Ras-related C3 botulinum toxin substrate 1 (Rac1) is a member of the Rho family of GTPases that functions as a molecular switch to regulate many important cellular events including actin cytoskeleton remodeling during neurite outgrowth. Engulfment and cell motility 1 (ELMO1)-dedicator of cytokinesis 1 (DOCK180) is a bipartite guanine nucleotide exchange factor (GEF) complex that has been reported to activate Rac1 on the plasma membrane (PM). Emerging evidence suggests that the small GTPase ADP ribosylation factor 6 (ARF6) activates Rac1 via the ELMO1/DOCK180 complex. However, the exact mechanism by which ARF6 triggers ELMO1/DOCK180-mediated Rac1 signaling remains unclear. Here, we report that the neuronal scaffold protein FE65 serves as a functional link between ARF6 and ELMO1, allowing the formation of a multimeric signaling complex. Interfering with formation of this complex by transfecting either FE65-binding-defective mutants or FE65 siRNA attenuates both ARF6-ELMO1-mediated Rac1 activation and neurite elongation. Notably, the PM trafficking of ELMO1 is markedly decreased in cells with suppressed expression of either FE65 or ARF6. Likewise, this process is attenuated in the FE65-binding-defective mutants transfected cells. Moreover, overexpression of FE65 increases the amount of ELMO1 in the recycling endosome, an organelle responsible for returning proteins to the PM, whereas knockout of FE65 shows opposite effect. Together, our data indicates that FE65 potentiates ARF6-Rac1 signaling by orchestrating ARF6 and ELMO1 to promote the PM trafficking of ELMO1 via the endosomal recycling pathway, and thus, promotes Rac1-mediated neurite outgrowth.
In this paper, we study the corrosion behavior of parylene-metalparylene thin films using accelerated-lifetime soak tests. The samples under test are thin film resistors with a 200 nm layer of Au sandwiched by parylene-C on both sides, fabricated with parylenemetal skin technology. The samples are tested in hot saline both passively and actively, and different failure modes are observed using optical and electron-beam metrologies.Bubbles and delamination are first seen in the samples after 2 days of soaking under passive conditions, and followed by metal corrosion. While under active conditions, either bubbles or parylene breakdowns are observed depending on the thickness of parylene packaging. These results contribute to a better understanding of the failure mechanisms of parylene packaging in body fluids.
The
functional ionic liquids (ILs) [NH2emim][OAc] and [NH2emim][BF4] were synthesized for SO2 capture.
Although functional ILs have potential advantages in SO2 absorption, the high viscosity of a single IL markedly affects the
SO2 absorption separation process. To improve the SO2 absorption performance, [NH2emim][OAc] and [NH2emim][BF4] were mixed with low-viscosity imidazolium-based
ILs [bmim][OH]/[bmim][BF4]. When the mole ratio of [NH2emim][OAc]/[bmim][OH] is about 1:1, the binary mixture has
the best SO2 absorption capacity. The SO2 absorption
performance was investigated in the simulated flue gas, where SO2 partial pressure was about 0.2 kPa. Under the low SO2 partial pressure, the absorption capacity of the [NH2emim][OAc] + [bmim][OH] mixture was more than 0.7 mol of SO2/mol of IL, which was superior to that of a single IL. The
regeneration test of [NH2emim][OAc] + [bmim][OH] showed
that the binary mixture had high reversibility and the SO2 absorption capacity almost kept constant after 12 recycles. The
viscosity and density of the IL mixture changed slightly, which only
have a 2–3% increase in each cycle.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.