Details

Autor(en) / Beteiligte

• Truttmann, Matthias C
• Guye, Patrick
• Dehio, Christoph
• Chakravortty, Dipshikha

Titel

BID-F1 and BID-F2 domains of Bartonella henselae effector protein BepF trigger together with BepC the formation of invasome structures

Ist Teil von

• PloS one, 2011-10, Vol.6 (10), p.e25106-e25106

Ort / Verlag

United States: Public Library of Science

Erscheinungsjahr

2011

Quelle

MEDLINE

Beschreibungen/Notizen

• The gram-negative, zoonotic pathogen Bartonella henselae (Bhe) translocates seven distinct Bartonella effector proteins (Beps) via the VirB/VirD4 type IV secretion system (T4SS) into human cells, thereby interfering with host cell signaling [1], [2]. In particular, the effector protein BepG alone or the combination of effector proteins BepC and BepF trigger massive F-actin rearrangements that lead to the establishment of invasome structures eventually resulting in the internalization of entire Bhe aggregates [2], [3]. In this report, we investigate the molecular function of the effector protein BepF in the eukaryotic host cell. We show that the N-terminal [E/T]PLYAT tyrosine phosphorylation motifs of BepF get phosphorylated upon translocation but do not contribute to invasome-mediated Bhe uptake. In contrast, we found that two of the three BID domains of BepF are capable to trigger invasome formation together with BepC, while a mutation of the WxxxE motif of the BID-F1 domain inhibited its ability to contribute to the formation of invasome structures. Next, we show that BepF function during invasome formation can be replaced by the over-expression of constitutive-active Rho GTPases Rac1 or Cdc42. Finally we demonstrate that BID-F1 and BID-F2 domains promote the formation of filopodia-like extensions in NIH 3T3 and HeLa cells as well as membrane protrusions in HeLa cells, suggesting a role for BepF in Rac1 and Cdc42 activation during the process of invasome formation.