
In many respects, we understand the structure of the universe better than the
workings of living cells. Scientists can calculate the age of the Sun and predict
when it will cease to shine, but we cannot explain how it is that a human being
may live for eighty years but a mouse for only two. We know the complete
genomes equenceso f thesea nd many other speciesb, ut we still cannot predict
how a cell will behave if we mutate a previously unstudied gene. Stars may be
l0a3 times bigger, but cells are more complex, more intricately structured, and
more astonishing products of the laws of physics and chemistry. Through heredity
and natural selection, operating from the beginnings of life on Earth to the
presentd ay-that is, for about 20Voo f the ageo f the universe-living cellsh ave
been progressively refining and extending their molecular machinery and
recording the results of their experiments in the genetic instructions they pass
on to their progeny.
With each edition of this book, we marvel at the new information that cell
biologists have gathered in just a few years. But we are even more amazed and
daunted at the sophistication of the mechanisms that we encounter. The deeper
we probe into the cell, the more we reafize how much remains to be understood.
In the days of our innocence, working on the first edition, we hailed the identification
of a single protein-a signal receptol say-as a great step forward' Now
we appreciate that each protein is generally part of a complexwith many others,
working together as a system, regulating one another's activities in subtle ways,
and held in specific positions by binding to scaffold proteins that give the chemical
factory a definite spatial structure. Genome sequencing has given us virtually
complete molecular parts-lists for many different organisms; genetics and
biochemistry have told us a great deal about what those parts are capable of
individually and which ones interact with which others; but we have only the
most primitive grasp of the dynamics of these biochemical systems, with all
their interlocking control loops. Therefore, although there are great achievements
to report, cell biologistsf ace eveng reaterc hallengesf or the future.
In this edition, we have included new material on many topics, ranging from
epigeneticsh, istonem odificationss, mall RNAs,a nd comparativeg enomicst,o
geneticn oise,c ytoskeletadl lmamics,c ell-cyclec ontrol, apoptosis,s tem cells,
and novel cancer therapies. As in previous editions, we have tried above all to
give readers a conceptual framework for the mass of information that we now
have about cells. This means going beyond the recitation of facts. The goal is to
learn how to put the facts to use-to reason, to predict, and to control the
behavior of living systems.
To help readers on the way to an active understanding, we have for the first
time incorporatede nd-of-chapterp roblems,w ritten by Iohn Wilson and Tim
Hunt. These emphasize a quantitative approach and the art of reasoning from
experiments. A companion volume, Molecular Biology of the CelI, Fifth Edition:
TheP roblemsB ook0 SBN9 78-0-8153-4110-9b)y, t he samea uthors,g ivesc omplete
answerst o thesep roblemsa nd alsoc ontainsm ore than 1700a dditional
problems and solutions.
A further major adjunct to the main book is the attached Media DVD-ROM
disc. This provides hundreds of movies and animations, including manythat are
new in this edition, showing cells and cellular processesin action and bringing
the text to life; the disc also now includes all the figures and tables from the main
book,p re-loadedin to PowerPoint@pr esentationsO. thera ncillariesa vailablefo r
the book include a bank of test questions and lecture outlines, available to qualified
instructors,a nd a seto f 200f ull-coloro verheadtr ansparencies.
Perhaps the biggest change is in the physical structure of the book. In an
effort to make the standard Student Edition somewhat more portable, we are
providing chapters 2r-25, covering multicellular systems, in electronic (pDF)
form on the accompanying disc, while retaining in the printed volume chapters
l-20, covering the core of the usual cell biology curriculum. But we should
emphasize that the final chapters have been revised and updated as thoroughly
as the rest of the book and we sincerely hope that they will be read! A Reference
Edition (ISBN9 7s-0-8153-4r11-6c)o, ntainingt he full seto f chaptersa sp rinred
pages, is also available for those who prefer it.
Full details of the conventions adopted in the book are given in the Note to
the Readert hat follows this PrefaceA. s explainedt here,w e have taken a drastic
approach in confronting the different rules for the writing of gene names in different
species: throughout this book, we use the same style, regardless of
speciesa, nd often in defianceo fthe usuals pecies-specifcico nventions.
As always,w e are indebted to many people. Full acknowledgmentsfo r scientific
help are given separatelyb, ut we must here singleo ut somee xceptionally
important contributions: Iulie Theriot is almost entirely responsible for chapters
16 (cytoskeleton)a nd 24 (PathogensI,n fection, and Innate Immunity), and
David Morgan likewise for chapter 17 (cell cycle). wallace Marshall and Laura
Attardi provided substantialh elp with chapters 8 and 20, respectively,a s did
Maynardo lson for the genomicss ectiono f chapter4 ,X iaodongwangf or chapter
18, and Nicholas Harberd for the plant section of Chapter 15.
we also owe a huge debt to the staff of Garland science and others who
helped convert writers' efforts into a polished final product. Denise schanck
directed the whole enterprise and shepherded the wayward authors along the
road with wisdom, skill, and kindness. Nigel orme put the artwork into its final
form and supervisedt he visuala spectso f the book,i ncluding the backc over,w ith
his usual flair. Matthew Mcclements designed the book and its front cover.
Emma Jeffcockla id out its pagesw ith extraordinarys peeda nd unflappablee fficiency,
d ealingi mpeccablywith innumerablec orrections.M ichaelM oralesm anaged
the transformation of a mass of animations, video clips, and other materials