This text represents our best effort to synthesize a complex and ever-shifting field and to contribute to the broadening requirements of twenty-first-century education in molecular biology. We welcome your comments and suggestions. We thank our many colleagues whose input has helped shape this book:

Steven Ackerman, University of Massachusetts

Ravi Allada, Northwestern University

Rick Amasino, University of Wisconsin–Madison

Andrew Andres, University of Nevada, Las Vegas

Brian Ashburner, University of Toledo

Matthew Bahamonde, Farmingdale State College

Kenneth Belanger, Colgate University

Joel Belasco, NYU School of Medicine

Morgan Benowitz-Fredericks, Bucknell University

Bradford Berges, Brigham Young University

Xin Bi, University of Rochester

Robert Borgon, University of Central Florida

David Bourgaize, Whittier College

Nicole Bournias-Vardiabasis, California State University, San Bernardino

John Boyle, Mississippi State University

Jeremy Bruenn, University at Buffalo

Douglas Burks, Wilmington College

Aaron Cassill, University of Texas, San Antonio

Karl Chai, University of Central Florida

Davis Cheng, California State University, Fresno

William Cody, University of Dallas

Mary Connell, Appalachian State University

Scott Covey, University of British Columbia

Fred Cross, Rockefeller University

Cristina Cummings, Providence College

Rodney Dale, Loyola University Chicago

Susan DiBartolomeis, Millersville University

Dessislava Dimova, Rutgers University, New Brunswick

David Donze, Louisiana State University, Baton Rouge

Arri Eisen, Emory University

Danielle Ellis, California State University, Pomona

R. Paul Evans, Brigham Young University

Nicholas Ewing, California State University, Sacramento

Jason Fitzgerald, Southeastern Illinois College

Gerald Frenkel, Rutgers University, Newark

Louise Glass, University of California, Berkeley

Ann Grens, Indiana University South Bend

Theresa Grove, Valdosta State University

Nancy Guild, University of Colorado Boulder

Immo Hansen, New Mexico State University

Daniel Herman, University of Wisconsin–Eau Claire

Margaret Hollingsworth, University at Buffalo

Stan Ivey, Delaware State University

Russell Johnson, Colby College

Jason Kahn, University of Maryland

Mijung Kim, Chicago State University

Timothy Lane, University of California, Los Angeles

Curtis Loer, University of San Diego

Charles Mallery, University of Miami, College of Arts and Sciences

Kathryn McMenimen, Mount Holyoke College

Mitch McVey, Tufts University

Thomas Mennella, Bay Path College

Karl Miletti, Delaware State University

Yuko Miyamoto, Elon University

Evangelos Moudrianakis, Johns Hopkins University

Arunachalam Muthaiyan, Chicago State University

Hao Nguyen, California State University, Sacramento

Brent Nielsen, Brigham Young University

James Ntambi, University of Wisconsin–Madison

Greg Odorizzi, University of Colorado

James Olesen, Ball State University

Harold Olivey, Indiana University Northwest

Anthony Otsuka, Illinois State University

Rekha Patel, University of South Carolina

Bruce Patterson, University of Arizona, Tucson

Brian Poole, Brigham Young University

Megan Porter, University of South Dakota

Ted Powers, University of California, Davis

April Pyle, University of California, Los Angeles

Brian Ring, Valdosta State University

Herve Roy, University of Central Florida

Edmund Rucker, University of Kentucky

Ivan Sadowski, University of British Columbia

Steven Sandler, University of Massachusetts Amherst

Brian Sato, University of California, Irvine

Mary Schuler, University of Illinois Urbana-Champaign

William Scovell, Bowling Green State University

Andrei Seluanov, University of Rochester

Konstantin Severinov, Rutgers University, New Brunswick

xxviii

Xueyan Shan, Mississippi State University

Elaine Sia, University of Rochester

Ron Siu, University of California, Los Angeles, Extension

Agnes Southgate, College of Charleston

Daniel Stoebel, Harvey Mudd College

Derek Tan, Sloan-Kettering Institute for Cancer Research

Ignatius Tan, New York University

Lloyd Turniten, University of Wisconsin–Eau Claire

Jill Wildonger, University of Wisconsin–Madison

Bruce Wolff, University of Waterloo

Michael Yu, University at Buffalo

This book would not have been possible without the support of our publishers at W. H. Freeman. A book of this sort is an undertaking measured not just in hours but in sleepless nights, almost-met deadlines, conference calls, and occasional levity. It is an enterprise in which teachers sometimes become students. The needed guidance has been provided by an exceptionally talented team of editors and copy editors. Kate Ahr Parker has overseen the effort from the beginning. Few human beings are as gifted in the art of articulating urgency with grace. Anna Bristow, Erica Frost, and Lisa Samols have been our development editors. Guided by their capable hands, first-draft chapters have been created, reworked, broken up, and sometimes merged. They provided encouragement and pointed out deficiencies. They have been our partners throughout, scrutinizing every word we produced. As the project progressed, the work was honed and the chapters integrated with the help of Brook Soltvedt and Linda Strange. Both Brook and Linda are long-time veterans of the Lehninger Biochemistry series, and their expertise added immeasurably to the final product in your hands. In the end, they have managed the impressive feat of merging three voices into one. We are extraordinarily grateful to all of the editors for their dedication to this project. We are fortunate to have had the benefit of their insights and expertise.

The artwork for this book was a labor of love handled by Adam Steinberg and the artists at Dragonfly Media. Adam is also a Lehninger Principles of Biochemistry veteran, and his experience and skill are evident on almost every page of this book. He worked hand in hand with the authors to create illustrations that convey concepts concisely and in a unified style.

Our thanks also go to the consummate professionals who ensured the high quality in the production of the book: art director Diana Blume, project editor Elizabeth Geller, production coordinator Paul Rohloff, illustration coordinator Janice Donnola, photo editor Jennifer Atkins, and photo researcher Teri Stratford. We greatly appreciated their flexibility and creativity in working with complex material and ever-shifting schedules.

We express our appreciation to our colleagues, friends, and families for their patience and support.

Last, but certainly not least, we are grateful to the Moment of Discovery authors, who shared some of their favorite scientific career moments with us. Each of them provided valuable time and effort for this project and helped us add a personal touch to every chapter.

Michael M. Cox

Jennifer A. Doudna

Michael O’Donnell

December 2014