Molecular and Cellular Biology

MOLECULAR AND CELLULAR BIOLOGY

VOLUME 6 e APRIL 1986 - NUMBER 4

Aaron J. Shatkin, Editor in Chief(1990) David J. L. Luck, Editor (1987) Paul S. Sypherd, Editor (1990) Roche Institute of Molecular Biology Rockefeller University University of California Nutley, N.J. New York, N.Y. Irvine Harvey F. Lodish, Editor (1986) Louis Siminovitch, Editor (1990) Harold E. Varmus, Editor (1989) Whitehead Institute for Biomedical Mount Sinai Hospital University of California Research Toronto, Canada San Francisco Cambridge, Mass. Joan A. Steitz, Editor (1990) Yale University New Haven, Conn.

EDITORIAL BOARD Frederick W. Alt (1987) Jack F. Greenblatt (1988) Steven McKnight (1986) Milton J. Schlesinger (1986) Arnold J. Berk (1988) Leonard P. Guarente (1988) Janet E. Mertz (1987) Fred Sherman (1988) Alan Bernstein (1987) James E. Haber (1987) Robert L. Metzenberg (1988) Anna Marie Skalka (1986) Barbara K. Birshtein (1987) Hidesaburo Hanafusa (1986) Robert K. Mortimer (1988) Arthur Skoultchi (1988) J. Michael Bishop (1987) Ari Helenius (1987) Paul Neiman (1986) Frank Solomon (1988) Michael R. Botchan (1987) Ira Herskowitz (1987) Joseph R. Nevins (1987) Pamela Stanley (1988) David Botstein (1987) James B. Hicks (1986) Carol Newlon (1988) Bruce Stillman (1988) Bruce P. Brandhorst (1987) Alan Hinnebusch (1988) Harvey L. Ozer (1988) Bill Sugden (1988) James R. Broach (1988) Michael J. Hollabd (1987) Mary Lou Pardue (1988) Jack Szostak (1987) Joan Brugge (1988) Greg Hollis (1987) Carl S. Parker (1987) Lawrence H. Thompson (1988) Mario R. Capecchi (1987) Anita K. Hopper (1988) Ira H. Pastan (1988) Shirley M. Tilghman (1987) John A. Carbon (1987) Peter M. Howley (1988) David Patterson (1988) Robert Tjian (1987) Lawrence A. Chasin (1988) Tony Hunter (1986) Gianni Piperno (1988) Jonathan R. Warner (1987) Nam-Hai Chua (1988) Larry Kedes'(1988) John R. Pringle (1988) Alan M. Weiner (1987) Don W. Cleveland (1987) Robert S. Kerbel (1988) Jean-Paul Revel (1988) Harold Weintraub (1988) Christopher Coleclough 1987) Barbara Knowles (1986) Daniel B. Rifkin (1988) Reed B. Wickner (1988) Terrance G. Cooper (1987) Marilyn Kozak (1988) G. S. Roeder (1988) Fred Winston (1988) Elizabeth A. Craig (1988) Monty Krieger (1986) Robert G. Roeder (1988) Owen Witte (1988) James E. Dahlberg (1987) Arnold J. Levine (1987) Naomi E. Rosenberg (1988) Elton T. Young (1987) James E. Darnell, Jr. (1988) Susan Lindquist (1987) Norman P. Salzman (1988) Michael Young (1988) G. N. Godson (1987) Paul T. Magee (1988) Paul Schedl (1987) Edward Ziff (1988) Michael Green (1988) James Manley (1986) Randy W. Schekman (1988)

Helen R. Whiteley, Chairman, Publications Board Linda M. Illig, Managing Editor, Journals Linda M. Illig, Production Editor Molecular and Cellular Biology (ISSN 0270-7306) is devoted to the advancement and dissemination offundamental knowledge concerning the molecular biology of eucaryotic cells, of both microbial and higher organisms. Instructions to authors are published in the January issue each year; reprints are available from the editors and the Publications Department. The journal is published monthly, one volume per year. The nonmember subscription price is $150 per year; single copies are $21. The member subscription price is $41 (foreign $54 [surface rate]) per year; single copies are $7. Correspondence relating to subscriptions, reprints, defective copies, availability of back issues, lost or late proofs, disposition of submitted manuscripts, and general editorial matters should be directed to the ASM Publications Department, 1913 I St., NW, Washington, DC 20006 (area 202 833-9680). 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 offailure to report an address change or for issues "missing from files" will not be allowed. Second-class postage paid at Washington, DC 20006, and at additional mailing offices. POSTMASTER: Send address changes to Molecular and Cellular Biology, ASM, 1913 I St., NW, Washington, DC 20006. Made in the United States of America. Copyright © 1986, American Society for Microbiology. at: VIl itE'K r', ( '1I4 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 Inc., 21 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

Aaronson, Stuart A., 1002 Friedmann, Theodore, 1141 MacKay, Sally L. D., 1261 Sarasin, Alain, 1102 Agarwal, Kan, 1032 Magun, Bruce E., 1088 Sato, Kenzo, 1032 Agha, Mounzer, 1172 Garrison, Preston N., 1179 Mahowald, Anthony P., 1187 Sauer, Monica K., 1304 Anderson, G. Mark, 1244 Gelinas, Richard, 1108 Mamon, Harvey, 1172 Scangos, George, 1339 Armilei, Genny, 1095 Geraghty, Dan, 1074 Marlor, Robin L., 1129 Schatzman, Randall C., 1329 Aronow, Bruce, 12% Gerner, Eugene W., 1088 Martin, Nancy C., 1058 Seidman, J. G., 1315 Ash, John Frederick, 1164 Gorman, Marnell C., 1095 Mathis, Sandra A., 1179 Senear, Allen W., 1253 Astell, Caroline R., 1352 Greenberg, Michael E., 1050 McCoy, Melissa S., 1326 Sharp, Philip A., 1204 Groudine, Mark, 1108 McKnight, G. Stanley, 1010 Shaw, Stephen, 1074 Baek, Kwang-Hee, 1032 Gumucio, Deborah L., 969 Meisler, Miriam H., %9 Shimizu, Yoji, 1074 Barnes, Larry D., 1179 Miller, Oscar L., Jr., 1148 Shin, Seung-il, 1268 Benoit, Annie, 1102 Hamer, Dean H., 1158 Moore, Patrick, 1164 Sollner-Webb, Barbara, 1228 Bieberich, Charles, 1339 Hammer, Robert E., 1010 Morgan, Martha, 1164 Stamatoyannopoulos, George, Bikel, Ilan, 1172 Hanafusa, Hidesaburo, 1065 Mulligan, Richard C., 1204 1108 Bishop, J. Michael, 1329 Hannink, Mark, 1304, 1343 Murre, Cornelis, 1315 Stanley, Pamela, 1268 Bolden, Arthur H., 1135 Hauswirth, William W., 1261 Stinson, Leslie, 1187 Boltax, Jay, 1172 Hayashi, Kenshi, 1349 Nagao, Minako, 1349 Subramani, 1320 Botchan, Michael R., 1283 Hermanowski, Anne L., 1050 Nalin, Carlo M., 1135 Suresh, Boyce, Frederick M., 1244 Hollingsworth, Margaret J., Naumovski, Louie, 1218 Sugimura, Takashi, 1349 Brinster, Ralph L., 1010 1058 Swanstrom, Ronald, 1334 Brown, Eugene L., 1172 Hollingsworth, Paula, 12% Ochiai, Masako, 1349 Burakoff, S. J., 1315 Olivo, Paul D., 1261 Tahira, Tomoko, 1349 Button, Linda L., 1352 Idzerda, Rejean L., 1010 Orr, Harry, 1074 Tam, James P., 1065 Itin, Ahuva, 1276 Tanaka, Kenichi, 1339 Calame, Kathryn, 1352 Ito, Ryoji, 1032 Palter, Karen B., 1187 Terracol, Regine, 1023 Cepko, Constance L., 1204 Papayannopoulou, Thalia, Thiele, Dennis J., 1158 Chang, Shin C., 1235 James, C. David, 976 1108 Tsai, Charles C., 969 Company, Mahshid, 1334 Jat, Parmjit S., 1204 Parker, Kenneth C., 1315 Tsuchida, Nobuo, 1349 Corces, Victor G., 1129 Jay, Gilbert, 1339 Parkhurst, Susan M., 1129 Craig, Elizabeth A., 1187 Johnson, Michael D., 1164 Patrick, Joseph, 12% Ullman, Buddy, 12% Jolly, Douglas J., 1141 Pauw, Peter G., 1164 Dahlberg, Albert E., 1044 Peden, Keith W. C., 1117 Wang, James C., 985 Darlington, Gretchen J., 9 Kakkis, Emil, 1352 Peretz, Mary, 1108 Ward, Cheryl A., 1135 DeFranco, Donald, 993 Kalka, Timothy, 1164 Poonian, Mohindar S., 1135 Watanabe, Michiko, 1187 DeMars, Robert, 1074 Kavathas, Paula, 1074 Prehn, John, 1352 Weinberg, Robert A., 1326 Dixon, Richard A. F., 1117 Kelly, Thomas, 1117 Privalsky, Martin L., 1329 Weissbach, Arthur, 1135 Donoghue, Daniel J., 1304, Keshet, Eli, 1276 Prud'homme, Nicole, 1023 1343 Koller, Beverly, 1074 Widelitz, Randall B., 1088 Driller, Jonathan P., 1315 Reiss, Carol S., 1315 Wiley, Don C., 1315 Lacal, Juan Carlos, 1002 Rio, Donald C., 1283 Willis, Randall C., 1141 Elder, James T., 1108 Laipis, Philip J., 1261 Ripka, James, 1268 Windle, Jolene, 1228 Errede, Beverly, 1334 Lee, Amy S., 1235 Robbins, Paul D., 1283 Evan, Gerard I., 1329 Leffak, Michael, 976 Romero, Daniel P., 1044 Yagi, Mayumi, 1108 Lewis, James B., 1253 Rowe, Thomas C., 985 Yamamoto, Keith R., 993 Feldman, Ricardo A., 1065 Li, Joachim J., 1117 Rusk, Cindy D., 1244 Yarger, James G., 1095 Fineman, Robert M., 1164 Lin, Augustine Y., 1235 Yuan, Dorothy, 1015 Freytag, Svend O., 1244 Liu, Leroy F., 985 Saffer, Linda D., 1148 Friedberg, Errol C., 1218 Livingston, David M., 1172 Samuelson, Linda C., 969 Ziff, Edward B., 1050 If you are working in the area ofeucaryotic cell biology, then you need EDITOR IN CHIEF: Aaron J. Shatkin EDITORS: Harvey F. Lodish, David J. L. Luck. Louis Siminovitch, Joan A. Steitz, Paul S. Sypherd, Harold E. Varmus

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