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Biology subjects

Izadi, M.

Publications and source records attributed to Izadi, M..

2 recordsLinked to original sources

Sanguinarine activates ATM/ATR-mediated CHK-1 signaling to drive p53-dependent apoptosis in the C. elegans germline

Sanguinarine (SNG) is a natural component belonging to the benzophenanthridine alkaloids. In recent years, due to its remarkable biological activities, it has gained wide interest in the pharmaceutical industry. Various studies have reported its potential as a therapeutic agent in treating chronic human diseases such as cancer. SNG is widely reported to cause programmed cell death in various cancer cell lines. The mechanism by which SNG triggers apoptosis remains poorly elucidated, especially in vivo. Previous studies reported that sanguinarine induces apoptosis by increasing reactive oxygen species (ROS). In this study, we aimed to characterize the effects of SNG using an in vivo Caenorhabditis elegans (C. elegans) model. Treating C. elegans with various SNG concentrations resulted in apoptotic cell death in the proliferative germline. Interestingly, SNG-induced apoptosis depends on the core apoptotic machinery initiated by the DNA-damage-induced activity of the p53/CEP-1 protein. We have also demonstrated that the increase in germ cell apoptosis is caused by elevated levels of reactive oxygen species (ROS) following SNG treatment. Notably, the apoptotic phenotype induced by SNG was resolved upon treatment with the ROS scavenger. Altogether, our study demonstrates that SNG increases ROS, leading to activation of DNA damage-induced apoptosis in the proliferative germline of C. elegans.

cancer biology↗

Functional interdependence of the actin nucleator Cobl and Cobl-like in dendritic arbor development

Local actin filament formation is indispensable for development of the dendritic arbor of neurons. We show that, surprisingly, the action of single actin filament-promoting factors was insufficient for powering dendritogenesis. Instead, this process required the actin nucleator Cobl and its only evolutionary distant ancestor Cobl-like acting interdependently. This coordination between Cobl-like and Cobl was achieved by physical linkage by syndapin I. Syndapin I formed nanodomains at convex plasma membrane areas at the base of protrusive structures and interacted with three motifs in Cobl-like, one of which was Ca2+/calmodulin-regulated. Consistently, syndapin I, Cobl-likes newly identified N terminal calmodulin-binding site and the single Ca2+/calmodulin-responsive syndapin-binding motif all were critical for Cobl-likes functions. In dendritic arbor development, local Ca2+/CaM-controlled actin dynamics thus relies on regulated and physically coordinated interactions of different F-actin formation-promoting factors and only together they have the power to bring about the sophisticated neuronal morphologies required for neuronal network formation.

cell biology↗