A nucleator arms race: cellular control of actin assembly

Campellone, Kenneth; Welch, Matthew D.

doi:10.1038/nrm2867

Cited by 854 publications

(946 citation statements)

References 161 publications

(247 reference statements)

Supporting

Mentioning

931

Contrasting

Unclassified

Order By: Relevance

“…Branched actin networks in lymphocytes are also regulated by the cortactin-like protein HCLS1. HCLS1 is a weak activator of ARP2/3; however, it stabilizes ARP2/3 against debranching 10 . HCLS1 is phosphorylated after BCR stimulation and is required for B cell responses to antigens 70 , although its precise connection to BCR pathways and role in actin dynamics in B cells are not known.…”

Section: [H1] Structure Of the Cortical Cytoskeletonmentioning

confidence: 99%

“…Two types of nucleation factors are responsible for the generation of new actin filaments in all cells, the ARP2/3 complex and formins ( Fig. 1) 10 . The ARP2/3 complex binds to the side of an existing actin filament and nucleates a daughter filament branching at an oblique angle.…”

Section: [H1] Structure Of the Cortical Cytoskeletonmentioning

confidence: 99%

“…The second major ubiquitous activator of ARP2/3 is the WAVE complex 10 . In B cells, the WAVE complex is composed of WASF2 and four other proteins (CYFIP2, NCKAP1L, ABI1, BRK1) 66 .…”

Section: [H1] Structure Of the Cortical Cytoskeletonmentioning

confidence: 99%

“…The unique property of the WAVE complex is that it produces spreading arcs of branched actin polymerization, which promote the formation of lamellipodia 67,68 . The WAVE complex is activated by RAC GTPases via VAV proteins and by binding to PIP3 at the plasma membrane 10 .…”

Section: [H1] Structure Of the Cortical Cytoskeletonmentioning

confidence: 99%

See 3 more Smart Citations

Cytoskeletal control of B cell responses to antigens

Tolar

2017

Nat Rev Immunol

125

View full text Add to dashboard Cite

The actin cytoskeleton is essential for cell mechanics and has increasingly been implicated in the regulation of cell signalling. In B cells, the actin cytoskeleton couples extensively to B cell receptor (BCR) signalling pathways and its defects can either enhance or suppress B cell activation. Recent insights from single-cell imaging and biophysical techniques suggest that actin orchestrates BCR signalling at the plasma membrane through effects on protein diffusion, and that it regulates antigen discrimination through the biomechanics of immune synapses. These mechanical functions also play a role in the adaptation of B cell subsets to specialized tasks during antibody responses.3

show abstract

Section: [H1] Structure Of the Cortical Cytoskeletonmentioning

confidence: 99%

Section: [H1] Structure Of the Cortical Cytoskeletonmentioning

confidence: 99%

“…The second major ubiquitous activator of ARP2/3 is the WAVE complex 10 . In B cells, the WAVE complex is composed of WASF2 and four other proteins (CYFIP2, NCKAP1L, ABI1, BRK1) 66 .…”

Section: [H1] Structure Of the Cortical Cytoskeletonmentioning

confidence: 99%

Section: [H1] Structure Of the Cortical Cytoskeletonmentioning

confidence: 99%

See 2 more Smart Citations

Cytoskeletal control of B cell responses to antigens

Tolar

2017

Nat Rev Immunol

125

View full text Add to dashboard Cite

show abstract

“…The protrusive force is supplied by polymerisation of actin filaments initiated via the ubiquitous Arp2/3 complex which is activated by nucleation promoting factors (NPFs) (Campellone and Welch, 2010). In mammalian and Drosophila cells, the critical NPF underlying lamellipodium formation is the WRC {WAVE [WASP (WiskottAldrich syndrome protein)-family verprolin-homologous protein] regulatory complex}, which is thought to be activated at the plasma membrane by the Rho GTPase Rac1 (Kunda et al, 2003;Miki et al, 1998).…”

Section: Introductionmentioning

confidence: 99%

The Drosophila Arf1 homologue Arf79F is essential for lamellipodium formation

Humphreys

Liu

Davidson

et al. 2012

Journal of Cell Science

View full text Add to dashboard Cite

SummaryThe WAVE regulatory complex (WRC) drives the polymerisation of actin filaments located beneath the plasma membrane to generate lamellipodia that are pivotal to cell architecture and movement. By reconstituting WRC-dependent actin assembly at the membrane, we recently discovered that several classes of Arf family GTPases directly recruit and activate WRC in cell extracts, and that Arf cooperates with Rac1 to trigger actin polymerisation. Here, we demonstrate that the Class 1 Arf1 homologue Arf79F colocalises with the WRC at dynamic lamellipodia. We report that Arf79F is required for lamellipodium formation in Drosophila S2R+ cells, which only express one Arf isoform for each class. Impeding Arf function either by dominant-negative Arf expression or by Arf doublestranded RNA interference (dsRNAi)-mediated knockdown uncovered that Arf-dependent lamellipodium formation was specific to Arf79F, establishing that Class 1 Arfs, but not Class 2 or Class 3 Arfs, are crucial for lamellipodia. Lamellipodium formation in Arf79F-silenced cells was restored by expressing mammalian Arf1, but not by constitutively active Rac1, showing that Arf79F does not act via Rac1. Abolition of lamellipodium formation in Arf79F-silenced cells was not due to Golgi disruption. Blocking Arf79F activation with guanine nucleotide exchange factor inhibitors impaired WRC localisation to the plasma membrane and concomitant generation of lamellipodia. Our data indicate that the Class I Arf GTPase is a central component in WRC-driven lamellipodium formation.

show abstract

Cytoskeleton Dynamics: Actin in Cell Invasion

Cáceres

Plastino

2017

Encyclopedia of Life Sciences

View full text Add to dashboard Cite

Basement membrane (BM) is a dense sheet of specialised extracellular matrix that separates epithelial layers of cells from the underlying tissue. The penetration of cells through BM barriers, called ‘invasion’, is an important process during normal tissue development and in cancer metastasis. To enable invasion, the cell adopts different shapes and creates different protrusive structures powered mainly by actin cytoskeleton dynamics. However, the exact cytoskeletal strategy that the cell uses to cross the physical BM barrier depends on the physiological context and the physical environment, as observed by examining actin structures in invading cancer and immune cells, and in cells that invade during developmental processes such as angiogenesis and anchor cell invasion in Caenorhabditis elegans . Key Concepts Actin polymerisation and actomyosin contraction can generate cell shape changes such as protrusions. Different actin‐binding proteins produce protrusions of different architecture and function. Shape changes and protrusions are necessary for cell invasion across basement membrane barriers. Cell invasion is observed in pathological and normal developmental contexts. The actin dynamics strategy employed by an invading cell depends on the environment and the physiological context.

show abstract

A nucleator arms race: cellular control of actin assembly

Cited by 854 publications

References 161 publications

Cytoskeletal control of B cell responses to antigens

Cytoskeletal control of B cell responses to antigens

The Drosophila Arf1 homologue Arf79F is essential for lamellipodium formation

Cytoskeleton Dynamics: Actin in Cell Invasion

Contact Info

Product

Resources

About