The actin cytoskeleton mediates cellular processes through the dynamic regulation of the time, location, and extent of actin polymerization. Actin polymerization is controlled by several types of evolutionarily conserved proteins, including those comprising the ARP2/3 complex. In animal cells ARP2/3 activity is regulated by WAVE complexes that contain WAVE/SCAR proteins, PIR121, Nap125, and oth...

This report describes two different methodologies for the synthesis of aryl end-functionalized poly(lactide)s (PLAs) catalyzed by indium complexes. In the first method, a series of para-functionalized phenoxy-bridged dinuclear indium complexes [(NNO)InCl]2(μ-Cl)(μ-OPhR) (R = OMe (1), Me (2), H (3), Br (4), NO2 (5)) were synthesized and fully characterized. The solution and solid state structure...

BACKGROUND WASp/SCAR proteins activate the Arp2/3 complex to nucleate actin filament assembly and are thought to have important roles in endocytosis. WASp is required for efficient endocytosis of antigen receptors, N-WASp promotes actin polymerization-dependent movement of endomembrane vesicles, and Las17 (a yeast WASp homolog) is required for endocytic internalization. However, it is unknown w...

Many animal cells initiate crawling by protruding lamellipodia, consisting of a dense network of actin filaments, at their leading edge. We imaged XTC cells that exhibit flat lamellipodia on poly-L-lysine-coated coverslips. Using active contours, we tracked the leading edge and measured the total amount of F-actin by summing the pixel intensities within a 5-μm band. We observed protrusion and r...

Chromatin domains are believed to spread via a polymerization-like mechanism in which modification of a given nucleosome recruits a modifying complex, which can then modify the next nucleosome in the polymer. In this study, we carry out genome-wide mapping of the Sir3 component of the Sir silencing complex in budding yeast during a time course of establishment of heterochromatin. Sir3 localizat...

Living radical polymerization (LRP) of organic and water soluble acrylates and acrylamides was mediated by a versatile cobalt porphyrin complex (TMP-OH)Co. The capability of this cobalt complex to mediate LRP in both polar and non-polar media permits the direct synthesis of useful and previously difficult to prepare functional block copolymers.

polybutadiene nanoparticles were synthesized via batch emulsion polymerization of butadiene in the presence of potassium persulfate, disproportionate rosinate potassium cation and t-dodecyl mercaptane as initiator, emulsifier and chain transfer agent, respectively. polymerization reaction was performed at different temperatures (60, 70 and 80 °c). conversion was measured at the various time int...

Thymosin beta 4 (T beta 4), a 5-kD peptide which binds G-actin and inhibits its polymerization (Safer, D., M. Elzinga, and V. T. Nachmias. 1991. J. Biol. Chem. 266:4029-4032), appears to be the major G-actin sequestering protein in human PMNs. In support of a previous study by Hannappel, E., and M. Van Kampen (1987. J. Chromatography. 397:279-285), we find that T beta 4 is an abundant peptide i...

The activation of the small GTPase RhoA is necessary for ACh-induced actin polymerization and airway smooth muscle (ASM) contraction, but the mechanism by which it regulates these events is unknown. Actin polymerization in ASM is catalyzed by the actin filament nucleation activator, N-WASp and the polymerization catalyst, Arp2/3 complex. Activation of the small GTPase cdc42, a specific N-WASp a...