1538 Biol. Pharm. Bull. 29(8) 1538—1541 (2006) Vol. 29, No. 8 Current Topics Lipid Dynamics and Pathobiology in Membrane Lipid Rafts

Virus Infection and Lipid Rafts

Takashi SUZUKI* and Yasuo SUZUKI COE Program in the 21st Century, Department of Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka; 52–1 Yada, Suruga-ku, Shizuoka 422–8526, Japan. Received February 1, 2006

Virus entry, assembly, and budding are important processes in the replication cycle of a virus. are dependent on host living cells for their replication. Viruses use the proliferative mechanism of host cells for repli- cation of viral components. Lipid rafts, specific membrane microdomains play a critical role in virus replication because localizing and concentrating viral components in the microdomains for entry, assembly, and budding of various types of virus. In this review, we describe the involvement of membrane lipid rafts in the virus replication cycle with our current findings for understanding the role of membrane lipid rafts in virus infection. Key words virus; infection; lipid; rafts

1. INTRODUCTION terovirus16—18) (belonging to the Picornaviridae family), species C human adenovirus (HAdV)19) (belong to the Aden- Lipid rafts, specific membrane microdomains enriched in oviridae family), and rhinovirus20) (belonging to the Picor- cholesterol and (glyco)sphingolipids, are known to be in- naviridae family). volved in the regulation of various biological phenomena, in- The entry process of SV40 is mediated by caveolae which cluding membrane transport and signal transduction path- transport viral particles to the ER. Infection of SV40 to the ways.1—5) The involvement of membrane lipid rafts in virus target cells utilizes major histocompatibility complex class I entry, assembly, and budding has been demonstrated by the (MHC-I), which is not localized in lipid rafts but induces localization of viral structural proteins and the effects of raft- association of SV40 with caveolae,6—10) or GM1 ganglio- disrupting agents in the replication processes of several side,11,12) which is located in lipid rafts, as receptors. viruses. However, the role of membrane lipid rafts in the Group A infect epithelial cells via a complex virus replication cycle remains unknown. Viruses first attach of several cell molecules, including gangliosdes, glycopro- to specific receptors on the surfaces of target cells and enter teins, Hsc70 protein, and a Vb 3 integrin, that are present in the cells. Viruses generally enter the cells by endocytosis or penetration of viral particles directly into the cytoplasm and release viral genes by fusion of the or destruc- tion of the viral . The majority of DNA viruses except poxviruses undergo transcription and replication inside the nucleus, whereas transcription and replication of most RNA viruses except influenza virus occur in the cytoplasm (Fig. 1). The newly synthesized viral components are transported to organelles or the plasma membrane for assembly and/or budding of the virus. Viruses are classified two types, en- veloped and nonenveloped viruses, on the basis of outer structures. Enveloped virus particles are released from the plasma membrane, nuclear membrane, Golgi apparatus, or endoplasmic reticulum (ER) by budding. Nonenveloped viruses are generally released by the burst of cells after as- sembly of viral components in the cytoplasm (Fig. 2). In the this review, we discuss recent understandings on the function of lipid rafts in the replication of viruses.

2. ROLE OF LIPID RAFTS IN VIRUS ENTRY

The involvement of membrane lipid rafts in entry of nonenveloped viruses has been demonstrated by simian virus 40 (SV40)6—12) (belonging to the Papovaviridae family), ro- tavirus13,14) (belonging to the Reoviridae family), echovirus type 115) (belonging to the Picornaviridae family), en- Fig. 1. Entry of Enveloped and Nonenveloped Viruses into the Host Cells

∗ To whom correspondence should be addressed. e-mail: [email protected] © 2006 Pharmaceutical Society of Japan August 2006 1539

The majority of enveloped viruses lead to conformational change of viral structural or transmembrane proteins that in- duce fusion of viral and plasma membranes and release of viral genes after attachment of the virus to receptors and/or endocytosis. Influenza viruses bind to glycoconjugates containing sialic acid in the cell membrane lipid rafts via hemagglutinin (HA)33,34) and enter cells via multiple pathways, with both clathrin-mediated and clathrin- and caveolin-independent en- docytosis.21—23) Subsequently, the viruses are transported to late endosomes, where the low-pH condition induces mem- brane fusion between the viral and endosomal membranes for releasing the viral ribonucleoprotein complexes. HIV-1 initiates infection by binding to CD4 via the viral surface glycoprotein gp 120. This binding induces a confor- mational change in gp 120 for interaction with the second cell-surface receptors (coreceptors) CXCR4 or CCR5 and a subsequent conformational change in the transmembrane glycoprotein gp 41 for membrane fusion.35—37) Both CD4 and CCR5 but not CXCR4 are known to be associated with membrane lipid rafts.38,39) Additionally, glycosphingolipids of target cells, including globotriaosyl ceramide (Gb3), GM3 ganglioside, and galactosylceramide, are involved in func- tions of the viral glycoproteins in the HIV-1 entry Fig. 2 Assembly and Budding of Enveloped and Nonenveloped Viruses 40—42) (A) The genes of nonenveloped DNA viruses; (B) the genes of influenza virus or en- process. veloped DNA viruses; (C) the genes of enveloped RNA viruses. Ebola virus and Marburg virus appear to enter cells via specific cell surface receptors; folate receptor a (FRa) has been identified as a coreceptor for virus entry, but other re- membrane lipid rafts.13,14) ceptors remain unknown. The effects of raft-disrupting

Echovirus type 1 initiates infection by binding to a 2b 1-in- agents on Ebola virus infection indicate a critical role of tegrin, which induces activation of caveola endocytosis. The membrane lipid rafts in filovirus entry. involvement of membrane lipid rafts in echovirus type 1 in- EBV infects human B lymphocytes via human comple- fection has been suggested findings that echovirus type 1 in- ment receptor type 2 (CR2; CD21), which forms part of fection is inhibited by treatment with methyl-b-cyclodextrin complex with CD19 and CD81 in lipid rafts. The CD19/ and by the expression of a dominant negative caveolin.15) CD21/CD81 complex functions to prolong B cell antigen re- Some species of HAdV generally internalize by clathrin- ceptor signaling from lipid rafts and leads to palmitoylation coated pits after binding with the adenoviruses receptor.21) of CD81.29,30) This internalization is induced by interaction of the RGD Binding of HSV to host cells and entry of HSV into host motif of the virus with a Vb 3, a Vb 5, a Mb 2, and a 5b 1 inte- cells are mediated by a complex process involving the essen- grins, which induce clathrin-coated pit endocytosis of HAdV. tial viral glycoproteins B (gB), gD, gH, and gL and multiple While, a clathrin-independent, lipid rafts and/or caveola en- celluar receptor molecules, including the tumor necrosis fac- docytosis pathway involves in the entry of HAdV to plasmo- tor receptor family members nectin-1 and nectin-2, her- cytic cells.19) pesvirus entry mediator, heparan sulfate proteoglycans, and Rhinoviruses infect human epithelial cells via ceramide- two members of it the mmunoglobulin superfamily.43—45) enriched membrane platforms produced by acid sphin- HSV entry is inhibited by cholesterol-sequestering drugs gomyelinase.20) Rhinoviruses induce activation and transloca- such as methyl-b-cyclodextrin and nystatin. Moreover, HSV tion of acid sphingomyelinase onto the extracellular leaflet of gB has been detected in lipid rafts after virus attachment and the cell membrane. The activity of acid sphingomyelinase re- during entry.31,32) sults in a reorganization of small membrane rafts and the for- Semliki Forest virus and Sindbis virus (belonging to the mation of ceramide-enriched membrane platforms. The sig- Togaviridae family) infect farget cells by receptor-mediated nificance of ceramide-enriched membrane platforms for rhi- endocytosis and subsequent low-pH triggered fusion from noviral entry has been demonstrated by genetic deficiency within acidic endosomes. Cholesterol is required for and pharmacological inhibitors of acid sphingomyelinase. enrty46—48); however, the viruses may not require the pres- The involvement of membrane lipid rafts in entry of ence of lipid rafts for fusion with target membranes.49) enveloped viruses has been demonstrated by influenza virus21—23) (belonging to the family), 3. ROLE OF LIPID RAFTS IN VIRUS ASSEMBLY human immunodeficiency virus (HIV)24—26) (belonging to AND/OR BUDDING the Retroviridae family), Ebola virus and Marburg virus27,28) (belonging to the family), Epstein-Barr virus The involvement of membrane lipid rafts in the intracellu- (EBV)29,30) and virus 1 (HSV)31,32) (belonging lar assembly of a nonenveloped virus is demonstrated on to the family). atypical targeting of .50,51) 1540 Vol. 29, No. 8

A rotavirus follows an atypical pathway to the cell mem- melanoma, which lacks the ability to synthesize major gly- brane by the way of the Golgi apparatus. A direct interaction cosphingolipids, including gangliosides, did not show an ob- of VP4, which is the most peripheral protein of the triple-lay- vious disparity in comparison with that in the parent cells.34) ered structure of a rotavirus, with lipid rafts promotes assem- It seems that gangliosides are not essential for influenza virus bly and atypical targeting of the rotavirus in intestinal cells. infection. M1 plays a critical role for the viral assembly and There is much less information of the role of lipid rafts about budding. M1 is not associated with lipid rafts but is essential other nonenveloped virus assembly. for the formation of influenza virus particles since their for- Membrane lipid rafts also play a critical role in assembly mation can not be incorporated the absence of M1 but not and budding of several enveloped viruses. virus (be- any other viral proteins.68,69) M1 is incorporated into lipid longing to the family) structural proteins rafts by interaction with HA.70) are enriched in membrane lipid rafts, which seem to provide a platform for the viral assembly and budding.52) Envelope 4. CONCLUSION AND PERSPECTIVES glycoprotein (G protein) of vesicular stomatitis virus (be- longing to the family) is also organized into As described above, many recent studies suggest that lipid membrane lipid raft microdomains for assembly of internal rafts play a critical role in the process of viral infection. In virion components.53) most cases, the involvement of membrane lipid rafts in virus Ebola and Marburg viruses are released from raft-associ- entry, assembly, and budding are demonstrated on the local- ated regions. Ebola virus proteins are compartmentalized in ization of viral structural proteins and the effects of raft-dis- lipid rafts during viral assembly. The oligomerization of the rupting agents in the replication processes of several viruses. viral matrix protein VP40, which plays a critical role in Why are membrane lipid rafts used for entry, assembly, and Ebola virus assembly and budding, is regulated in the plasma budding of several viruses? What is the role of lipid rafts in membrane by association with lipid rafts.27,54) the virus replication cycle? How does each in- Paramyxoviruses such as respiratory syncytial virus teract with lipid raft components? Several new approaches (RSV),55—57) Sendai virus,58) and measles virus (MV)52,59) use will be needed to elucidate the function of membrane lipid lipid rafts for assembly and budding. RSV polymerase com- rafts. An understanding of the molecular organization of plex associates with lipid rafts in virus-infected cells. Addi- lipid rafts and the function of lipid rafts in the viral replica- tionally, RSV assembly occurs within lipid rafts regions that tion cycle might contribute to the elucidation of cell mem- are enriched in caveolin-1 and alters the cellular distribution brane function and to the development of new antivirus of tyrosine -hosphorylated caveolin-1. chemotherapy. Additional studies on the role of membrane In assembly of Sendai virus, the matrix protein (M pro- lipid rafts in the viral replication cycle should be carried out tein) interacts with cytoplasmic tails of hemagglutinin-neu- in the future. raminidase (HN) and fusion (F) proteins and with the trans- membrane domain of F protein. M protein, which alone is REFERENCES preferentially associated with nonraft membranes, colocal- izes with HN and F glycoproteins in lipid rafts for assembly. 1) Keller P., Simons K., J. Cell. Biol., 140, 1357—1367 (1998). 2) Sheets E. D., Holowka D., Baird B., Curr. Opin. Chem. Biol., 3, 95— Membrane lipid rafts provide a platform for assembly and 99 (1999). 60,61) budding of HIV-1. HIV-1 assembly and budding is in- 3) Roy S., Luetterforst R., Harding A., Apolloni A., Etheridge M., Stang duced by modification of HIV-1 Gag protein (Pr 55Gag) with E., Rolls B., Hancock J. F., Parton R. G., Nat. Cell Biol., 1, 98—105 myristic acid. Gag protein associates with the plasma mem- (1999). 4) Laux T., Fukami K., Thelen M., Golub T., Frey D., Caroni P., J. Cell brane, leading to the formation of HIV-1 particles. The viral Biol., 149, 1455—1472 (2000). surface glycoprotein complex (gp120 and ) is incorpo- 5) Prior I. A., Harding A., Yan J., Sluimer J., Parton R. G., Hancock J. F., rated into the envelope by interactions of Gag with the cyto- Nat. Cell Biol., 3, 368—375 (2001). plasmic tail of gp 41. Myristoylation of Gag protein pro- 6) Stang E. J., Kartenbeck J., Parton R. G., Mol. Biol. Cell, 8, 47—57 motes Gag–Gag interactions (Gag multimerization). Choles- (1997). 7) Anderson H. A., Chen. Y., Norkin L. C., J. Gen. Virol., 79, 1469— terol depletion or treatment of unsaturated fatty acids inhibits 1477 (1998). Gag-driven particle assembly. The Gag–Gag interaction do- 8) Parton R. G., Lindsay M., Immunol. Rev., 168, 23—31 (1999). main (NC domain) located in the N terminus of the viral nu- 9) Norkin L. C., Anderson H. A., Wolfrom S. A., Oppenheim A., J. cleocapsid is important for Gag multimerization; however, Virol., 76, 5156—5166 (2002). this process dose not seem to be necessary for association of 10) Pelkmans L., Kartenbeck J., Helenius A., Nat. Cell Biol., 3, 473—483 62) (2001). Gag with membrane lipid rafts. 11) Tsai B., Gilbert J. M., Stehle T., Lencer W., Benjamin T. L., Rapoport Influenza virus particles consist of eight viral ribonucleo- T. A., EMBO J., 22, 4346—4355 (2003). protein with an envelope that includes two spike gly- 12) Gilbert J., Dahl J., Riney C., You J., Cui C., Holmes R., Lencer W., coproteins, HA and neuraminidase (NA), and ion-channel Benjamin T., J. Virol., 79, 615—618 (2005). protein M2 on the outer surface and matrix protein (M1) on 13) Guerrero C. A., Bouyssounade D., Zarate S., Isa P., Lopez T., Espinosa 63) R., Romero P., Mendez E., Lopez S., Arias C. F., J. Virol., 76, 4096— the inner surface. The two spike glycoproteins and M2 4102 (2002). possess apical sorting and targeting signals and utilize mem- 14) Arias C. F., Isa P., Guerrero C. A., Mendez E., Zarate S., Lopez T., Es- brane lipid rafts for apical sorting. HA and NA concentrate pinosa R., Romero P., Lopez S., Arch. Med. Res., 33, 356—361 in lipid rafts via their individual of transmembrane domains, (2002). the cytoplasmic tails, and via palmitoylation in the case of 15) Marjomaki V., Pietiaimen V., Matilainen H., Upla P., Ivaska J., Nissi- 64—67) nen L., Reunanen H., Huttunen P., Hyypia T., Heino J., J. Virol., 76, HA. Replication of avian and human influenza A 1856—1865 (2002). viruses in the GM-95 mutant cell line of mouse B16 16) Bergelson J. M., Chan M., Solomon K. R., St John N. F., Lin H., Fin- August 2006 1541

berg R. W., Proc. Natl. Acad. Sci. U.S.A., 91, 6245—6249 (1994). Tamalet C., Fantini J., J. Biol. Chem., 273, 7967—7971 (1998). 17) Karnauchow T. M., Tolson D. L., Harrison B. A., Altman E., Lublin D. 42) Fantini J., Cook D. G., Nathanson N., Spitalnik S. L., Gonzalez- M., Dimock K., J. Virol., 70, 5143—5152 (1996). Scarano F., Proc. Natl. Acad. Sci. U.S.A., 90, 2700—2704 (1993). 18) Stuart A. D., Eustace H. E., Mckee T. A., Brown T. D., J. Virol., 76, 43) Geraghty R. J., Krummenacher C., Cohen G. H., Eisenberg R. J., 9307—9322 (2002). Spear P. G., Science, 280, 1618—1620 (1998). 19) Colin M., Mailly L., Rogee S., D’Halluin J.-C., Mol. Ther., 11, 224— 44) Montgomery R. I., Warner M. S., Lum B. J., Spear P. G., Cell, 87, 236 (2005). 427—436 (1996). 20) Grasseme H., Riehle A., Wilker B., Gulbins E., J. Biol. Chem., 280, 45) Bender F. C., Whitbeck J. C., Lou H., Cohen G. H., Eisenberg R. J., J. 26256—26262 (2005). Virol., 79, 11588—11597 (2005). 21) Sieczkarski S. B., Whittaker G. R., J. Virol., 76, 10455—10464 46) Kielean M. C., Helenius A., J. Virol., 52, 281—283 (1984). (2002). 47) Phalen T., Kielian M., J. Cell Biol., 112, 615—623 (1991). 22) Lakadamyali M., Rust M. J., Zhuang X., Microbes Infect., 6, 929—936 48) Lu Y. E., Cassese E. T., Kielian M., J. Virol., 73, 4272—4278 (1999). (2004). 49) Waarts B. L., Bittman R., Wilschut J., J. Biol. Chem., 277, 38141— 23) Smith A. E., Helenius A., Science, 304, 237—242 (2004). 38147 (2002). 24) Manes S., del Real G., Lacalle R. A., Lucas P., Gomez-Mouton C., 50) Sapin C., Colard O., Delmas O., Tessier C., Breton M., Enouf V., Sanchez-Palomino S., Delgado R., Alcami J., Mira E., Martinez-A. C., Chwetzoff S., Ouanich J., Cohen J., Wolf C., Trugnan G., J. Virol., 76, EMBO Rep., 1, 190—196 (2000). 4591—4602 (2002). 25) Campbell S. M., Crowe S. M., Mak J., J. Clin. Virol., 22, 217—227 51) Delmas O., Durand-Schneider A. M., Cohen J., Colard O., Trugnan G., (2001). J. Virol., 78, 10987—10994 (2004). 26) Liao Z., Graham D. R., Hildreth J. E., AIDS Res. Hum. , 52) Manie S. N., Debreyne S., Vincent S., Gerlier D., J. Virol., 74, 305— 19, 675—687 (2003). 311 (2000). 27) Bavari S., Bosio C. M., Wiegand E., Ruthel G., Will A. B., Geisbert T. 53) Brown E. L., Lyles D. S., Virology, 310, 343—358 (2003). W., Hevey M., Schmaljohn C., Schmaljohn A., Aman M. J., J. Exp. 54) Panchal R. G., Ruthel G., Kenny T. A., Kallstrom G. H., Lane D., Med., 195, 593—602 (2002). Badie S. S., Li L., Bavari S., Aman M. J., Proc. Natl. Acad. Sci. 28) Aman M. J., Bosio C. M., Panchal R. G., Burnett J. C, Schmaljohn A., U.S.A., 100, 15936—15941 (2003). Bavari S., Microbes Infect., 5, 639—649 (2003). 55) Brown G., Rixon H. W., Sugrue R. J., J. Gen. Virol., 83, 1841—1850 29) Fingeroth J. D., Weis J. J., Tedder T. F., Strominger J. L., Biro P. A., (2002). Fearon D. T., Proc. Natl. Acad. Sci. U.S.A., 81, 4510—4514 (1984). 56) Marty A., Meanger J., Mills J., Shields B., Ghildyal R., Arch. Virol., 30) Cherukuri A., Carter R. H., Brooks S., Bornmann W., Finn R., Dowd 149, 199—210 (2004). C. S., Pierce S. K., J. Biol. Chem., 279, 31973—31982 (2004). 57) McDonald T. P., Pitt A. R., Brown G., Rixon H. W., Sugrue R. J., Vi- 31) Lee G. E., Church G. A., Wilson D. W., J. Virol., 77, 2038—2045 rology, 330, 147—157 (2004). (2003). 58) Ali A., Nayak D. P., Virology, 276, 289—303 (2000). 32) Bender F. C., Whitbeck J. C., Ponce de Leon M., Lou H., Eisenberg R. 59) Vincent S., Gerlier D., Manie S. N., J. Virol., 74, 9911—9915 (2000). J., Cohen G. H., J. Virol., 77, 9542—9552 (2003). 60) Ono A., Freed E. O., Proc. Natl. Acad. Sci. U.S.A., 98, 13925—13930 33) Suzuki Y., Ito T., Suzuki T., Holland R. E., Chambers T. M., Kiso M., (2001). Ishida H., Kawaoka Y., J. Virol., 74, 11825—11831 (2000). 61) Lindwasser O. W., Resh M. D., Proc. Natl. Acad. Sci. U.S.A., 99, 34) Matrosovich M., Suzuki T., Hirabayashi Y., Garten W., Webster R. G., 13037—13042 (2002). Klenk H.-D., Glycoconj. J., 23, 107—113 (2006). 62) Ono A., Waheed A. A., Joshi A., Freed E. O., J. Virol., 79, 14131— 35) Deng H., Liu R., Ellmeier W., Choe S., Unutmaz D., Burkhart M., Di 14140 (2005). Marzio P., Marmon S., Sutton R. E., Hill C. M., Davis C. B., Peiper S. 63) Lamb R. A., Krug R. M., “Fields Virology,” 3rd ed., ed. by Fields B. C., Schall T. J., Littman D. R., Landau N. R., Nature (London), 381, N., Knipe D. M., Howley P. M., Lippincott-Raven Publishers, Piladel- 661—666 (1996). phia, 1996, pp. 1353—1395. 36) Dragic T., Litwin V., Allaway G. P., Martin S. R., Huang Y., Na- 64) Barman S., Nayak D. P., J. Virol., 74, 6538—6545 (2000). gashima K. A., Cayanan C., Maddon P. J., Koup R. A., Moore J. P., 65) Scheiffele P., Roth M. G., Simons K., EMBO J., 16, 5501—5508 Paxton W. A., Nature (London), 381, 667—673 (1996). (1997). 37) Briggs D. R., Tuttle D. L., Sleasman J. W., Goodenow M. M., AIDS, 66) Zhang J., Pekosz A., Lamb R. A., J. Virol., 74, 4634—4644 (2000). 14, 2937—2939 (2000). 67) Melkonian K. A., Ostermeyer A. G., Chen J. Z., Roth M. G., Brown D. 38) Janes P. W., Ley S. C., Magee A. I., J. Cell Biol., 147, 447—461 A., J. Biol. Chem., 274, 3910—3917 (1999). (1999). 68) Mena I., Vivo A., Perez E., Portela A., J. Virol., 70, 5016—5024 39) Kozak S. L., Heard J. M., Kabat D., J. Virol., 76, 1802—1815 (2002). (1996). 40) Puri A., Hug P., Jernigan K., Barchi J., Kim H. Y., Hamilton J., Wiels 69) Gomez-Puertas P., Albo C., Perez-Pastrana E., Vivo A., Portela A., J. J., Murray G. J., Brady R. O., Blumenthal R., Proc. Natl. Acad. Sci. Virol., 74, 11538—11547 (2000). U.S.A., 95, 14435—14440 (1998). 70) Ali A., Avalos R. T., Ponimaskin E., Nayak D. P., J. Virol., 74, 8709— 41) Hammache D., Pieroni G., Yahi N., Delezay O., Koch N., Lafont H., 8719 (2000).