Biological Consequences of Priming Phosphorylation in Cancer Development

Multisite phosphorylations on a single polypeptide mediated by protein kinase(s) are commonly observed. In some cases, hierarchical phosphorylations occur when first priming event triggers second processive phosphorylation. Hierarchal multisite phosphorylation that is mediated by a priming kinase and a processive kinase is a fail-safe system that accurately regulates physiological processes, including cell cycle progression, survival, migration, metabolism, differentiation and stem cell renewal. Here, we summarize the findings of cancer-associated priming kinases (CK1 and DYRK family) and processive kinase (GSK3). GSK3 has an unusual ability to accurately regulate the wide variety of cellular processes via the priming phosphorylation of its substrates. Therefore, dysregulation of priming phosphorylation gives rise to pathological disorders such as cancer

Isolation and characterization of aerobic microorganisms with cellulolytic activity in the gut of endogeic earthworms

The ability of earthworms to decompose lignocellulose involves the assistance of microorganisms in their digestive system. While many studies have revealed a diverse microbiota in the earthworm gut, including aerobic and anaerobicmicroorganisms, it remains unclear which of these species contribute to lignocellulose digestion. In this study, aerobicmicroorganisms with cellulolytic activity isolated from the gut of two endogeic earthworms, Amynthas heteropoda (Megascolecidae) and Eisenia fetida (Lumbricidae) were isolated by solid culture of gut homogenates using filter paper as acarbon source. A total of 48 strains, including four bacterial and four fungal genera, were isolated from two earthworm species. Characterization of these strains using enzyme assays showed that the most representative ones had exocellulase andxylanase activities, while some had weak laccase activity. These findings suggest that earthworms digest lignocellulose byexploiting microbial exocellulase and xylanase besides their own endocellulase. Phylogenetic analysis showed that among thecellulolytic isolates in both earthworm species Burkholderia and Chaetomium were the dominant bacterial and fungal members.[Int Microbiol 2012; 15(3):121-130

Hyper-elliptic Nambu flow associated with integrable maps

We study hyper-elliptic Nambu flows associated with some $n$ dimensional maps and show that discrete integrable systems can be reproduced as flows of this class.Comment: 13 page

A Hamiltonian Flows Associated with Two Dimensional Map

For a given differentiable map $(x,y)\to (X(x,y),Y(x,y))$, which has an inverse, we show that there exists a Hamiltonian flow in which x plays the role of the time variable while y is fixed.Comment: 4 page

Phospholipase Cδ4 is required for Ca2+ mobilization essential for acrosome reaction in sperm

Zona pellucida (ZP)–induced acrosome reaction in sperm is a required step for mammalian fertilization. However, the precise mechanism of the acrosome reaction remains unclear. We previously reported that PLCδ4 is involved in the ZP-induced acrosome reaction in mouse sperm. Here we have monitored Ca2+ responses in single sperm, and we report that the [Ca2+]i increase in response to ZP, which is essential for driving the acrosome reaction in vivo, is absent in PLCδ4−/− sperm. Progesterone, another physiological inducer of the acrosome reaction, failed to induce sustained [Ca2+]i increases in PLCδ4−/− sperm, and consequently the acrosome reaction was partially inhibited. In addition, we observed oscillatory [Ca2+]i increases in wild-type sperm in response to these acrosome inducers. Calcium imaging studies revealed that the [Ca2+]i increases induced by exposure to ZP and progesterone started at different sites within the sperm head, indicating that these agonists induce the acrosome reaction via different Ca2+ mechanisms. Furthermore, store-operated channel (SOC) activity was severely impaired in PLCδ4−/− sperm. These results indicate that PLCδ4 is an important enzyme for intracellular [Ca2+]i mobilization in the ZP-induced acrosome reaction and for sustained [Ca2+]i increases through SOC induced by ZP and progesterone in sperm