Molecular Biology of the Cell is the classic in-depth text reference in cell biology. By extracting fundamental concepts and meaning from this enormous and ever-growing field, the authors tell the story of cell biology, and create a coherent framework through which non-expert readers may approach the subject. Written in clear and concise language, and illustrated with original drawings, the book is enjoyable to read, and provides a sense of the excitement of modern biology. Molecular Biology of the Cell not only sets forth the current understanding of cell biology (updated as of Fall 2001), but also explores the intriguing implications and possibilities of that which remains unknown.

The hallmark features of previous editions continue in the Fourth Edition. The book is designed with a clean and open, single-column layout. The art program maintains a completely consistent format and style, and includes over 1,600 photographs, electron micrographs, and original drawings by the authors. Clear and concise concept headings introduce each section. Every chapter contains extensive references. Most important, every chapter had been subjected to a rigorous, collaborative revision process where, in addition to incorporating comments from expert reviewers, each co-author reads and reviews the other authors' prose. The result is a truly integrated work with a single authorial voice.

Garland
Vice President: Denise Schanck
Managing Editor: Sarah Gibbs
Senior Editorial Assistant: Kirsten Jenner
Managing Production Editor: Emma Hunt
Proofreader and Layout: Emma Hunt 
Production Assistant: Angela Bennett
Text Editors: Marjorie Singer Anderson and Betsy Dilernia
Copy Editor: Bruce Goatly
Word Processors: Fran Dependahl, Misty Landers and Carol Winter 
Designer: Blink Studio, London 
Illustrator: Nigel Orme 
Indexer: Janine Ross and Sherry Granum
Manufacturing: Nigel Eyre and Marion Morrow

Bruce Alberts received his Ph.D. from Harvard University and is 
President of the National Academy of Sciences and Professor of 
Biochemistry and Biophysics at the University of California, San 
Francisco. Alexander Johnson received his Ph.D. from Harvard 
University and is a Professor of Microbiology and Immunology at
the University of California, San Francisco. Julian Lewis received
his D.Phil. from the University of Oxford and is a Principal 
Scientist at the Imperial Cancer Research Fund, London.
Martin Raff received his M.D. from McGill University and is at the 
Medical Research Council Laboratory for Molecular Cell Biology 
and Cell Biology Unit and in the Biology Department at University 
College London. Keith Roberts received his Ph.D. from the 
University of Cambridge and is Associate Research Director at the
John Innes Centre, Norwich. Peter Walter received his Ph.D. from 
The Rockefeller University in New York and is Professor and 
Chairman of the Department of Biochemistry and Biophysics at
 the University of California, San Francisco, and an Investigator of 
the Howard Hughes Medical Institute.

© 2002 by Bruce Alberts, Alexander Johnson, Julian Lewis, 
Martin Raff, Keith Roberts, and Peter Walter.
© 1983, 1989, 1994 by Bruce Alberts, Dennis Bray, Julian Lewis, 
Martin Raff, Keith Roberts, and James D. Watson.

All rights reserved. No part of this book covered by the copyright 
hereon may be reproduced or used in any format in any form or 
by any meansgraphic, electronic, or mechanical, including 
photocopying, recording, taping, or information storage and 
retrieval systemswithout permission of the publisher.

Library of Congress Cataloging-in-Publication Data
Molecular biology of the cell / Bruce Alberts . . . [et al.].-- 4th ed. 
   p. cm 
   Includes bibliographical references and index.
   ISBN 0-8153-3218-1 (hardbound) -- ISBN 0-8153-4072-9 (pbk.) 
   1. Cytology. 2. Molecular biology. I. Alberts, Bruce.
   [DNLM: 1. Cells. 2. Molecular Biology. ] 
QH581.2 .M64 2002 
571.6--dc21

							2001054471 CIP

Published by Garland Science, a member of the Taylor & Francis Group, 
29 West 35th Street, New York, NY 10001-2299

Printed in the United States of America

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Cell Biology Interactive
Artistic and Scientific Direction: Peter Walter 
Narrated by: Julie Theriot
Production, Design, and Development: Mike Morales





Front cover Human Genome: Reprinted by permission
from Nature, International Human Genome Sequencing 
Consortium, 409:860921, 2001 © Macmillan Magazines
Ltd. Adapted from an image by Francis Collins, NHGRI; 
Jim Kent, UCSC; Ewan Birney, EBI; and Darryl Leja, 
NHGRI; showing a portion of Chromosome 1 from the
initial sequencing of the human genome.


Back cover In 1967, the British artist Peter Blake created
a design classic. Nearly 35 years later Nigel Orme 
(illustrator), Richard Denyer (photographer), and the 
authors have together produced an affectionate tribute 
to Mr Blake's image. With its gallery of icons and 
influences, its assembly created almost as much 
complexity, intrigue and mystery as the original. 
Drosophila, Arabidopsis, Dolly and the assembled 
company tempt you to dip inside where, as in the 
original, "a splendid time is guaranteed for all." 
(Gunter Blobel, courtesy of The Rockefeller University; Marie 
Curie, Keystone Press Agency Inc; Darwin bust, by permission 
of the President and Council of the Royal Society; Rosalind 
Franklin, courtesy of Cold Spring Harbor Laboratory Archives; 
Dorothy Hodgkin, © The Nobel Foundation, 1964; James Joyce, 
etching by Peter Blake; Robert Johnson, photo booth 
self-portrait early 1930s, © 1986 Delta Haze Corporation all 
rights reserved, used by permission; Albert L. Lehninger, 
(unidentified photographer) courtesy of The Alan Mason 
Chesney Medical Archives of The Johns Hopkins Medical 
Institutions; Linus Pauling, from Ava Helen and Linus Pauling 
Papers, Special Collections, Oregon State University; Nicholas 
Poussin, courtesy of ArtToday.com; Barbara McClintock, 
© David Micklos, 1983; Andrei Sakharov, courtesy of Elena 
Bonner; Frederick Sanger, © The Nobel Foundation, 1958.)