The cytoplasmic domain of the poliovirus receptor CD155 associates strongly and specifically with Tctex-1, a light chain of the dynein motor complex, mapping to a SKCSR motif.
The cellular receptor for poliovirus CD155 (or PVR) is the founding member of a new class of membrane-associated immunoglobulin-like proteins, which include the mouse tumor-associated antigen E4 (Tage4) and three proteins termed “nectins.” Using a yeast two-hybrid screen we have discovered that the cytoplasmic domain of CD155 associates strongly and specifically with Tctex-1, a light chain of the dynein motor complex, the latter representing the major driving force for retrograde transport of endocytic vesicles and membranous organelles. We confirmed the interaction biochemically and by co-immunoprecipitation, and we mapped the Tctex-1 binding site to a SKCSR motif within the juxtamembrane region of CD155. Tctex-1 immunoreactivity was detected in mouse sciatic nerve and spinal cord (two tissues of central importance for poliovirus pathogenesis) in punctate, possibly vesicular, patterns. We propose that the cytoplasmic domain may target CD155-containing endocytic vesicles to the microtubular network.Neurotropic viruses like poliovirus, herpesvirus, rabies virus, and pseudorabies virus all utilize neuronal retrograde transport to invade the central nervous system. Association with Tctex-1 and, hence, with the dynein motor complex may offer an explanation for how poliovirus hijacks the cellular transport machinery to retrogradely ascend along the axon to the neuronal cell body. The cellular receptor for poliovirus CD155 (or PVR) is the founding member of a new class of membrane-associated immunoglobulin-like proteins, which include the mouse tumor-associated antigen E4 (Tage4) and three proteins termed “nectins.” Using a yeast two-hybrid screen we have discovered that the cytoplasmic domain of CD155 associates strongly and specifically with Tctex-1, a light chain of the dynein motor complex, the latter representing the major driving force for retrograde transport of endocytic vesicles and membranous organelles. We confirmed the interaction biochemically and by co-immunoprecipitation, and we mapped the Tctex-1 binding site to a SKCSR motif within the juxtamembrane region of CD155. Tctex-1 immunoreactivity was detected in mouse sciatic nerve and spinal cord (two tissues of central importance for poliovirus pathogenesis) in punctate, possibly vesicular, patterns. We propose that the cytoplasmic domain may target CD155-containing endocytic vesicles to the microtubular network. Neurotropic viruses like poliovirus, herpesvirus, rabies virus, and pseudorabies virus all utilize neuronal retrograde transport to invade the central nervous system. Association with Tctex-1 and, hence, with the dynein motor complex may offer an explanation for how poliovirus hijacks the cellular transport machinery to retrogradely ascend along the axon to the neuronal cell body. central nervous system monoclonal antibody glutathioneS-transferase alkaline phosphatase secreted alkaline phosphatase open reading frame neuromuscular junction pseudorabies virus Poliovirus, a member of the genus Enterovirus of Picornaviridae, is a human neurotropic virus that causes poliomyelitis, a disease leading to paralysis or death. Although discovered nearly one hundred years ago, the mechanism by which poliovirus invades the central nervous system (CNS)1and specifically selects motor neurons for destruction remains elusive. Paralytic poliomyelitis is a rare neurologic complication of poliovirus infection (one out of one hundred), as the virus enters humans by ingestion and proliferates largely unnoticed in the gastrointestinal tract. Interestingly, once in the CNS, the virus spares most cells of the CNS parenchyma other than motor neurons from destruction. This unique neurotropism has attracted attention for decades, but no satisfactory explanation has been presented. A major determinant of a virus' pathogenicity is its tissue tropism, which is governed predominantly by the cognate cell surface receptor. The receptor for all three serotypes of poliovirus, CD155 (also known as PVR), is a membrane-associated, single-span glycoprotein belonging to the immunoglobulin superfamily (1Mendelsohn C.L. Wimmer E. Racaniello V.R. Cell. 1989; 56: 855-865Abstract Full Text PDF PubMed Scopus (814) Google Scholar). The CD155 gene expresses four splice variants of which two are membrane-bound (CD155α and δ) and function as poliovirus receptors. CD155β and γ are secreted isoforms lacking a transmembrane domain (2Koike S. Horie H. Ise I. Okitsu A. Yoshida M. Iizuka N. Takeuchi K. Takegami T. Nomoto A. EMBO J. 1990; 9: 3217-3224Crossref PubMed Scopus (270) Google Scholar). Impaired by the apparently exclusive restriction to primates, CD155 is only slowly revealing its physiological functions. CD155 mRNA expression has been detected by Northern blot analyses in brain, small intestine, placenta, heart, skeletal muscle, kidney, lung, and liver (3Ren R. Racaniello V.R. J. Virol. 1992; 66: 296-304Crossref PubMed Google Scholar, 4Koike S. Aoki J. Nomoto A. Wimmer E. Cellular Receptors for Animal Viruses. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY1994: 463-480Google Scholar). Similar albeit not identical expression patterns have been found in transgenic mice expressing the human CD155 gene (5Koike S. Taya C. Kurata T. Abe S. Ise I. Yonekawa H. Nomoto A. Proc. Natl. Acad. Sci. U. S. A. 1991; 88: 951-955Crossref PubMed Scopus (261) Google Scholar,6Ren R. Costantini F. Gorgacz E.J. Lee J.J. Racaniello V.R. Cell. 1990; 63: 353-362Abstract Full Text PDF PubMed Scopus (312) Google Scholar). CD155-tg mice are now well established as a model of human poliomyelitis. Activity of the CD155 promoter in the notochord and floor plate of the developing neural tube of CD155 promoter/LacZ-tg mice suggests that a primary function of CD155 may relate to the development of the CNS during embryogenesis (7Gromeier M. Solecki D. Patel D.D. Wimmer E. Virology. 2000; 273: 248-257Crossref PubMed Scopus (64) Google Scholar). The sites of primary infection and gastroenteric replication of poliovirus are thought to be in tonsillopharyngeal tissue and the Peyer's patches of the small intestine (8Bodian D. Am. J. Hyg. 1956; 64: 181-197PubMed Google Scholar, 9Sabin A. Ward R. J. Exp. Med. 1941; 73: 757-770Crossref PubMed Scopus (7) Google Scholar). The commonality between these structures is their large concentration of lymphatic cells, but, remarkably, the predominant cells supporting poliovirus proliferation in the gastrointestinal tract of an infected individual remain unknown. As aforementioned, poliovirus infections are mainly restricted to the enteric tract. Viremia, however, is a prerequisite for the progression to poliomyelitis. How poliovirus spreads subsequently from the blood to the CNS is poorly understood. Two pathways have been suggested. First, the virus may directly pass from the blood into the CNS by crossing the blood-brain barrier (10Yang W.X. Terasaki T. Shiroki K. Ohka S. Aoki J. Tanabe S. Nomura T. Terada E. Sugiyama Y. Nomoto A. Virology. 1997; 229: 421-428Crossref PubMed Scopus (95) Google Scholar). The second hypothesis suggests that the virus is transported by retrograde axonal transport ascending from the muscle to the spinal cord and brain (11McCloskey B.P. Lancet. 1950; 1: 659-663Abstract Scopus (18) Google Scholar). This hypothesis has found strong support in experiments with CD155-tg mice (12Ohka S. Yang W.X. Terada E. Iwasaki K. Nomoto A. Virology. 1998; 250: 67-75Crossref PubMed Scopus (96) Google Scholar, 13Gromeier M. Wimmer E. J. Virol. 1998; 72: 5056-5060Crossref PubMed Google Scholar, 14Ren R. Racaniello V.R. J. Infect. Dis. 1992; 166: 747-752Crossref PubMed Scopus (133) Google Scholar). The presence of poliovirions in axons during poliomyelitis has been a long observed phenomenon (15Bodian D. Brain. 1940; 63: 135-177Crossref Scopus (26) Google Scholar, 16Fairbrother R.W. Hurst E.W. J. Pathol. Bacteriol. 1930; 33: 17-45Crossref Google Scholar). Ohka and colleagues (12Ohka S. Yang W.X. Terada E. Iwasaki K. Nomoto A. Virology. 1998; 250: 67-75Crossref PubMed Scopus (96) Google Scholar) provided direct evidence of poliovirus in the sciatic nerves of tg mice and showed that during retrograde axonal transport the virus remains in the form of an intact 160 S particle. In this study we have focused on one or more possible functions of the intracellular C-terminal domain of CD155 to decipher cell-internal interactions important for protein function, perhaps related to poliovirus pathogenesis. We have therefore analyzed the C-terminal peptides of CD155α and -δ in a yeast two-hybrid screen. Here we describe the interaction of the cytoplasmic domain of CD155 with Tctex-1, a light chain subunit of the dynein motor complex. Considering the function of dynein as the major driving force for minus end-directed transport along microtubuli, we propose that we have identified a molecular link between poliovirus and the retrograde axonal transport machinery. Indeed, we consider it possible that the majority of poliovirus infection of the CNS leading to destruction of motor neurons may occur via retrograde axonal transport. We discuss our results in light of most recent findings for two other neurotropic viruses, rabies and herpesvirus. COS-1 and HEK 293, and HEK 293T cells, were maintained in Dulbecco's modified Eagle's medium (10% fetal bovine serum and penicillin/streptomycin). Two independently derived affinity-purified anti-Tctex-1 polyclonal antibodies were kindly provided by S. King (R5205, University of Connecticut, Farmingville, CT) and K. Campbell (Fox Chase Cancer Center, Philadelphia, PA) (17Campbell K.S. Cooper S. Dessing M. Yates S. Buder A. J. Immunol. 1998; 161: 1728-1737PubMed Google Scholar, 18King S.M. Dillman 3rd, J.F. Benashski S.E. Lye R.J. J. Full Text Full Text PDF PubMed Scopus Google Scholar). antibodies the chain of and alkaline phosphatase were from In R. J. J. Virol. 66: PubMed Scopus Google Scholar) and as well as J. S. H. Ise I. H. T. M. Nomoto A. Exp. 1997; PubMed Scopus Google Scholar) were in this were and J. T. A Laboratory Cold Spring Harbor Cold Spring Harbor, Scholar). Two for the yeast two-hybrid or were by the region of the cytoplasmic of CD155α or to the domain in the University of of human to the was by the Tctex-1 of in the two-hybrid screen and it into the the CD155α of and the cytoplasmic domain of CD155α or the Tctex-1 region was into 1991; PubMed Scopus Google Scholar). A two was by from the region of human secreted alkaline phosphatase was from into and to the cytoplasmic domain of cell in D. D. PubMed Scopus Google Scholar) was The yeast S.M. Cooper Cell. Full Text PDF PubMed Scopus Google Scholar) was with the and or and lacking and were and for expression by binding of were into E. and The of interaction of the most strongly was by proteins were and as A. F. T. Wimmer E. J. Virol. 1998; 72: PubMed Google Scholar). Tctex-1 protein was from the in system by to the of protein to was with of for the by four with binding proteins were by and by In a second of a cytoplasmic cell of the mouse cell was as a of cells were in of cells was with of protein on for were three with by of the proteins and with polyclonal antibody In a we the of the system with the of of or expression were into HEK of medium of was with of proteins to and for The were four with and the of protein that was to the was as a of Tctex-1 protein of mouse tissues from mice were by of protein were by and by blot with anti-Tctex-1 of on the was by of the with of HEK 293T cells were with of and cells were and as for The of cells was with antibody a antibody or antibodies and we by the of The proteins were analyzed by anti-Tctex-1 mouse spinal cord and sciatic nerve tissues were in mouse were for in were on and in for were with and serum for by with anti-Tctex-1 antibodies (17Campbell K.S. Cooper S. Dessing M. Yates S. Buder A. J. Immunol. 1998; 161: 1728-1737PubMed Google Scholar) a of in of with the were with a of antibody for The were for in and with were on a with a model and with tissue Northern were from The were for with from a the by the system cytoplasmic proteins that with the intracellular of CD155α and were as in a yeast two-hybrid to that R. S. Proc. Natl. Acad. Sci. U. S. A. 1991; 88: PubMed Scopus Google Scholar, S. 1989; PubMed Scopus Google Scholar). The majority of showed expressing of as by binding not of strongly to were of most strongly termed was from yeast and with the or to only with or but not with a As in was detected only in yeast in which and or were was no with or or with and of were the cytoplasmic of CD155 and were provided This that is a strong interaction between the cytoplasmic of CD155α or and the protein in this yeast two-hybrid of gene by domain domain was was for are the of on was in a new for are the of on of the a of to the The open reading frame was of individual of were to the gene which was found to be to the of the complex gene E. M. K. D. Cell. 1989; Full Text PDF PubMed Scopus (95) Google Scholar). and mouse Tctex-1 and along their this study was T. F. S. M. E. Y. Y. 73: PubMed Scopus Google Scholar) the human of mouse Tctex-1, identical to our and it We to the Tctex-1 for the human protein this Tctex-1 was identified as a subunit of the dynein motor complex S.M. Dillman 3rd, J.F. Benashski S.E. Lye R.J. J. Full Text Full Text PDF PubMed Scopus Google Scholar, A. King S.M. J. 1998; PubMed Scopus Google Scholar). in two dynein the major driving force of retrograde transport of membrane-bound and vesicles and is in during on the other is the force for and as is observed in the of or the of the tract Tctex-1 was found to be in of dynein S.M. Dillman 3rd, J.F. Benashski S.E. Lye R.J. J. Full Text Full Text PDF PubMed Scopus Google Scholar, A. King S.M. J. 1998; PubMed Scopus Google Scholar). for the of Tctex-1 mRNA in mice E. M. K. D. Cell. 1989; Full Text PDF PubMed Scopus (95) Google is the expression of Tctex-1, in Northern blot to the expression of the Tctex-1 mRNA in human A to the Tctex-1 detected a to in all tissues The expression of Tctex-1 was observed in skeletal muscle and and the expression was in brain and and This expression that observed in mouse and E. M. K. D. Cell. 1989; Full Text PDF PubMed Scopus (95) Google S.M. E. Dillman 3rd, J.F. Benashski S.E. 1998; PubMed Scopus Google Scholar). CD155-tg mice are a model for the study of poliomyelitis, we were in patterns in the expression of Tctex-1 protein to the patterns observed by Northern blot this we tissue and analyzed mouse Tctex-1 protein expression by Tctex-1 protein be detected in all tissues albeit in mouse tissues largely with the mRNA expression in humans the expression in and expression in CNS and liver results E. M. K. D. Cell. 1989; Full Text PDF PubMed Scopus (95) Google Scholar, S.M. E. Dillman 3rd, J.F. Benashski S.E. 1998; PubMed Scopus Google Scholar). the of Tctex-1 mRNA expression in skeletal muscle in humans is in with the of Tctex-1 protein found in mouse skeletal muscle and The for this is not In tissues the anti-Tctex-1 antibodies a of The presence of a second was most in and and T. 1998; PubMed Scopus Google Scholar) found Tctex-1 to be by the may therefore for the of The of the in tissue remains We by the expression of Tctex-1 in mouse tissues most to poliovirus sciatic and spinal Using an affinity-purified polyclonal antibody (17Campbell K.S. Cooper S. Dessing M. Yates S. Buder A. J. Immunol. 1998; 161: 1728-1737PubMed Google Scholar) in with a we detected Tctex-1 protein in spinal cord and sciatic nerve and Tctex-1 was in spinal cord and with the This is in with the of Tctex-1 mRNA expression in CNS and other tissues that has been by and colleagues Benashski S.E. A. King S.M. J. Full Text Full Text PDF PubMed Scopus (64) Google Scholar). a of neuronal cell Tctex-1 was in the large motor neurons of the Tctex-1 was largely to small of and This was observed in the it to be along an that it be with nerve A Tctex-1 was found in sciatic nerve be that two independently derived Tctex-1 has been (17Campbell K.S. Cooper S. Dessing M. Yates S. Buder A. J. Immunol. 1998; 161: 1728-1737PubMed Google Scholar, 18King S.M. Dillman 3rd, J.F. Benashski S.E. Lye R.J. J. Full Text Full Text PDF PubMed Scopus Google identical patterns not We consider it that Tctex-1 may be in transport a by the findings of the of and independently showed the presence of Tctex-1 in axons of neurons H. Lee H. J. J. C. J. PubMed Google Scholar) and within vesicles J. PubMed Google of Tctex-1 in mouse sciatic of mouse sciatic Tctex-1 immunoreactivity is found the sciatic in patterns of of no was observed with an A the interaction of CD155 with Tctex-1, we and proteins between glutathioneS-transferase and Tctex-1 or the intracellular C-terminal of CD155α In a of the proteins, to were in a R. D.D. K. in Scholar) to to in specifically Tctex-1 not with Tctex-1 We a of Tctex-1 with an supporting a recent by and Benashski S.E. A. King S.M. J. Full Text Full Text PDF PubMed Scopus (64) Google Scholar) that Tctex-1 may form a within the dynein complex. CD155α with Tctex-1 in neuronal cells, we the experiments and Tctex-1 by in with Tctex-1 from cytoplasmic of mouse cells The to the was analyzed for the presence of Tctex-1 protein by As is in CD155α strongly with cellular Tctex-1 to with Tctex-1 the of the and membrane-bound splice variants of and with Tctex-1 in the two-hybrid we that the target for Tctex-1 binding within the cytoplasmic that splice variants have in and colleagues M. J. Full Text Full Text PDF PubMed Scopus Google Scholar) have the as a Tctex-1 motif The of CD155 cytoplasmic the which this motif We therefore a CD155α protein in which the SKCSR was to that have been of to Tctex-1 was by more than with the protein and This strongly suggests that the SKCSR is for the interaction between CD155 and We a in which we the system with the of of alkaline The cytoplasmic domain of CD155α was to the of human secreted alkaline phosphatase protein and protein were in HEK cells from which were secreted into the medium of the of expression the medium of alkaline phosphatase as by a as a for alkaline phosphatase the of the secreted proteins, we the proteins from the with an alkaline antibody and analyzed the by blot the antibody As to be than to the of the cytoplasmic domain of CD155α The secreted and were with to which proteins were Although of the proteins of protein specifically from the medium interaction was between and the of the was no observed between CD155 cytoplasmic we detected no of with an between CD155 and Tctex-1 be observed in tissue cells, we HEK 293T cells were with expression for CD155 and were to an antibody or a of monoclonal antibodies and were by and analyzed for Tctex-1 by blot As antibody the chain of Tctex-1 which is a subunit of dynein and is thought to directly with the chain S.M. E. Dillman 3rd, J.F. Benashski S.E. 1998; PubMed Scopus Google Scholar, M. J. Full Text Full Text PDF PubMed Scopus Google Scholar). mouse is not on human not Tctex-1 protein with antibodies and Tctex-1 protein be from the cell This that CD155 and Tctex-1 specifically in intact In this study we have the interaction between the cytoplasmic domain of the poliovirus receptor CD155 and Tctex-1, an that we detected in a screen. We have evidence for the of this interaction by four and in and in intact that Tctex-1 with an SKCSR motif in the juxtamembrane region of the cytoplasmic domain of CD155. We evidence of the presence of Tctex-1 protein in neurons of the spinal motor and along within the and the sciatic The interaction between CD155 and Tctex-1 to an How poliovirus motor its in the CNS, via retrograde axonal Tctex-1 was identified as a gene for in mice E. M. K. D. Cell. 1989; Full Text PDF PubMed Scopus (95) Google Scholar) and has subsequently been to be a subunit of the cytoplasmic and dynein complex S.M. Dillman 3rd, J.F. Benashski S.E. Lye R.J. J. Full Text Full Text PDF PubMed Scopus Google Scholar, M. Y. H. R. K. 1998; PubMed Scopus (26) Google Scholar). are molecular that along the driving force for a of important cellular most the minus end-directed transport of membranous vesicles and and the for and in PubMed Scopus Google Scholar). poliovirus infection has to two pathways are open for virus into the crossing the blood-brain barrier or retrograde axonal transport the neuromuscular junction evidence is for the but for the retrograde axonal transport has been as the only explanation for a phenomenon muscle may an infected to poliomyelitis (11McCloskey B.P. Lancet. 1950; 1: 659-663Abstract Scopus (18) Google Scholar, 13Gromeier M. Wimmer E. J. 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Considering that paralysis in most poliomyelitis is found in it is to that poliovirus may predominantly from retrograde axonal transport to target motor neurons by their destruction. The mechanism by which muscle a the to virus into the motor is unknown. the expression of CD155 the and its in muscle I. N. Y. Acad. Sci. PubMed Scopus Google Scholar). be muscle in to poliovirus replication or the CD155 and into the motor We propose that the virus is the nerve into an endocytic the virus remains to the the cytoplasmic of CD155 with Tctex-1, the latter retrograde transport of the via the dynein complex to the motor cell Indeed, our evidence of Tctex-1 to small within motor neurons and of membrane-bound with a This the presence of Tctex-1 the to our virus Interestingly, J. PubMed Google Scholar) found Tctex-1 to be in small vesicles axon of of Although it has not been directly the that Tctex-1 is motor axon and colleagues T. 1998; PubMed Scopus Google Scholar) found the protein to be in the an a large neuromuscular with our evidence and that of H. Lee H. J. J. C. J. PubMed Google Scholar) of Tctex-1 within the sciatic it is to that Tctex-1 may a function in retrograde transport from the motor axon to the neuronal cell body. The recent findings of and colleagues H. Lee H. J. J. C. J. PubMed Google Scholar) support to this This showed that retrograde axonal transport of and within the sciatic nerve of is by of with the dynein motor complex via binding of Tctex-1 H. Lee H. J. J. C. J. PubMed Google Scholar). like nerve to remain to the dynein motor as a complex for the of transport from the of the the neuronal cell body. This mechanism to our model of poliovirus retrograde axonal transport. and colleagues J. 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Mueller et al. (Fri,) conducted a other in Poliovirus pathogenesis. CD155 cytoplasmic domain was evaluated on Protein-protein interaction between CD155 and Tctex-1. The cytoplasmic domain of the poliovirus receptor CD155 associates strongly and specifically with Tctex-1, a light chain of the dynein motor complex, mapping to a SKCSR motif.