MOLECULAR AND CELLULAR BIOLOGY VOLUME 10 * MAY 1990 * NUMBER 5 Aaron J. Shatkin, Editor in Chief (1990) Louis Siminovitch, Editor (1990) Center for Advanced Mount Sinai Hospital Biotechnology and Medicine David J. L. Luck, Editor (1992) Toronto, Canada Piscataway, N.J. Rockefeller University Shirley M. Tilghman, Editor Don W. Cleveland, Editor (1994) New York, N. Y. (1993) The Johns Hopkins University Steven L. McKnight, Editor (1992) Princeton University Baltimore, Md. Carnegie Institution ofWashington Princeton, N.J. Anita K. Hopper, Editor (1994) Baltimore, Md. Alan M. Weiner, Editor (1993) The Milton S. Hershey Medical Center Randy W. Schekman, Editor Yale University Pennsylvania State University (1992) New Haven, Conn. Hershey, Pa. University of California Owen N. Witte, Editor (1993) Tony Hunter, Editor (1993) Berkeley Molecular Biology Institute The Salk Institute University of California San Diego, Calif. Los Angeles EDITORIAL BOARD Frederick W. Alt (1990) Mary P. Edmonds (1990) Monty Krieger (1992) Naomi E. Rosenberg (1991) Susan Berget (1990) Robert N. Eisenman (1991) Elizabeth Lacy (1990) Rodney Rothstein (1990) Arnold J. Berk (1991) Sarah C. R. Elgin (1991) Alan Lambowitz (1990) Norman P. Salzman (1991) Alan Bernstein (1990) Scott Emr (1991) Lester F. Lau (1992) Paul Schedl (1990) Barbara K. Birshtein (1990) Walton L. Fangman (1991) Michael Lenardo (1991) Milton J. Schlesinger (1992) J. Michael Bishop (1990) Thomas D. Fox (1990) Arthur D. Levinson (1990) Matthew P. Scott (1992) Elizabeth H. Blackburn (1991) Mary-Jane Gething (1990) Susan Lindquist (1990) Charles J. Sherr (1991) Jef D. Boeke (1991) Stephen P. Goff (1992) Douglas Lowy (1990) Arthur Skoultchi (1991) Michael R. Botchan (1990) Jack F. Greenblatt (1991) Paul T. Magee (1991) Frank Solomon (1991) David Botstein (1990) Rudolf Grosschedl (1992) James Manley (1992) Michael B. Sporn (1991) Bruce P. Brandhorst (1990) Leonard P. Guarente (1991) Kunihiro Matsumoto (1991) Allan C. Spradling (1991) Marjorie C. Brandriss (1991) Christine Guthrie (1992) Frank McCormick (1992) Karen U. Sprague (1992) Rodrigo Bravo (1992) James E. Haber (1990) Janet E. Mertz (1990) Pamela Stanley (1991) Kathryn Calame (1991) Hidesaburo Hanafusa (1992) N. Ronald Morris (1992) Nat L. Sternberg (1992) Judith Campbell (1992) Leland D. Hartwell (1990) Bernardo Nadal-Ginard (1990) Bruce Stillman (1991) Mario R. Capecchi (1990) Nathaniel Heintz (1991) Paul Neiman (1992) Kevin Struhl (1992) John A. Carbon (1990) Ari Helenius (1990) Joseph R. Nevins (1990) Kenneth D. Stuart (1991) Marian Carlson (1992) Steven Henikoff (1991) Carol Newlon (1991) Bill Sugden (1991) C. Thomas Caskey (1990) Ira Herskowitz (1990) Mary Ann Osley (1990) Lawrence H. Thompson (1991) Lawrence A. Chasin (1991) Alan Hinnebusch (1991) Harvey L. Ozer (1991) Geoffrey Wahl (1992) Nam-Hai Chua (1991) Michael J. Holland (1990) Mary Lou Pardue (1991) Randolph Wall (1992) Jonathan A. Cooper (1992) Greg Hollis (1990) David Patterson (1991) Peter Walter (1990) Nicholas Cowan (1990) Peter M. Howley (1991) Gianni Piperno (1991) Jonathan R. Warner (1990) Elizabeth A. Craig (1991) Stephen H. Hughes (1992) John R. Pringle (1991) Reed B. Wickner (1991) Thomas Curran (1991) Mark Johnston (1991) Randall R. Reed (1992) Lewis T. Williams (1991) Mark Davis (1990) Katherine A. Jones (1992) Steven I. Reed (1991) Fred Winston (1991) Thomas Donahue (1992) Daniel Klessig (1992) Jean-Paul Revel (1991) Elton T. Young (1990) Gideon Dreyfuss (1990) Marilyn Kozak (1991) Jasper D. Rine (1991) Michael Young (1991) Helen R. Whiteley, Chairman, Publications Board Linda M. Ihig, Managing Editor, Journals Catherine E. 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Akeson, Richard, 2012 Franke, Jakob, 1921 Linial, Maxine L., 1891 Sawai, Shoji, 2017 Alcorta, David A., 2413 French, Randall P., 2081 Linsley, Peter S., 1882 Sax, Christina M., 2349 Alt, Frederick W., 2096 Frontali, C., 2423 Lipsick, Joseph S., 2285 Saxe, Stephen A., 2367 Altanchimeg, Rencendorj, London, Lucille, 1901 Schmidt, Ann, 2176 2432 Gaffney, Robert, 1931 Schuster, Wolfgang, 2428 Amrein, Kurt E., 1853 Gallego, Maria E., 2133 Marck, Christian, 2437 Sefton, Bartholomew M., 1853 Anraku, Yasuhiro, 2214 Gashler, Andrea, 1931 Martin, Christopher, 1908 Sentenac, Andrd, 2437 Aronoff, Rachel, 1891 Gaugler, Luc, 1959 Martin, Debra J., 1950 Shago, Mary, 2335 Azizkhan, Jane C., 2111 Giguere, Vincent, 2335 Matsushime, Hitoshi, 2261 Shaw, Andrey S., 1853 Glaser, Scott M., 1873 McDonald, Vicki L., 1969 Shay, Jerry W., 2027 Babiss, Lee E., 2027 Glass, Charles A., 2164 McDonnell, Timothy J., 1901 Sherr, Charles J., 2407 Ballesta, Juan P. G., 2182 Goridis, Christo, 1959 McKearn, John P., 1901 Shibuya, Masabumi, 2261 Bally-Cuif, Laure, 1959 Grant, Barbara J., 2164 McKiernan, Martin, 1931 Shortle, David, 2308 Baltimore, David, 2327 Green, Janell M., 1969 Memet, Sylvie, 2049 Shoyab, Mohammed, 1969 Bandyopadhyay, Ram, 2060 Miller, Brian R., 1873 Simpson, Robert T., 2247 Barriocanal, Javier G., 2294 Hall, Anne L., 1921 Mitchell, Aaron P., 2104 Smith, Harold E., 2104 Barta, Endre, 2432 Hammond, Craig, 1853 Morris, Charles F., 1931 Spear, David H., 2315 Baum, Mary P., 1863 Hartwell, Leland H., 2202 Morrison, Deborah K., 2359 Steiner, Bart, 1891 Beltrame, Monica, 2341 Hatfield, Dolph, 1940 Mueller, LeMoyne, 2154 Stewart, Valerie, 2096 Bennett, Jeffrey L., 2191 Hay, Rick V., 1931 Stratling, Wolf H., 2302 Benvenisty, Nissim, 2418 Herrick, David, 2269 Nadal-Ginard, Bernardo, 2133 Strommer, Judith N., 2090 Bernards, Rene, 2012 Hiebert, Scott W., 1989 Nagata, Shigekazu, 2002 Sukhatme, Vikas P., 1931 Bianchi, Marco E., 2341 Hiesel, Rudolf, 2428 Neubauer, Michael G., 1882, Sullivan, Kevin F., 2164 Biemann, Hans-Peter N., 2122 Hinnebusch, Alan G., 2294 1969 Sweet, Laurel J., 2413 Blackburn, Elizabeth H., 2070 Hirsch, Marie-Rose, 1959 Ng, Davis T. W., 1989 Szab6, Piroska, 2432 Blasband, Andrew J., 2111 Hirschfeld, Steven, 2041 Nishizawa, Mikio, 2002 Bolen, Joseph B., 2035 Hockenberry, David, 1901 Nomura, Masayasu, 2049 Bosze, Zsuzsa, 2432 Nunez, Gabriel, 1901 Bowen-Pope, Daniel F., 2237 Ibanez, Carlos E., 2285 Takagi, Nobuo, 2261 Bozzoni, Irene, 2437 Iman, Deborah S., 2027 Ochs, Vincent, 1882 Tan, Eng M., 2164 Brawerman, George, 2060 Ogawa, Nobuo, 2224 Jackson, Catherine L., 2202 Tanaka, Kenji, 2214 Brennicke, Axel, 2428 Okamura, Sara, 1908 Tate, Peri, 2335 Buhler, Jean-Marie, 2049 Jacobson, Allan, 2269 Ortiz, Daniel F., 2090 Jacobson, K. Bruce, 1940 Teruya, Julie H., 2315 Oshima, Yasuji, 2224 Todaro, George J., 1969 Cao, Xinmin, 1931 Jinno, Atsushi, 2261 Ostertag, Wolfram, 2302 Johnson, Jeffrey J., 2081 Transy, Catherine, 2407 Chalkley, Roger, 2390 Ozato, Keiko, 2041 Trus, Michael, 2418 Chalupny, Jan, 1853 Johnson, Kyle, 1891 Chan, Edward K. L., 2164 Jones, Steven W., 2413 Pace, T., 2423 Chen, Xiaorong, 2111 Park, Eun-Chung, 2081 Ciafre, Silvia-Anna, 2437 Kallestad, Jeffery, 1882 Parker, Roy, 2269 Kanbe, Toshio, 2214 Paulson, K. Eric, 1841 Van Ness, Brian G., 1950 Clarke, Catherine F., 2315 Varmuza, Sue, 2335 Clarke, Louise, 1863 Kaplan, David R., 2359 Phi-Van, Loc, 2302 Kato, Jun-ya, 2407 Picci, L., 2423 Vilcek, Jan, 1982 Clayton, David A., 2191 von Kries, Jens P., 2302 Cohen, Hannah, 2418 Kato, Kazuto, 2017 Pickett, Cecil B., 1841 Collins, Steven J., 2154 Kavathas, Paula, 1853 Platt, Frances M., 1901 Coutts, Margaret, 2060 Kedes, Larry, 2402 Plowman, Gregory D., 1969 Cumsky, Michael G., 1873 Kessin, Richard H., 1921 Podgorski, Gregory J., 1921 Kim, Yeong S., 1940 Pollard, K. Michael, 2164 Wada, Yoh, 2214 Dancis, Andrew, 2294 Kimmel, Alan R., 2367 Ponzi, M., 2423 Wakamatsu, Yoshio, 2017 Darnell, James E., Jr., 1841 Kiss, Ibolya, 2432 Presutti, Carlo, 2437 Webster, Keith A., 2402 Deagostini-Bazin, Hermine, Kitamoto, Katsuhiko, 2214 Protic, Miroslava, 2041 Weil, P. Anthony, 2390 1959 Klausner, Richard K., 2294 Pyper, Joanna M., 2035 Wells, Gerald B., 2176 Deak, Ferenc, 2432 Kolb, Janet M., 2049 Whitney, J. Andrew, 1853 Dean, Ann, 2247 Kolodziej, Peter A., 1915 Quinton, Tina J., 1891 Williams, Lewis T., 2359 Della Seta, Flavio, 2437 Kondoh, Hisato, 2017 Wissinger, Bernd, 2428 DePinho, Ronald, 2096 Korsmeyer, Stanley J., 1901 Rajagopalan, Malini, 1940 Wittekind, Michael, 2049 Dickson, Robert C., 2176 Koski, Raymond A., 1931 Reed, Randall R., 2237 Woychik, Nancy, 1915 Disteche, Christine M., 1969 Kramer, James M., 2081 Reinherz, Ellis L., 2407 Dodd, Jonathan, 2049 Krowczynska, Anna, 2060 Remacha, Miguel, 2182 Dore, E., 2423 Kutsunai, Sally Y., 2315 Reshef, Lea, 2418 Driscoll, Suzanne E., 2104 Rhee, Sue Goo, 2359 Yamagishi, Masahiro, 2049 Duigou, Gregory J., 2027 Lamb, Robert A., 1989 Robertson, Kent A., 2154 You, Kwang H., 1940 Dunn, Teresa M., 2308 Lee, Byeong J., 1940 Roeder, G. Shirleen, 2379 Young, Richard A., 1908, Lee, David C., 2111 Roeder, Robert G., 2145 1915 Edwards, Peter A., 2315 Lee, Gene W., 1982 Rogers, Kathleen T., 2111 Yoza, Barbara K., 2145 Engebrecht, JoAnne, 2379 Lee, Kyu-Ho, 2237 Rose, John K., 1853 Yu, Guo-Liang, 2070 Erikson, Eleanor, 2413 Lee, Tae H., 1982 Rossant, Janet, 2335 Erikson, R. L., 2122, 2413 Legouy, Edith, 2096 Roth, Sharon Y., 2247 Lester, Robert L., 2176 Roussel, Martine F., 2407 Farrell, Francis X., 2349 Levine, Arthur S., 2041 Rushmore, Tom, 1841 Zehner, Zendra E., 2349 Faure, Michel, 1921 Levine, Kathryn L., 1891 Ziff, Edward B., 1982 Felts, Sara J., 2390 Liao, Sha-Mei, 1915 Santoro, Bina, 2437 Zimmerman, Kathryn, 2096 Fisher, Paul B., 2027 Libermann, Towia A., 2327 Santos, Cruz, 2182 Zirngibl, Ralph, 2335