Novel isoforms of CaBP 33/37 (annexin V) from mammalian brain: structural and phosphorylation differences that suggest distinct biological roles.

Two calcium-dependent phospholipid- and membrane-binding proteins have been purified from bovine brain. These are termed CaBP33 and CaBP37. Complete sequence analysis has revealed that these two proteins are isoforms of annexin V. Despite an apparent difference of 4 kDa between the two proteins on SDS-PAGE, only two amino-acid substitutions were found. These are, in CaBP33, Ser-36 and Lys-125 and in CaBP37, Thr-36 and Glu-125. This corresponds to a mass difference of 15 Da. This was confirmed by electrospray mass spectrometric analysis. Both isoforms can be phosphorylated substoichiometrically in vitro by protein kinase C at residue Thr-22.     

A spatial vascular transcriptomic,proteomic, and phosphoproteomic atlas unveils an angiocrine Tie–Wnt signaling axis in the liver

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The ant fauna of Castelporziano Presidential Reserve (Rome,Italy) as a model for the analysis of ant community structure in relation to environmental variation in Mediterranean ecosystems

Ants are often used as ecological indicators in environmental monitoring programs, but rarely in Europe, probably because of a lack of baseline knowledge on the relationship between ant community structure and environmental variation. We present this baseline knowledge for Italian ecosystems that are typical of the Mediterranean climate, in order to assess the value of ants as ecological indicators in this biogeographic zone. Sampling areas were selected inside the Castelporziano Natural Reserve (Rome, Italy). The elevated variety of habitats and diverse ecological conditions, as well as the different levels of human impact in the Reserve, make this area a suitable location to develop and test biological indicators of environmental quality. The ant community structure was compared among several Mediterranean ecosystems using pitfall trapping, multidimensional scaling, the indicator species analysis and the Functional Groups Approach. Key factors for differences in ant community structure seem to be the presence/absence of water, the level of light and microhabitat diversity. Our results suggest that Castelporziano is an informative area in order to develop a study model for the Italian ant fauna and the Functional Group Approach is a promising procedure to associate differences in ant community structures with differences in habitat stress and disturbance.     

Parsimony analysis of endemicity describes but does not explain: an illustrated critique

Aim To demonstrate that parsimony analysis of endemicity (PAE) is not analogous to a cladistic biogeographical analysis. Location We used six data sets from previously published studies from around the world. Methods In order to test the efficiency of PAE in recovering historical relationships among areas, we performed an empirical comparison of nodes recovered with PAE, primary Brooks parsimony analysis (BPA), and an event‐based method using three models (maximum codivergence, reconciled trees, and the default model of the treefitter program) for six data sets. We measured the performance of PAE in recovering historical area relationships by counting the number and examining the content of nodes recovered by PAE and by historical methods. The dispersal/vicariance ratio was calculated to assess the prevalence of dispersal or vicariance in each reconstruction and its relationship to the performance of PAE. Results Our results show that PAE recovers an average of 17.25% of historical nodes. PAE and BPA tend to provide similar results; however, in relation to the event‐based models, PAE performance was poor under all the tested scenarios. Although in some cases PAE reconstructions are more resolved than historical reconstructions, this does not necessarily mean that PAE produces more informative answers. These additional nodes correspond to unsupported statements that are based solely on the distributional data of taxa and not on their phylogenetic history. In other words, these nodes were not found by the historical methods, which take phylogenetics into account. The number of historical nodes recovered using PAE was in general negatively correlated with the dispersal/vicariance ratio. Main conclusions Our results show that PAE is unable to recover historical patterns and therefore does not fit into the current paradigm of historical biogeography. These findings raise doubts regarding conclusions derived from biogeographical studies that interpret PAE trees as area cladograms. We acknowledge that PAE aims to describe but does not explain the current distribution of organisms. It is therefore a useful tool in other biogeographical or ecological analyses for exploring the distribution of taxa or for establishing hypotheses of primary homology between areas.