JOURNAL OF VOLUME 67 * SEPTEMBER 1993 * NUMBER 9 Arnold J. Levine, Editor in Chief (1994) Peter M. Howley, Editor (1998) Vincent R. Racaniello, Editor (1997) Princeton University National Cancer Institute Columbia University Princeton, N.J. Bethesda, Md. New York, N.Y. Robert A. Lamb, Editor (1997) John M. Coffin, Editor (1996) Northwestern University Thomas E. Shenk, Editor (1994) Tufts University Medical School Evanston, Ill. Princeton University Boston, Mass. Princeton, N.J. Michael B. A. Oldstone, Editor (1994) Ronald C. Desrosiers, Editor (1998) Scripps Clinic & Research Foundation Inder M. Verma, Editor (1998) Harvard Medical School La Jolla, Calif. The Salk Institute Boston, Mass. Carol Prives, Editor (1996) San Diego, Calif. Columbia University New York, N. Y EDITORIAL BOARD Rafi Ahmed (1994) Paul D. Friesen (1994) Edward S. Mocarski (1993) Manfred H. Schubert (1993) James Alwine (1994) Denise A. Galloway (1995) Peter Model (1995) Bartholomew M. Sefton (1994) Carl C. Baker (1994) Don Ganem (1994) Bernard Moss (1995) Bert L. Semler (1995) Amiya K. Banerjee (1993) Costa P. Georgopoulos (1995) Richard W. Moyer (1995) David A. Shafritz (1994) Kenneth I. Berns (1994) Joseph C. Glorioso (1995) James Mullins (1993) Yosef Shaul (1995) Joseph B. Bolen (1994) Harry B. Greenberg (1995) Brian R. Murphy (1994) Saul J. Silverstein (1994) Thomas J. Braciale (1994) Hidesaburo Hanafusa (1995) Nicholas A. Muzyczka (1993) John Brady (1994) Ed Harlow (1993) Gerald Myers (1995) Daniel T. Simmons (1995) Thomas R. Broker (1995) Ari H. Helenius (1993) Opendra Narayan (1994) Anna Marie Skalka (1993) Michael J. Buchmeier (1995) Virginia S. Hinshaw (1993) Neal Nathanson (1993) Joseph Sodraski (1995) Robert Callahan (1994) James M. Hogle (1994) Jay A. Nelson (1994) Nahum Sonenberg (1993) Barrie J. Carter (1993) John J. Holland (1993) Joseph R. Nevins (1994) Arne Stenlund (1995) Mark Challberg (1995) Kathryn V. Holmes (1994) Dennis O'Callaghan (1995) Mark F. Stinski (1995) Irvin S. Y. Chen (1993) Nancy Hopkins (1995) Peter Palese (1994) James Strauss (1993) Bruce W. Chesebro (1994) Alice S. Huang (1993) Enzo Paoletti (1994) Bill Sugden (1993) Donald M. Coen (1995) Stephen H. Hughes (1994) Takis Papas (1993) Jesse Summers (1995) Gary H. Cohen (1994) Eric Hunter (1993) J. Thomas Parsons (1995) Ron Swanstrom (1993) Charles N. Cole (1995) Tony Hunter (1995) David J. Pintel (1995) Peter J. Tattersall (1995) Peter L. Collins (1994) Nancy A. Jenkins (1995) Abraham Pinter (1994) John M. Taylor (1993) Richard W. Compans (1993) Richard A. Katz (1993) James Pipas (1993) Howard M. Temin (1994) Richard C. Condit (1995) Jack D. Keene (1994) Lewis I. Pizer (1993) Mary J. Tevethia (1993) Neal G. Copeland (1995) Thomas J. Kelly (1994) Nancy Raab-Traub (1993) Satvir S. Tevethia (1994) Richard J. Courtney (1995) Elliott Kieff (1993) Arnold B. Rabson (1993) David A. Thorley-Lawson (1994) Clyde S. Crumpacker II (1994) Karla Kirkegaard (1993) R. Frank Ramig (1994) Bryan R. Cullen (1993) Geoffrey R. Kitchingman (1995) Dan S. Ray (1995) Paula Traktman (1995) Thomas Curran (1994) Daniel F. Klessig (1994) Alan Rein (1993) Philip N. Tsichlis (1995) Samuel Dales (1994) David M. Knipe (1994) Solon L. Rhode (1995) Kenneth L. Tyler (1994) Daniel DiMaio (1994) Hsing-Jien Kung (1993) William S. Robinson (1995) Luis V. Villarreal (1994) Walter Doerfler (1995) Ching-Juh Lai (1993) Bernard Roizman (1994) Peter K. Vogt (1993) Elvera Ehrenfeld (1995) Michael Lai (1994) John K. Rose (1994) Edward K. Wagner (1995) Robert N. Eisenman (1994) Jonathan Leis (1994) Craig Rosen (1993) Robert G. Webster (1993) John Elder (1993) Norman L. Letvin (1995) Naomi Rosenberg (1995) Raymond M. Welsh (1994) Michael Emerman (1995) Maxine Linial (1994) Roland R. Rueckert (1994) Gail Wertz (1994) Suzanne U. Emerson (1995) David M. Livingston (1994) Norman P. Salzman (1993) J. Lindsay Whitton (1995) Lynn W. Enquist (1994) Douglas R. Lowy (1995) Charles E. Samuel (1995) Reed B. Wickner (1994) Mary K. Estes (1995) James L. Manley (1995) Richard Jude Samulski (1995) John W. Wills (1995) Hung Fan (1994) Malcolm A. Martin (1995) Dorothea L. Sawicki (1994) Eckard Wimmer (1994) Ellen Fanning (1994) William S. Mason (1994) Priscilla A. Schaffer (1993) Flossie Wong-Staal (1993) Bernard Fleckenstein (1993) Michael B. Mathews (1994) Heinz Schaller (1995) Moshe Yaniv (1995) S. Jane Flint (1993) A. Dusty Miller (1994) Sondra Schlesinger (1995) Charles Hamish Young (1995) William R. Folk (1994) Lois K. Miller (1994) Robert J. Schneider (1994) Harald zur Hausen (1995)

Barbara H. Iglewski, Chairnan, Publications Board Linda M. Illig, Director, Journals Judith Nedrow, Production Editor Arthur Gelmis, Assistant Production Editor The Journal of Virology, a publication of the American Society for (ASM), 1325 Massachusetts Ave., N.W., Washington, DC 20005-4171, is devoted to the dissemination of fundamental knowledge concerning viruses of bacteria, plants, and animals. Investigators are invited to submit reports of original research in all areas of basic virology, including , biophysics, , , morphology, physiology, and pathogenesis and immunity. Instructions to authors are published in the January issue each year; reprints are available from the editors and the Journals Division. The Journal is issued monthly, one volume per year. The nonmember print subscription prices are $362 (U.S.) (Canadians add 7% GST) and $432 (other countries) per year; single copies are $40 (Canadians add 7% GST). The member print subscription prices are $81 (U.S.) (Canadians add 7% GST) and $106 (other countries); single copies are $10 (Canadians add 7% GST). For prices of CD-ROM versions, contact the Subscriptions Unit, ASM. Correspondence relating to subscriptions, defective copies, missing issues, and availability of back issues should be directed to the Subscriptions Unit, ASM; correspondence relating to reprint orders should be directed to the Reprint Order Unit, ASM; and correspondence relating to disposition of submitted manuscripts, proofs, and general editorial matters should be directed to the Journals Division, American Society for Microbiology, 1325 Massachusetts Ave., N.W., Washington, DC 200054171. Phone: (202) 737-3600. Claims for missing issues from residents of the United States, Canada, and Mexico must be submitted within 3 months after publication of the issues; residents of all other countries must submit claims within 6 months of publication of the issues. Claims for issues missing because of failure to report an address change or for issues "missing from files" will not be allowed. Second-class postage paid at Washington, DC 20005, and at additional mailing offices. POSTMASTER: Send address changes to Journal of Virology, ASM, 1325 Massachusetts Ave., N.W., Washington, DC 20005-4171. Made in the U.S.A. Printed on acid-free paper. ISSN 0022 Copyright © 1993, American Society for Microbiology. CODEN: JOVLAM All Rights Reserved. The code at the top of the first page of an article in this journal indicates the copyright owner's consent that copies of the article may be made for personal use or for personal use of specific clients. This consent is given on the condition, however, that the copier pay the stated per-copy fee through the Copyright Clearance Center, 27 Congress St., Salem, MA 01970, for copying beyond that permitted by Sections 107 and 108 of the U.S. Copyright Law. This consent does not extend to other kinds of copying, such as copying for general distribution, for advertising or promotional purposes, for creating new collective works, or for resale. Author Index

Aavik, Einari, 5681 Gebhard, Douglas H., 5175 Marshak, Daniel R., 5206 Sandler, Abby B., 5079 Abell, Barbara A., 5496 Ghazal, Peter, 5595 Martin, J. M., 5269 Santaren, Juan F., 5126 Alcami, Antonio, 5463 Ghosh, Ananta K., 5153 Martinez-Pomares, Luisa, 5450 Sargan, D., 5187 Allen, D., 5187 Gillespie, David A. F., 5487 Mashiah, Pnina, 5640 Schiller, John T., 5303 Almazan, Fernando, 5312 Gluzman, Yakov, 5206 Mason, Peter W., 5139 Schlegel, Richard, 5303 Almendral, Jose M., 5126 Goldstein, David J., 5303 Masternak, Krzysztof, 5394 Schleiss, Mark R., 5514 Angulo, Ana, 5463 Goodart, Sheryl A., 5109 Maurer, Bernd, 5411 Schutten, M., 5216 Arias, Carlos F., 5253 Gooding, Linda R., 5289 McConnell, I., 5187 Sitbon, Marc, 5146, 5478 Ashelford, S., 5216 Guzowski, John F., 5098, 5109 McKeating, J. A., 5216 Smith, Michael J., 5522 Babiuk, Lorne A., 5664 Hahn, Heidi, 5411 McVey, Duncan, 5206 Spalholz, Barbara A., 5079 Bai, Mei, 5198 Hakkarainen, Kati, 5681 Mendez, Ernesto, 5253 Sparer, Tim, 5289 Baker, Carl C., 5605 Hansen, Mark, 5163 Merza, Malik, 5321 Staknis, David, 5419 Balfe, P., 5216 Harfe, Brian, 5198 Messerle, Martin, 5360 Stamatatos, Leonidas, 5635 Balthesen, Monika, 5360 Hauser, H., 5579 Meyer, William J., 5117 Stegeman-Olsen, Jenny, 5163 Balzarini, Jan, 5353 Hawker, Kim L., 5487 Miki, Toru, 5640 Stenberg, Richard M., 5595 Barklis, Eric, 5163 Hennigan, Robert F., 5487 Milich, Lynn, 5623 Stern, Richard J., 5450 Barksdale, Sarah Kay, 5605 Hermiston, Terry W., 5289 Miller, A. Dusty, 5346 Sugden, B., 5269 Barrell, Barclay G., 5502 Hilfinger, John M., 5522 Miller, Daniel G., 5346 Sunil-Chandra, N. P., 5247 Baunach, Gerald, 5411 Hirt, Bernhard, 5660 Miller, Lois K., 5260 Swanstrom, Ronald, 5623 Beauparlant, Pierre, 5235 Hiscott, John, 5235 Mittal, Rakesh, 5656 Szabo, Csilla, 5704 Bennett, J., 5216 Hoffmann, Stefan, 5595 Monini, Paolo, 5668 Takeuchi, Kaoru, 5585 Berger, Lloyd, 5206 Honnen, William J., 5692 Moormann, R. J. M., 5435 Tanimura, Akira, 5375 Bird, P., 5187 Hooper, Jay W., 5339 Moyer, Richard W., 5450 James Tarpley, W. Gary, 5353 Blacklaws, B., 5187 Hoover, Edward A., 5153 Mullins, I., 5153, 5681 Tegtmeyer, Peter, 5206 Blitz, Ira L., 5668 Hopkins, J., 5187 Naito, Satoshi, 5328 Teshima, Hisako, 5375 Boeye, A., 5299 Huang, Cheng-Jin, 5109 Nash, A. A., 5247 The, Inge, 5226 Brown, A. Leigh, 5216 Hulst, M. M., 5435 Nelson, Jay A., 5595 Tilley, Shermaine A., 5692 Brown, Dennis T., 5496 Hunter, Eric, 5279 Noiman, Silvia, 5640 Tompkins, Mary B., 5175 Brown, Fred, 5139 Inada, Toshiki, 5698 Ohno, Takeshi, 5328 Tong, Shu-Ping, 5402, 5651 Broyles, Steven S., 5677 Ishikawa, Masayuki, 5328 Orsoni, Sabine, 5478 Trepo, Christian, 5402, 5651 Bunch, Thomas, 5139 M. 5538 Ozanne, Bradford W., 5487 Tripp, Ralph A., 5289 Burny, Arsene, 5321 Jabbar, Abdul, Jacobson, Jennie, 5383 Pahl, Armin, 5426 Tronick, Steven R., 5640 Cadd, Tamarra L., 5647 Jelinek, Laura, 5163 Parslow, Tristram G., 5617 Umene, Kenichi, 5685 Callebaut, Isabelle, 5321 Johnson, Calvin M., 5175 Passarelli, A. Lorena, 5260 Camarasa, Maria-Jose, 5353 Johnston, Patrick B., 5279 Pater, Alan, 5656 van den Heuvel, Sander J. L., Cao, Jianhong, 5514 Johnston, Robert E., 5117 Pater, Mary M., 5656 5226 Cao, Xuemei, 5572 Jones, Russell S., 5163 Patterson, Jean L., 5647 Vande Pol, Scott B., 5079 Cassai, Enzo, 5668 Jonsson, Colleen B., 5562 Perez-Perez, Maria-Jesus, 5353 van der Eb, Alex J., 5226 Casse-Ripoll, Huguette, 5529 Jupp, Ray, 5595 Peterlin, B. Matija, 5617 van Laar, Theo, 5226 Cheng-Mayer, Cecilia, 5635 Karlsson, Anna, 5353 Pinter, Abraham, 5692 Vamier, Oliviero E., 5367 Clark, Nina M., 5522 Kay, Alan, 5651 Pinto, Lawrence H., 5585 Vass, William C., 5303 Coen, Donald M., 5383, 5419 Keenan, Marie C., 5647 Pintzas, Alex, 5487 Veis, D., 5269 Cohen, Bruce D., 5303 Kikuchi, Hitoshi, 5698 Portetelle, Daniel, 5321 Vincent, Martin J., 5538 Corbin, Antoine, 5146, 5478 Kim, Young Ki, 5704 Pozo, Francoise, 5478 Vifiuela, Eladio, 5312, 5463 Cox, Graham J. M., 5664 Knipe, David M., 5383 Vitvitski, Ludmila, 5402, 5651 Cullen, Bryan R., 5617 Raja, Nicholas U., 5538 Kollmus, H., 5579 Ramirez, Juan C., 5126 Voneche, Veronique, 5321 De Clercq, Erik, 5353 Korsmeyer, S. J., 5269 Rawlinson, William D., 5502 Wagner, Edward K., 5098, Degnin, Catherine R., 5514 Kosz-Vnenchak, Magdalena, Ray, Satyajit, 5206 Delaet, 5299 5109 I., 5383 Rayed, Fouad, 5367 Wang, Chang, 5585 Depto, Alison, 5595 Kranz, Manuela, 5411 Reddehase, Matthias J., 5360 Weidle, U. H., 5579 Dewhurst, Steve, 5681 Krchnak, Viktor, 5321 Reil, H., 5579 Weldon, Robert A., Jr., 5550 Digard, Paul, 5419 Krohn, Kai J. E., 5681 Rein, Alan, 5443 Wen, Yu-Mei, 5402 Dodon, Madeleine Duc, 5529 Kuhn, Richard J., 5572 5367 John Reina, Salvatore, Wensvoort, G., 5435 Dubay, W., 5279 Kunz, Beatrice, 5394 Reinhart, Todd A., 5153 Westra, D. F., 5435 Eglitis, Martin A., 5472 Lamb, Robert A., 5585 Reitz, Marvin, 5367 Wildeman, Alan G., 5206 Ehtisham, S., 5247 Lee, Wen-Chi, 5088 Rethwilm, Axel, 5411 Wills, John W., 5550 Eiden, Maribeth V., 5472 Li, Jing, 5677 Reyburn, H. T., 5187 Willwand, Kurt, 5660 English, Robert V., 5175 Li, Ji-Su, 5402, 5651 Rice, Marcia K., 5109 Wilson, Carolyn A., 5472 Fields, Bernard N., 5339 Li, Yonghong, 5260 Rice, Nancy, 5235 Wimmer, Eckard, 5572 Flugel, Rolf M., 5426 L6pez, Susana, 5253 Richardson, Jennifer, 5478 Wittek, Riccardo, 5394 Freimuth, Paul, 5198 Lowy, Douglas R., 5303 Rieder, Elizabeth, 5139 Wobbe, Kristin K., 5419 Fu, William, 5443 Lucia-Jandris, Patricia, 5339 Rivlin, Michal, 5640 Wold, William S. M., 5289 Fujisawa, Jun-ichi, 5375 Luo, Ying, 5617 Roberts, Susan J., 5279 Fuller, A. Oveta, 5088 Madore, Steven J., 5617 Rodriguez, Javier M., 5312 Yamazaki, Shudo, 5698 Fumiere, Olivier, 5321 Mager, Anne, 5321 Rodriguez, Jose F., 5312 Yafiez, Rafael J., 5312 Gallo, Robert C., 5367 Maguer, Veronique, 5529 Rosin-Arbesfeld, Rina, 5640 Yaniv, Abraham, 5640 Garces, Javier, 5394 Mammerickx, Marc, 5321 Roth, Monica J., 5562 Yoshida, Mitsuaki, 5375 Gard, Elisabeth, 5367 Margolin, Barry, 5623 Roulston, Anne, 5235 Zamb, Tim J., 5664 Gazit, Arnona, 5640 Mark, Willie H., 5704 Rutledge, Laura, 5303 Zavada, Jan, 5321 Gazzolo, Louis, 5529 Markham, Phillip, 5367 Sadaie, Reza, 5681 Zhang, Qing, 5402 Geballe, Adam P., 5514 Markovitz, David M., 5522 Salzwedel, Karl, 5279 Zolla-Pazner, S., 5216 i Howard Hughes Medical Institute Fellowships for Biological and Biomedical Sciences

The Howard Hughes Medical Institute announces the 1994 competitions for fellowship programs that support training in fundamental biological and biomedical research. Awards, based on international competitions, focus on research directed to understand- ing basic biological processes and disease mechanisms. Fellowships may be held at aca- demic or not-for-profit research institutions.

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