The C-terminal domain of EFA6A interacts directly with F-actin and assembles F-actin bundles

Abstract

The Arf6-specific exchange factor EFA6 is involved in the endocytic/recycling pathway for different cargos. In addition EFA6 acts as a powerful actin cytoskeleton organizer, a function required for its role in the establishment of the epithelial cell polarity and in neuronal morphogenesis. We previously showed that the C-terminus of EFA6 (EFA6-Ct) is the main domain which contributes to actin reorganization. Here, by in vitro and in vivo experiments, we sought to decipher, at the molecular level, how EFA6 controls the dynamic and structuring of actin filaments. We showed that EFA6-Ct interferes with actin polymerization by interacting with and capping actin filament barbed ends. Further, in the presence of actin mono-filaments, the addition of EFA6-Ct triggered the formation of actin bundles. In cells, when the EFA6-Ct was directed to the plasma membrane, as is the case for the full-length protein, its expression induced the formation of membrane protrusions enriched in actin cables. Collectively our data explain, at least in part, how EFA6 plays an essential role in actin organization by interacting with and bundling F-actin.

Arf6 Regulates Endocytosis and Angiogenesis by Promoting Filamentous Actin Assembly

“…Loss of Arf6 significantly shifted the total cellular actin pool to a predominantly globular state, suggesting a lack of F-actin content. This result is in line with Arf6's previously established role as a positive regulator of actin polymerization [49][50][51]. With such a dramatic reduction in actinrelated processes, it would be interesting to know how long-term inhibition of Arf6 would impact established blood vessel homeostasis and related cytoskeletal signaling.…”

Arf6 is required for endocytosis and filamentous actin assembly during angiogenesis in vitro

“…This result is in line with Arf6's previously established role as a positive regulator of actin polymerization. [52][53][54] With such a dramatic reduction in actinrelated processes, it would be interesting to know how long-term inhibition of Arf6 would impact established blood vessel homeostasis and related cytoskeletal signaling.…”

Electrical Detection of Singlet Fission in Single Crystal Tetracene Transistors

“…[1][2][3][4] Spin-dependent processes play a crucial role in determining and enhancing the efficiency of organic-based devices such as organic light emitting diodes (OLEDs) and organic photovoltaics (OPVs). [3][4][5][6][7] Among the most widely used methods for studying spin-dependent processes in organic-based devices is the application of an externally applied magnetic field. 3,4,[7][8][9][10][11] An applied external magnetic field is known to perturb the ratio of singlet and triplet excited states, resulting in changes of the electronic and optoelectronic properties of the organic-based devices such as electrical resistance and electroluminescence.…”