Ena/VASP proteins contribute to Listeria monocytogenes pathogenesis by controlling temporal and spatial persistence of bacterial actin-based motility.
The Listeria monocytogenes surface protein ActA mediates actin-based motility by interacting with a number of host cytoskeletal components, including Ena/VASP family proteins, which in turn interact with actin and the actin-binding protein profilin. We employed a bidirectional genetic approach to study Ena/VASP's contribution to L. monocytogenes movement and pathogenesis. We generated an ActA allelic series within the defined Ena/VASP-binding sites and introduced the resulting mutant L. monocytogenes into cell lines expressing different Ena/VASP derivatives. Our findings indicate that Ena/VASP proteins contribute to the persistence of both speed and directionality of L. monocytogenes movement. In the absence of the Ena/VASP proline-rich central domain, speed consistency decreased by sixfold. In addition, the Ena/VASP F-actin-binding region increased directionality of bacterial movement by fourfold. We further show that both regions of Ena/VASP enhanced L. monocytogenes cell-to-cell spread to a similar degree, although the Ena/VASP F-actin-binding region did so in an ActA-independent manner. Surprisingly, our ActA allelic series enabled us to uncouple L. monocytogenes speed from directionality although both were controlled by Ena/VASP proteins. Lastly, we showed the pathogenic relevance of these findings by the observation that L. monocytogenes lacking ActA Ena/VASP-binding sites were up to 400-fold less virulent during an adaptive immune response.
Auerbuch
Victoria
V
Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
Loureiro
Joseph J
JJ
Gertler
Frank B
FB
Theriot
Julie A
JA
Portnoy
Daniel A
DA
D000199:Actins / Q000378:metabolism*; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D003598:Cytoskeletal Proteins; D005798:Genes, Bacterial; D008089:Listeria monocytogenes / Q000276:immunology / Q000472:pathogenicity* / Q000502:physiology; D008088:Listeriosis / Q000276:immunology / Q000382:microbiology; D008264:Macrophages / Q000382:microbiology; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008840:Microfilament Proteins; D009068:Movement; D020125:Mutation, Missense; D010750:Phosphoproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017354:Point Mutation; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D051381:Rats; D017384:Sequence Deletion; D014774:Virulence / Q000235:genetics; D000098662:Vasodilator-Stimulated Phosphoprotein
D000199:Actins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D015815:Cell Adhesion Molecules; D003598:Cytoskeletal Proteins; C102176:Enah protein, mouse; D008565:Membrane Proteins; D008840:Microfilament Proteins; D010750:Phosphoproteins; D000098662:Vasodilator-Stimulated Phosphoprotein; C072980:actA protein, Listeria monocytogenes