whether any functional differences between the variants could be observed. EXPERIMENTAL DESIGN: The expression of NRG4 was determined using immunohistochemical staining of 40 cases of primary prostate cancer. Bioinformatic analysis and reverse transcription-PCR (RT-PCR) using NRG4 isotype-specific primers on a panel of normal and prostate cancer cell lines were used to identify alternatively spliced NRG4 variants. Expression of these variants was determined using isotype-specific antibodies. Transfection into Cos-7 cells of two of these green fluorescent protein-tagged variants allowed analysis of their subcellular location. Four of the variants were chemically synthesized and tested for their ability to activate the ErbB4 receptor. RESULTS: NRG4 was variably expressed in the cytoplasm in the majority of prostate cancer cases, and in a subset of cases in the membrane, high levels were associated with advanced disease stage. Four novel NRG4 splice variants (NRGA2, NRG4 B1-3) were characterized, where each seemed to have a different subcellular location and were also expressed in the cytoplasm of the prostate tumors. NRG4 B3 was also present in endothelial cells. In transfected cells, the A type variant (NRG4 A1) was localized to the membrane, whereas the B type variant (NRG4 B1), which lacks the predicted transmembrane region, had an intracellular localization. Only the variants with an intact epidermal growth factor-like domain activated ErbB4 signaling. CONCLUSION: NRG4 overexpression is associated with advanced-stage prostate cancer. The alternative splice variants may have different roles in cell signaling, some acting as classic receptor ligands and some with as-yet unknown functions.