We use the model to provide

context and summarize what is known about neurogenesis in urchin embryos. We review morphological features of the differentiation phase of neurogenesis and summarize current understanding of neural specification and regulation of proneural networks. Delta-Notch signaling is a common feature of metazoan neurogenesis that produces committed progenitors and it appears to be a critical phase of neurogenesis in urchin embryos. Descriptions of the differentiation phase of neurogenesis indicate a stereotypic sequence of neural differentiation and patterns of axonal growth. Features of neural differentiation are consistent with localized signals guiding growth cones with selleckchem trophic, learn more adhesive, and tropic cues. Urchins are a facile, postgenomic model with the potential of revealing many shared and derived features of deuterostome neurogenesis. genesis 52:208-221. (c) 2014 Wiley Periodicals, Inc.”
“Background: Two distinct

metalloproteinase types (fragilysin and metalloproteinase II/MPII) are encoded by the Bacteroides fragilis pathogenicity island. Results: Our assays determined substrate cleavage characteristics of fragilysin and MPII. Conclusion: MPII is the first zinc metalloproteinase with the dibasic cleavage preferences. Significance: Our results are important for understanding B. fragilis virulence and fundamental roles of the microbiome in human health and disease. Enterotoxigenic anaerobic Bacteroides fragilis is a significant source of inflammatory diarrheal disease and a risk factor for colorectal cancer. Two distinct metalloproteinase Semaxanib clinical trial types (the homologous 1, 2, and 3 isoforms of fragilysin (FRA1, FRA2, and

FRA3, respectively) and metalloproteinase II (MPII)) are encoded by the B. fragilis pathogenicity island. FRA was demonstrated to be important to pathogenesis, whereas MPII, also a potential virulence protein, remained completely uncharacterized. Here, we, for the first time, extensively characterized MPII in comparison with FRA3, a representative of the FRA isoforms. We employed a series of multiplexed peptide cleavage assays to determine substrate specificity and proteolytic characteristics of MPII and FRA. These results enabled implementation of an efficient assay of MPII activity using a fluorescence-quenched peptide and contributed to structural evidence for the distinct substrate cleavage preferences of MPII and FRA. Our data imply that MPII specificity mimics the dibasic ArgArg cleavage motif of furin-like proprotein convertases, whereas the cleavage motif of FRA (Pro-X-X-Leu-(Arg/Ala/Leu)) resembles that of human matrix metalloproteinases. To the best of our knowledge, MPII is the first zinc metalloproteinase with the dibasic cleavage preferences, suggesting a high level of versatility of metalloproteinase proteolysis.