Cell shape is controlled by the submembranous cortex, an actomyosin network mainly generated by two actin nucleators: the Arp2/3 complex and the formin mDia1. Changes in relative nucleator activity may alter cortical organization, mechanics and cell shape. Here we investigate how nucleation-promoting factors mediate interactions between nucleators.
View Article and Find Full Text PDFThe 2015 Zika virus (ZIKV) outbreak caused global concern when it was determined to cause microcephaly, hearing loss, and other neurodevelopmental manifestations upon fetal exposure. Significant progress has been made in our understanding of the interactions between ZIKV and the pregnant host, but there is still a critical need to understand how ZIKV and other neurotropic viruses affect fetal neurodevelopment. Diaphanous-related formins (Diaphs) have recently been identified as microcephaly-associated proteins in humans and mice.
View Article and Find Full Text PDFA new biochemical analysis has revealed that the Rickettsia bacterial protein Sca2--recently shown to be essential for virulence and actin-dependent motility--assembles actin filaments using a mechanism that functionally resembles the processive elongation tactics used by formins.
View Article and Find Full Text PDFWe examined the role of the actin nucleation promoters neural Wiskott-Aldrich syndrome protein (N-WASP) and WAVE2 in cell protrusion in response to epidermal growth factor (EGF), a key regulator in carcinoma cell invasion. We found that WAVE2 knockdown (KD) suppresses lamellipod formation and increases filopod formation, whereas N-WASP KD has no effect. However, simultaneous KD of both proteins results in the formation of large jagged protrusions with lamellar properties and increased filopod formation.
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