Cell adhesion-dependent membrane trafficking of a binding partner for the ebolavirus glycoprotein is a determinant of viral entry.
Ebolavirus is a hemorrhagic fever virus associated with high mortality. Although much has been learned about the viral lifecycle and pathogenesis, many questions remain about virus entry. We recently showed that binding of the receptor binding region (RBR) of the ebolavirus glycoprotein (GP) and infection by GP pseudovirions increase on cell adhesion independently of mRNA or protein synthesis. One model to explain these observations is that, on cell adhesion, an RBR binding partner translocates from an intracellular vesicle to the cell surface. Here, we provide evidence for this model by showing that suspension 293F cells contain an RBR binding site within a membrane-bound compartment associated with the trans-Golgi network and microtubule-organizing center. Consistently, trafficking of the RBR binding partner to the cell surface depends on microtubules, and the RBR binding partner is internalized when adherent cells are placed in suspension. Based on these observations, we reexamined the claim that lymphocytes, which are critical for ebolavirus pathogenesis, are refractory to infection because they lack an RBR binding partner. We found that both cultured and primary human lymphocytes (in suspension) contain an intracellular pool of an RBR binding partner. Moreover, we identified two adherent primate lymphocytic cell lines that bind RBR at their surface and strikingly, support GP-mediated entry and infection. In summary, our results reveal a mode of determining viral entry by a membrane-trafficking event that translocates an RBR binding partner to the cell surface, and they suggest that this process may be operative in cells important for ebolavirus pathogenesis (e.g., lymphocytes and macrophages).
Dube
Derek
D
Department of Microbiology, University of Virginia, Charlottesville, VA 22908, USA.
Schornberg
Kathryn L
KL
Shoemaker
Charles J
CJ
Delos
Sue E
SE
Stantchev
Tzanko S
TS
Clouse
Kathleen A
KA
Broder
Christopher C
CC
White
Judith M
JM
D001402:B-Lymphocytes / Q000502:physiology / Q000821:virology; D001665:Binding Sites; D002448:Cell Adhesion / Q000502:physiology; D002460:Cell Line; D002462:Cell Membrane / Q000502:physiology / Q000821:virology; D029043:Ebolavirus / Q000472:pathogenicity* / Q000502:physiology*; D054884:Host-Pathogen Interactions / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D019169:Jurkat Cells; D008214:Lymphocytes / Q000502:physiology* / Q000821:virology*; D008869:Microtubule-Associated Proteins / Q000502:physiology; D010940:Plant Proteins / Q000502:physiology; D011991:Receptors, Virus / Q000502:physiology; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000502:physiology*; D053586:Virus Internalization; D021601:trans-Golgi Network / Q000502:physiology
D008869:Microtubule-Associated Proteins; D010940:Plant Proteins; D011991:Receptors, Virus; D014759:Viral Envelope Proteins; C113189:envelope glycoprotein, Ebola virus; C119741:microtububle assembly protein 49, Nicotiana tabacum
J Virol. 2001 Jun;75(11):5205-14
11333902
J Virol. 2009 Apr;83(7):2883-91
19144707
Proc Natl Acad Sci U S A. 1997 Dec 23;94(26):14764-9
9405687
Biochem J. 1994 Jun 15;300 ( Pt 3):743-9
8010955
J Virol. 2008 Jul;82(14):7238-42
18448524
Blood. 2001 Feb 15;97(4):1027-34
11159533
J Virol. 2001 Nov;75(22):11025-33
11602743
Lab Invest. 2000 Feb;80(2):171-86
10701687
Immunol Lett. 2002 Mar 1;80(3):169-79
11803049
Nat Cell Biol. 2007 Dec;9(12):1381-91
18026091
J Cell Sci. 1999 Jan;112 ( Pt 1):21-33
9841901
Proc Natl Acad Sci U S A. 2009 May 12;106(19):8003-8
19416892
Future Virol. 2009;4(6):621-635
20198110
Virol J. 2009 Jun 08;6:75
19505320
J Virol. 2005 Jan;79(2):918-26
15613320
Curr Opin Cell Biol. 2007 Oct;19(5):529-33
17923403
J Virol. 2004 Jul;78(14):7344-51
15220407
J Biol Chem. 2006 Jun 9;281(23):15951-8
16595665
Viral Immunol. 2004;17(3):390-400
15357905
Nat Rev Immunol. 2005 Jul;5(7):546-59
15965491
Methods Cell Biol. 1989;31:25-43
2550739
J Virol. 2006 Apr;80(8):4174-8
16571833
Science. 2005 Jun 10;308(5728):1643-5
15831716
FASEB J. 2006 Dec;20(14):2519-30
17023517
J Virol. 1998 Apr;72(4):3155-60
9525641
J Cell Biol. 1998 Dec 14;143(6):1485-503
9852146
J Virol. 2007 Dec;81(24):13378-84
17928356
Am J Pathol. 2003 Dec;163(6):2371-82
14633609
J Virol Methods. 2010 Feb;163(2):336-43
19879300
J Biol Chem. 1999 Mar 26;274(13):8779-87
10085119
Am J Physiol Renal Physiol. 2000 Feb;278(2):F317-26
10662736