A beta-1,3-glucanase was detected, using laminarin as substrate, in the culture broth of Chaetomium sp. Major activity was associated with a 70 kDa protein band visualized on a polyacrylamide gel. beta-1,3-Glucanase was purified by a one-step, native gel purification procedure. Optimal activity was observed at pH 6.0 and 30 degrees C (over 30 min). It could degrade cell walls of plant pathogens including Rhizoctonia solani, Gibberella zeae, Fusarium sp., Colletotrichum gloeosporioides and Phoma sp. The N-terminal amino acid residues of the purified beta-1,3-glucanase are PYQLQTP, which do not exhibit homology to other fungal beta-1,3-glucanases suggesting it may be a novel enzyme.

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Numerous research results have suggested that the events occurred in a selected cell target and the fates of the cells are spatiotemporally regulated. It has been paying much attention to study the cell events with spatiotemporal proposal designation and analysis. We have been tracking and thinking the new scientific area for many years. Spatiotemporal cell biology and its schematic frame, triple W (when, where, which), are systemically introduced in this study. The triple W under pathological conditions is also discussed.J. Cell. Physiol. 227: 1787-1790, 2012. ß 2011 Wiley Periodicals, Inc.Recent research results suggested that the events occurred in a selected cell and the fate of the cell must be regulated spatiotemporally. We named this new scientific area as ''Spatiotemporal Cell Biology,'' and concluded a schematic frame, triple W, to describe it [Hou et al., 2011]. Numerous research results indicate that an event of cell(s) in a selected cell community must be exactly forwarded to be initiated or inhibited at a correct time point in a right development stage.Understanding from a macro view, the cell community in that the target cell resides must be selected first. Some research articles about the spatiotemporal regulation in cell biology were published together with an introduction in November 2009 [Hurtley, 2009]. Triple W includes When, Where, and Which, and means that an organ, a cell community, a cell, a event must be targeted to be initiated, promoted, inhibited, or stopped at right time and in right place. The events include cell proliferation, differentiation, death, isoform replacement, gene expression, molecular interaction, and others. Under physiological conditions, triple W determines the livelong process for a body from its formation to death (Fig. 1).When will an individual target be selected, changed, or regulated? ''When'' means the different stages and the different time points in a stage that is controlled by the community/body in that the target resides. ''When'' is the first selection that any event in spatiotemporal cell biology must follow with, and numerous reported results have indicated its importance for any event occurrence in any type of tissue or cell at any step of gene expressing, signaling, or cell acting. Diffley et al. [1994] observed the yeast replication origins existed in two chromatin states during the cell cycle, and found that the integration of chromosomal DNA replication into the eukaryotic cell cycle might involve temporal regulation of interactions between cellular factors and replication origins. Both extracellular matrix (ECM) proteins' modulation on their resident cells' biology to match the needs of body and the signals' interaction with their intracellular targets take place at the right time and in the right place [Hynes, 2009;Scott1 and Pawson, 2009]. Such a precise time-scale can be observed in each cell cycle step, even in many types of molecular interaction. A putative spindle matrix can be assembled by spindle assembly checkpoint (SAC) proteins and ...

ANXA2, a member of the annexin family, is overexpressed and plays important roles in tumor development. However, the significance of ANXA2 expression in gastric carcinoma has not been clarified.To elucidate its roles in growth of gastric cancer, ANXA2 expression in SGC-7901 cells was inhibited with a designated siRNA, then cell proliferation, cell cycling, apoptosis and motility were determined by MTT assay, flow cytometry, Hoechst 33342 staining and wound healing assay, respectively. To further assess the behavior of ANXA2 deleted SGC-7901 cells, changes of microstructures were observed under fluorescence microscopy, laser scanning confocal microscopy and electron microscopy. We found that inhibition of ANXA2 expression caused cell proliferation to decrease significantly with G1 arrest, motility to be reduced with changes in pseudopodia/filopodia structure and F-actin and β-tubulin expression, and apoptosis to be enhanced albeit without significance. At the same time, ANXA2 deletion resulted in fewer pseudopodia/filopodia, non-stained areas were increased, contact inhibition among cells reappeared, and expression of F-actin and β-tubulin was decreased, with induction of polymerized disassembled forms. Taken together, these data suggest that ANXA2 overexpression is important to maintain the malignancy of cancer cells, and this member of the annexin family has potential to be considered as a target for the gene therapy of gastric carcinoma.