{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T06:18:32Z","timestamp":1791181112776,"version":"4.1.0"},"reference-count":52,"publisher":"National Academy of Sciences","issue":"8","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1999,4,13]]},"abstract":"<jats:p>Retroviral entry into cells depends on envelope glycoproteins, whereby receptor binding to the surface-exposed subunit triggers membrane fusion by the transmembrane protein (TM) subunit. We determined the crystal structure at 2.5-\u212b resolution of the ectodomain of gp21, the TM from human T cell leukemia virus type 1. The gp21 fragment was crystallized as a maltose-binding protein chimera, and the maltose-binding protein domain was used to solve the initial phases by the method of molecular replacement. The structure of gp21 comprises an N-terminal trimeric coiled coil, an adjacent disulfide-bonded loop that stabilizes a chain reversal, and a C-terminal sequence structurally distinct from HIV type 1\/simian immunodeficiency virus gp41 that packs against the coil in an extended antiparallel fashion. Comparison of the gp21 structure with the structures of other retroviral TMs contrasts the conserved nature of the coiled coil-forming region and adjacent disulfide-bonded loop with the variable nature of the C-terminal ectodomain segment. The structure points to these features having evolved to enable the dual roles of retroviral TMs: conserved fusion function and an ability to anchor diverse surface-exposed subunit structures to the virion envelope and infected cell surface. The structure of gp21 implies that the N-terminal fusion peptide is in close proximity to the C-terminal transmembrane domain and likely represents a postfusion conformation.<\/jats:p>","DOI":"10.1073\/pnas.96.8.4319","type":"journal-article","created":{"date-parts":[[2002,7,26]],"date-time":"2002-07-26T10:39:15Z","timestamp":1027679955000},"page":"4319-4324","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":181,"title":["Crystal structure of human T cell leukemia virus type 1 gp21 ectodomain crystallized as a maltose-binding protein chimera reveals structural evolution of retroviral transmembrane proteins"],"prefix":"10.1073","volume":"96","author":[{"given":"Bostjan","family":"Kobe","sequence":"first","affiliation":[{"name":"St. Vincent\u2019s Institute of Medical Research, 41 Victoria Parade, Fitzroy, Victoria 3065, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rob J.","family":"Center","sequence":"additional","affiliation":[{"name":"St. Vincent\u2019s Institute of Medical Research, 41 Victoria Parade, Fitzroy, Victoria 3065, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bruce E.","family":"Kemp","sequence":"additional","affiliation":[{"name":"St. Vincent\u2019s Institute of Medical Research, 41 Victoria Parade, Fitzroy, Victoria 3065, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pantelis","family":"Poumbourios","sequence":"additional","affiliation":[{"name":"St. Vincent\u2019s Institute of Medical Research, 41 Victoria Parade, Fitzroy, Victoria 3065, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[1999,4,13]]},"reference":[{"key":"e_1_3_4_1_2","doi-asserted-by":"crossref","first-page":"7415","DOI":"10.1073\/pnas.77.12.7415","volume":"77","author":"Poiesz B J","year":"1980","unstructured":"B J Poiesz, F W Ruscetti, A F Gazdar, P A Bunn, J D Minna, R C Gallo Proc Natl Acad Sci USA 77, 7415\u20137419 (1980).","journal-title":"Proc Natl Acad Sci USA"},{"key":"e_1_3_4_2_2","doi-asserted-by":"crossref","first-page":"1031","DOI":"10.1016\/S0140-6736(86)91298-5","volume":"1","author":"Osame M","year":"1986","unstructured":"M Osame, K Usuku, S Izumo, N Ijishi, H Amitani, A Igata, M Matsumoto, M Tara Lancet 1, 1031\u20131032 (1986).","journal-title":"Lancet"},{"key":"e_1_3_4_3_2","doi-asserted-by":"crossref","first-page":"905","DOI":"10.1128\/jcm.30.4.905-910.1992","volume":"30","author":"Fan N","year":"1992","unstructured":"N Fan, J Gavalchin, B Paul, K Wells, M J Lane, B Poiesz J Clin Microbiol 30, 905\u2013910 (1992).","journal-title":"J Clin Microbiol"},{"key":"e_1_3_4_4_2","doi-asserted-by":"crossref","first-page":"478","DOI":"10.1046\/j.1537-2995.1994.34694295061.x","volume":"34","author":"Donegan E","year":"1994","unstructured":"E Donegan, H Lee, E A Operskalski, G M Shaw, S H Kleinman, M P Busch, C E Stevens, E R Schiff, M J Nowicki, C G Hollingsworth, et al. Transfusion 34, 478\u2013483 (1994).","journal-title":"Transfusion"},{"key":"e_1_3_4_5_2","doi-asserted-by":"crossref","first-page":"906","DOI":"10.1128\/jvi.66.2.906-913.1992","volume":"66","author":"Pique C","year":"1992","unstructured":"C Pique, D Pham, T Tursz, M-C Dokh\u00e9lar J Virol 66, 906\u2013913 (1992).","journal-title":"J Virol"},{"key":"e_1_3_4_6_2","doi-asserted-by":"crossref","first-page":"1455","DOI":"10.1083\/jcb.139.6.1455","volume":"139","author":"Hernandez L D","year":"1997","unstructured":"L D Hernandez, R J Peters, S E Delos, J A T Young, D A Agard, J M White J Cell Biol 139, 1455\u20131464 (1997).","journal-title":"J Cell Biol"},{"key":"e_1_3_4_7_2","doi-asserted-by":"crossref","first-page":"431","DOI":"10.1089\/aid.1989.5.431","volume":"5","author":"Gallaher W R","year":"1989","unstructured":"W R Gallaher, J M Ball, R F Garry, M C Griffin, R C Montelaro AIDS Res Hum Retroviruses 5, 431\u2013440 (1989).","journal-title":"AIDS Res Hum Retroviruses"},{"key":"e_1_3_4_8_2","doi-asserted-by":"crossref","first-page":"465","DOI":"10.1038\/nsb0596-465","volume":"3","author":"Fass D","year":"1996","unstructured":"D Fass, S C Harrison, P S Kim Nat Struct Biol 3, 465\u2013469 (1996).","journal-title":"Nat Struct Biol"},{"key":"e_1_3_4_9_2","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1016\/S0092-8674(00)80205-6","volume":"89","author":"Chan D C","year":"1997","unstructured":"D C Chan, D Fass, J M Berger, P S Kim Cell 89, 263\u2013273 (1997).","journal-title":"Cell"},{"key":"e_1_3_4_10_2","doi-asserted-by":"crossref","first-page":"426","DOI":"10.1038\/387426a0","volume":"387","author":"Weissenhorn W","year":"1997","unstructured":"W Weissenhorn, A Dessen, S C Harrison, J J Skehel, D C Wiley Nature (London) 387, 426\u2013430 (1997).","journal-title":"Nature (London)"},{"key":"e_1_3_4_11_2","doi-asserted-by":"crossref","first-page":"12303","DOI":"10.1073\/pnas.94.23.12303","volume":"94","author":"Tan K","year":"1997","unstructured":"K Tan, J-H Liu, J-H Wang, S Shen, M Lu Proc Natl Acad Sci USA 94, 12303\u201312308 (1997).","journal-title":"Proc Natl Acad Sci USA"},{"key":"e_1_3_4_12_2","doi-asserted-by":"crossref","first-page":"9134","DOI":"10.1073\/pnas.95.16.9134","volume":"95","author":"Malashkevich V N","year":"1998","unstructured":"V N Malashkevich, D C Chan, C T Chutkowski, P S Kim Proc Natl Acad Sci USA 95, 9134\u20139139 (1998).","journal-title":"Proc Natl Acad Sci USA"},{"key":"e_1_3_4_13_2","doi-asserted-by":"crossref","first-page":"4572","DOI":"10.1093\/emboj\/17.16.4572","volume":"17","author":"Caffrey M","year":"1998","unstructured":"M Caffrey, M Cai, J Kaufman, S J Stahl, P T Wingfield, D G Covell, A M Gronenborn, G M Clore EMBO J 17, 4572\u20134584 (1998).","journal-title":"EMBO J"},{"key":"e_1_3_4_14_2","doi-asserted-by":"crossref","first-page":"6349","DOI":"10.1128\/jvi.65.11.6349-6352.1991","volume":"65","author":"Syu W-J","year":"1991","unstructured":"W-J Syu, W-R Lee, B Du, Q-C Yu, M Essex, T-H Lee J Virol 65, 6349\u20136352 (1991).","journal-title":"J Virol"},{"key":"e_1_3_4_15_2","doi-asserted-by":"crossref","first-page":"5225","DOI":"10.1073\/pnas.85.14.5225","volume":"85","author":"Klasse P J","year":"1988","unstructured":"P J Klasse, R Pipkorn, J Blomberg Proc Natl Acad Sci USA 85, 5225\u20135229 (1988).","journal-title":"Proc Natl Acad Sci USA"},{"key":"e_1_3_4_16_2","doi-asserted-by":"crossref","first-page":"6159","DOI":"10.1073\/pnas.83.16.6159","volume":"83","author":"Wang J J","year":"1986","unstructured":"J J Wang, S Steel, R Wisniewolski, C Y Wang Proc Natl Acad Sci USA 83, 6159\u20136163 (1986).","journal-title":"Proc Natl Acad Sci USA"},{"key":"e_1_3_4_17_2","doi-asserted-by":"crossref","first-page":"1571","DOI":"10.1089\/aid.1992.8.1571","volume":"8","author":"Schulz T F","year":"1992","unstructured":"T F Schulz, B A Jameson, L Lopalco, A G Siccardi, R A Weiss, J P Moore AIDS Res Hum Retroviruses 8, 1571\u20131580 (1992).","journal-title":"AIDS Res Hum Retroviruses"},{"key":"e_1_3_4_18_2","doi-asserted-by":"crossref","first-page":"1612","DOI":"10.1002\/pro.5560070715","volume":"7","author":"Center R J","year":"1998","unstructured":"R J Center, B Kobe, K A Wilson, T Teh, G J Howlett, B E Kemp, P Poumbourios Protein Sci 7, 1612\u20131619 (1998).","journal-title":"Protein Sci"},{"key":"e_1_3_4_19_2","first-page":"56","volume-title":"Proceedings of the CCP4 Study Weekend: Data Collection and Processing","author":"Otwinowski Z","year":"1993","unstructured":"Z Otwinowski Proceedings of the CCP4 Study Weekend: Data Collection and Processing, eds L Sawyer, N Isaacs, S Bailey (Science and Engineering Research Council, Daresbury Laboratory, Warrington, U.K.), pp. 56\u201362 (1993)."},{"key":"e_1_3_4_20_2","doi-asserted-by":"crossref","first-page":"997","DOI":"10.1016\/S0969-2126(97)00253-0","volume":"5","author":"Quiocho F A","year":"1997","unstructured":"F A Quiocho, J C Spurlino, L E Rodseth Structure (London) 5, 997\u20131015 (1997).","journal-title":"Structure (London)"},{"key":"e_1_3_4_21_2","doi-asserted-by":"crossref","first-page":"740","DOI":"10.1107\/S0907444995001284","volume":"51","author":"DeLano W L","year":"1995","unstructured":"W L DeLano, A T Br\u00fcnger Acta Crystallogr D 51, 740\u2013748 (1995).","journal-title":"Acta Crystallogr D"},{"key":"e_1_3_4_22_2","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1107\/S0108767390010224","volume":"47","author":"Jones T A","year":"1991","unstructured":"T A Jones, J-Y Zou, S W Cowan, M Kjeldgaard Acta Crystallogr A 47, 110\u2013119 (1991).","journal-title":"Acta Crystallogr A"},{"key":"e_1_3_4_23_2","doi-asserted-by":"crossref","first-page":"472","DOI":"10.1038\/355472a0","volume":"355","author":"Br\u00fcnger A T","year":"1992","unstructured":"A T Br\u00fcnger Nature (London) 355, 472\u2013475 (1992).","journal-title":"Nature (London)"},{"key":"e_1_3_4_24_2","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1107\/S0907444992008886","volume":"49","author":"Lamzin V S","year":"1993","unstructured":"V S Lamzin, K S Wilson Acta Crystallogr D 49, 129\u2013147 (1993).","journal-title":"Acta Crystallogr D"},{"key":"e_1_3_4_25_2","doi-asserted-by":"crossref","first-page":"283","DOI":"10.1107\/S0021889892009944","volume":"26","author":"Laskowski R A","year":"1993","unstructured":"R A Laskowski, M W MacArthur, D S Moss, J M Thornton J Appl Crystallogr 26, 283\u2013291 (1993).","journal-title":"J Appl Crystallogr"},{"key":"e_1_3_4_26_2","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1038\/371037a0","volume":"371","author":"Bullough P A","year":"1994","unstructured":"P A Bullough, F M Hughson, J J Skehel, D C Wiley Nature (London) 371, 37\u201343 (1994).","journal-title":"Nature (London)"},{"key":"e_1_3_4_27_2","doi-asserted-by":"crossref","first-page":"1317","DOI":"10.1128\/jvi.71.2.1317-1333.1997","volume":"71","author":"Mahieux R","year":"1997","unstructured":"R Mahieux, F Ibrahim, P Mauclere, V Herve, P Michel, F Tekaia, C Chappey, B Garin, E Van Der Ryst, B Guillemaine, et al. J Virol 71, 1317\u20131333 (1997).","journal-title":"J Virol"},{"key":"e_1_3_4_28_2","doi-asserted-by":"crossref","first-page":"7180","DOI":"10.1128\/jvi.71.10.7180-7186.1997","volume":"71","author":"Rosenberg A R","year":"1997","unstructured":"A R Rosenberg, L Delamarre, C Pique, D Pham, M-C Dokh\u00e9lar J Virol 71, 7180\u20137186 (1997).","journal-title":"J Virol"},{"key":"e_1_3_4_29_2","doi-asserted-by":"crossref","first-page":"1075","DOI":"10.1038\/nsb1295-1075","volume":"2","author":"Lu M","year":"1995","unstructured":"M Lu, S C Blacklow, P S Kim Nat Struct Biol 2, 1075\u20131082 (1995).","journal-title":"Nat Struct Biol"},{"key":"e_1_3_4_30_2","doi-asserted-by":"crossref","first-page":"14955","DOI":"10.1021\/bi00046a001","volume":"34","author":"Blacklow S C","year":"1995","unstructured":"S C Blacklow, M Lu, P S Kim Biochemistry 34, 14955\u201314962 (1995).","journal-title":"Biochemistry"},{"key":"e_1_3_4_31_2","doi-asserted-by":"crossref","first-page":"525","DOI":"10.1016\/S0076-6879(96)66033-9","volume":"266","author":"Rost B","year":"1996","unstructured":"B Rost Methods Enzymol 266, 525\u2013559 (1996).","journal-title":"Methods Enzymol"},{"key":"e_1_3_4_32_2","doi-asserted-by":"crossref","first-page":"605","DOI":"10.1016\/S1097-2765(00)80159-8","volume":"2","author":"Weissenhorn W","year":"1998","unstructured":"W Weissenhorn, A Carfi, K H Lee, J J Skehel, D C Wiley Mol Cell 2, 605\u2013616 (1998).","journal-title":"Mol Cell"},{"key":"e_1_3_4_33_2","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1006\/viro.1998.9242","volume":"248","author":"Joshi S B","year":"1998","unstructured":"S B Joshi, R E Dutch, R A Lamb Virology 248, 20\u201334 (1998).","journal-title":"Virology"},{"key":"e_1_3_4_34_2","doi-asserted-by":"crossref","first-page":"366","DOI":"10.1038\/289366a0","volume":"289","author":"Wilson I A","year":"1981","unstructured":"I A Wilson, J J Skehel, D C Wiley Nature (London) 289, 366\u2013373 (1981).","journal-title":"Nature (London)"},{"key":"e_1_3_4_35_2","doi-asserted-by":"crossref","first-page":"12205","DOI":"10.1073\/pnas.92.26.12205","volume":"92","author":"Chen J","year":"1995","unstructured":"J Chen, S A Wharton, W Weissenhorn, L J Calder, F M Hughson, J J Skehel, D C Wiley Proc Natl Acad Sci USA 92, 12205\u201312209 (1995).","journal-title":"Proc Natl Acad Sci USA"},{"key":"e_1_3_4_36_2","doi-asserted-by":"crossref","first-page":"14306","DOI":"10.1073\/pnas.94.26.14306","volume":"94","author":"Carr C M","year":"1997","unstructured":"C M Carr, C Chaudhry, P S Kim Proc Natl Acad Sci USA 94, 14306\u201314313 (1997).","journal-title":"Proc Natl Acad Sci USA"},{"key":"e_1_3_4_37_2","doi-asserted-by":"crossref","first-page":"2041","DOI":"10.1128\/jvi.71.3.2041-2049.1997","volume":"71","author":"Poumbourios P","year":"1997","unstructured":"P Poumbourios, K A Wilson, R J Center, W El Ahmar, B E Kemp J Virol 71, 2041\u20132049 (1997).","journal-title":"J Virol"},{"key":"e_1_3_4_38_2","doi-asserted-by":"crossref","first-page":"1041","DOI":"10.1083\/jcb.137.5.1041","volume":"137","author":"Kanaseki T","year":"1997","unstructured":"T Kanaseki, K Kawasaki, M Murata, Y Ikeuchi, S Ohnishi J Cell Biol 137, 1041\u20131056 (1997).","journal-title":"J Cell Biol"},{"key":"e_1_3_4_39_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/BF00232676","volume":"146","author":"Chernomordik L","year":"1995","unstructured":"L Chernomordik, M M Kozlov, J Zimmerberg J Membr Biol 146, 1\u201314 (1995).","journal-title":"J Membr Biol"},{"key":"e_1_3_4_40_2","doi-asserted-by":"crossref","first-page":"383","DOI":"10.1016\/0092-8674(94)90344-1","volume":"76","author":"Kemble G W","year":"1994","unstructured":"G W Kemble, T Danielli, J M White Cell 76, 383\u2013391 (1994).","journal-title":"Cell"},{"key":"e_1_3_4_41_2","doi-asserted-by":"crossref","first-page":"995","DOI":"10.1083\/jcb.136.5.995","volume":"136","author":"Melikyan G B","year":"1997","unstructured":"G B Melikyan, S A Brener, D C Ok, F S Cohen J Cell Biol 136, 995\u20131005 (1997).","journal-title":"J Cell Biol"},{"key":"e_1_3_4_42_2","doi-asserted-by":"crossref","first-page":"1564","DOI":"10.1128\/jvi.70.3.1564-1569.1996","volume":"70","author":"Sagara Y","year":"1996","unstructured":"Y Sagara, Y Inoue, H Shiraki, A Jinno, H Hoshino, Y Maeda J Virol 70, 1564\u20131569 (1996).","journal-title":"J Virol"},{"key":"e_1_3_4_43_2","doi-asserted-by":"crossref","first-page":"276","DOI":"10.1038\/nsb0498-276","volume":"5","author":"Furuta R A","year":"1998","unstructured":"R A Furuta, C T Wild, Y Weng, C D Weiss Nat Struct Biol 5, 276\u2013279 (1998).","journal-title":"Nat Struct Biol"},{"key":"e_1_3_4_44_2","doi-asserted-by":"crossref","first-page":"986","DOI":"10.1128\/JVI.72.2.986-993.1998","volume":"72","author":"Rimsky L T","year":"1998","unstructured":"L T Rimsky, D C Shugars, T J Matthews J Virol 72, 986\u2013993 (1998).","journal-title":"J Virol"},{"key":"e_1_3_4_45_2","doi-asserted-by":"crossref","first-page":"555","DOI":"10.1038\/342555a0","volume":"342","author":"Spruce A E","year":"1989","unstructured":"A E Spruce, A Iwata, J M White, W Almers Nature (London) 342, 555\u2013558 (1989).","journal-title":"Nature (London)"},{"key":"e_1_3_4_46_2","doi-asserted-by":"crossref","first-page":"240","DOI":"10.1002\/j.1460-2075.1995.tb06997.x","volume":"14","author":"Wharton S A","year":"1995","unstructured":"S A Wharton, L J Calder, R W H Ruigrok, J J Skehel, D A Steinhauer, D C Wiley EMBO J 14, 240\u2013246 (1995).","journal-title":"EMBO J"},{"key":"e_1_3_4_47_2","doi-asserted-by":"crossref","first-page":"559","DOI":"10.1083\/jcb.133.3.559","volume":"133","author":"Danieli T","year":"1996","unstructured":"T Danieli, S L Pelletier, Y I Henis, J M White J Cell Biol 133, 559\u2013569 (1996).","journal-title":"J Cell Biol"},{"key":"e_1_3_4_48_2","doi-asserted-by":"crossref","first-page":"946","DOI":"10.1107\/S0021889891004399","volume":"24","author":"Kraulis P","year":"1991","unstructured":"P Kraulis J Appl Crystallogr 24, 946\u2013950 (1991).","journal-title":"J Appl Crystallogr"},{"key":"e_1_3_4_49_2","doi-asserted-by":"crossref","first-page":"505","DOI":"10.1016\/S0076-6879(97)77028-9","volume":"277","author":"Merritt E A","year":"1997","unstructured":"E A Merritt, D J Bacon Methods Enzymol 277, 505\u2013525 (1997).","journal-title":"Methods Enzymol"},{"key":"e_1_3_4_50_2","doi-asserted-by":"crossref","first-page":"946","DOI":"10.1006\/jmbi.1993.1648","volume":"234","author":"Lawrence M C","year":"1993","unstructured":"M C Lawrence, P M Colman J Mol Biol 234, 946\u2013950 (1993).","journal-title":"J Mol Biol"},{"key":"e_1_3_4_51_2","doi-asserted-by":"crossref","first-page":"281","DOI":"10.1002\/prot.340110407","volume":"11","author":"Nicholls A","year":"1991","unstructured":"A Nicholls, K A Sharp, B Honig Proteins 11, 281\u2013296 (1991).","journal-title":"Proteins"},{"key":"e_1_3_4_52_2","unstructured":"Kemp B. E. McPhee D. A. & Doherty R. R. (1988) Eur. Patent Appl. 88 312 216.0."}],"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.96.8.4319","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,6,7]],"date-time":"2022-06-07T00:44:39Z","timestamp":1654562679000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.96.8.4319"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1999,4,13]]},"references-count":52,"journal-issue":{"issue":"8","published-print":{"date-parts":[[1999,4,13]]}},"alternative-id":["10.1073\/pnas.96.8.4319"],"URL":"https:\/\/doi.org\/10.1073\/pnas.96.8.4319","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1999,4,13]]},"assertion":[{"value":"1998-11-19","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"1999-04-13","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}