Nucleic Acids Research Executive editors R.T.Walker, Birmingham, UK B.E.Griffin, London, UK P.Pearson, Baltimore, MD, USA R.J.Roberts, Cold Spring Harbor, R.B.Hallick, Tucson, AZ, USA J.M.Rosen, Houston, TX, USA NY, USA J.E.Hearst, Berkeley, CA, USA I.C .Eperon, Leicester, UK N.C.Martin, Louisville, KY, USA M.J.Gait, Cambridge, UK W.R.McClure, Pittsburgh, PA, USA Editorial board M.Beato, Marburg, FRG W.T.Garrard, Dallas, 7X, USA S.E.V.Phillips, Leeds, UK A.J.Berk, Los Angeles, CA, USA F.Giannelli, London, UK R.H.Reeder, Seattle, WA, USA A.P.Bird, Edinburgh, UK P.J.Hagerman, Denver, CO, USA C.W.Schmid, Davis, CA, USA J.L.Bos, Utrecht, The Netherlands C.Helene, Paris, France Y.Shimura, Kyoto, Japan H.Buc, Paris, France A.J.Jeffreys, Leicester, UK R.Simpson, Bethesda, MD, USA K.Calame, New York, NY, USA C.J.Leaver, Oxford, UK D.Soll, New Haven, CT, USA N.Chua, New York, NY, USA H.Lehrach, London, UK B. Sollner-Webb, Baltimore, MD, USA D.A.Clayton, Stanford, CA, USA D.M.J.Lilley, Dundee, UK S.Spadari, Pavia, Italy A.Das, Farmington, CT, USA T.Lindahl, London, UK R.H.Symons, Adelaide, Australia M.L. DePamphilis, Nutley, NJ, USA S.M.Linn, Berkeley, CA, USA H.F.Tabak, Amsterdam, The M.P.Deutscher, Farmington, CT, USA J.T.Lis, Ithaca, NY, USA Netherlands J.E.Donelson, Iowa City, IA, USA R.McMacken, Baltimore, MD, USA S.Tilghman, Princeton, NJ, USA F.Eckstein, Gottingen, FRG D.A.Melton, Cambridge, MA, USA I.Tinoco, Jr, Berkeley, CA, USA J.D.Engel, Evanston, IL, USA J.R.Nevins, Durham, NC, USA Y.Wang, Shanghai, China P.T.Englund, Baltimore, MD, USA S.Nishimura, Tokyo, Japan D.J.Weatherall, Oxford, UK D.J.Finnegan, Edinburgh, UK E.Ohtsuka, Sapporo, Japan A.M.Weiner, New Haven, CT, USA H.Fukuhara, Orsay, France M.Olson, St Louis, MO, USA G.Zon, Foster City, CA, USA D.Gallwitz, Gottingen, FRG L.Philipson, Heidelberg, FRG Editorial and Production Joy Walker, UK Editorial Office Susan Jefferies, Production Editor Carol Cook, US Editorial Office Joyce Connolly, Production Assistant Sarah Brennan, Production Assistant 0IRL atPRESS OXFORD UNIVERSITY PRESS Oxford New York Tokyo Subscriptions An annual subscription to Nucleic Acids Research comprises 24 issues plus one © IRL Press at Oxford University Press 1991. 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Author index 5811 Abe,T. 5797 Dunn,R.J. 5673 Kobayashi,Y. 5792 Adra,C.N. 5755 Ecker,D.J. 5743 Koczan,D. 5591 Akhtar,S. 5543,5551 Endo,T. 5537 Kopun,M. 5725 Alloing,G. 5525 Evans,G.A. 5796 Kreklywich,C.N. 5794 Alvarrez,V. 5806 Fang,G. 5515 Krumlauf,R. 5497 Arinami,T. 5801 Farrar,G.L. 5800 Kuhlemeier,C. 5491 Arnold,H.H. 5645 Flavell,A.J. 5533 Kumar-Singh,R. 5800 Atkins,J.F. 5607 Fodde,R. 5805 Lai,K.-M. 5763 Auld,V.J. 5673 Fortini,P. 5569 Landfear,S. 5787 Azorin,F. 5639 Fox,R. 5795 Lane,S. 5793 Backendorf,C. 5633 Franze,A. 5561 Lavedan,C. 5804 Bagley,R. 5802 Fregeau,C.J. 5583 Le Blancq,S.M. 5790 Basu,S. 5551 Freier,S.M. 5743 Leclair,B. 5755 Beggs,J.D. 5483 Froguel,P. 5799 Lench,N.J. 5796 Belt,P.B.G.M. 5633 Fuchs,P.P. 5603 Lesage,S. 5799 Bentley,D.R. 5803 Gardner,E. 5795 Leupin,W. 5507 Bernard,L.E. 5794 Gecz,J. 5806 Liu,Q. 5703 Bernardi,G. 5561 Gesteland,R.F. 5607 L6pez-Larrea,C. 5806 Best-Belpomme,M. 5689 Geyer,C.K. 5799 Lovell-Badge,R. 5497 Bignami,M. 5569 Ghahraman,P. 5788 Lucas,A.M. 5802 Bleackley,R.C. 5583 Gonzalez,C. 5743 Ma,C. 5749 Bobrow,M. 5803 Griffiths,D.E. 5791 Macaya,G. 5561 Bonfanti,M. 5739 Grimaldi,G. 5661 MacDonald,M.H. 5575 Braun,T. 5645 Gupta,S.K. 5673 Manzini,G. 5625 Braus,H. 5785 Hagamuchi,H. 5801 Maraia,R.J. 5695 Breakfield,X.O. 5798 Hanson,S. 5787 Marino,M. 5661 Breukel,C. 5804,5805 Hardesty,B. 5749 Martinez-Balbas,M.A. 5639 Brieley,C. 5533 Hayakawa,H. 5597 Martinez-Naves,E. 5806 Broggini,M. 5739 Herman,B. 5543 Marzluff,W.F. 5653 Broom,A.D. 5719 Hickson,I.D. 5519 Matassi,G. 5561 Bryant,L.A. 5533 Hill,J. 5791 Mathew,C.G. 5803 Byrne,J. 5795 Hobom,G. 5591 Matsui,Y. 5763 Callen,D.F. 5793 Hoeijmakers,J.H.J. 5633 Matsuura,S. 5792 Carpenter,S. 5796 Hofmann,S. 5491 McBumey,M.W. 5755 Carrera,P. 5639 Hogan,B.L.M. 5763 McElligott,D.L. 5796 Cech,T.R. 5515 Hoke,G.D. 5743 Mejean,V. 5525 Cera,C. 5707 Holman,K. 5793 Melis,R. 5561 Chan,S.-K. 5681 Hopwood,J.J. 5796 Mentink,M.M. 5800 Chazin,W.J. 5507 Horn,G.T. 5798 Merril,C.R. 5797 Chen,D. 5703 Hotaling,E. 5713 Miyamura,T. 5792 Chen,L.Z. 5793 Humphries,P. 5800 Moerman,D.G. 5669 Chen,X. 5703 Hunt,A.G. 5575 Mogen,B.D. 5575 Chen,Y. 5703 Hutchison III,C.A. 5731 Morris,C.P. 5796 Chollet,A. 5507 Iba,H. 5537 Motomiya,M. 5797 Christopherson,M.S. 5719 Ishizawa,M. 5792 Mulligan,L.M. 5795 Claverys,J.-P. 5525 Jardine,K. 5755 Nakamura,Y. 5804 Cohen,D. 5799 Jones,D.G.L. 5785 Napierski,I. 5725 Condron,B.G. 5607 Jordan,A.S. 5800 Nelson,P.V. 5796 Content,J. 5789 Jost,J.-P. 5771 Nishina,H. 5537 D'Incalci,M. 5739 Juliano,R.L. 5543,5551 Nowell,P.C. 5799 Davies,C.J. 5731 Junien,C. 5804 Ochmachi,T. 5797 de Mendonca Lima,L. 5789 Karran,P. 5569 Odijk,H. 5633 Deaven,L. 5804 Kase,R.S. 5790 Oetting,W.S. 5800 Degrave,W. 5789 Kennedy,J.L. 5801 Okuno,H. 5537 Devedjian,J.-C. 5525 Khan,P.M. 5805 Oliva,R. 5786 Dogliotti,E. 5569 Kidd,K.K. 5801 Owttrim,G.W. 5491 Donald,K.A.I.G. 5791 Kiff,J.E. 5669 Ozelius,L. 5798 Dowdy,S.F. 5763 Kikuchi,H. 5797 Paillard,S. 5619 Draper,K. 5743 King,M.W. 5777 Paker,N. 5795 Driver,V,B, 5743 King,R.A. 5800 Palumbo,M. 5707 Dubois,J. 5802 Kitayama,K. 5801 Pandey,N.B. 5653 Instructions to Authors Please read these instructions carefully and follow them strictly to ensure that Computer papers will only be considered if they describe new applications or the review and publication of your paper is as efficient as possible. Please note novel algorithms relevant to nucleic acid sequence detenmination or analysis. Small that on submission all manuscripts must be accompanied by a manuscript submittal improvements in existing programs of variations of well-established algorithms form, a copy of which can be found at the end of these instructions. will generally not be suitable. Manuscripts dealing with computer analysis of already published sequences SCOPE OF THE JOURNAL are acceptable only if new and interesting findings emerge. Nucleic Acids research provides rapid publication for papers on physical, chemical, For The Record biochemical and biological aspects of nucleic acids, their constituents and proteins Several areas of research are suitable for presentation in this section. with which they interact. In addition, a section entitled Nucleotide Sequence Update (1) Sequence data: This is limited to the description of sequences of genes whose publishes recent database entries available on the EMBL File Server. products are relevant to nucleic acid metabolism and interactions. Structure RNAs and their genes are appropriate.