Chapter8Thefutureofcellresearch
Thewholecellissiderablymorethahewparts。Thesamealsobesaidaboutthegeheidentifioftheblueprintforindividualmolepohedertakeionthatarigorouscharacterizationofallofthepartsseparatelywillleadtofthewhole。Thisisasystemofiioionism,whichhasbeenadominantphilosophyinbiologivestigationfordecades。However,justtoidentifythemolecularpartsofthepuzzleisnotgoingtotellushoorksifwedoherulesfortheirassembly。Thisrequiresthedevelopmentofapproavestigate‘systemsbiology’or‘bioplexity’,asaparadigmshift(i。e。‘thinkihebox’)inbiologicalresearch,whereinthegeistouhecolleteraultiplemolecularprootonlywithiself,butalsoatthetissue,an,andahebottomlihemoleculesdrivethecelltodrivetheanism,ordaheditsmolereality,suterasliesomewherebetweenthecellrespondingtoitsimmediatee,balathetrolsofgeneexpression。
Therearemaingareasofreseartoeiandingofhowcellularbehaviourgesodramaticallyaftersubtlegesatthelevelofgenesaherapproachesusecellstocureadisease,forextraetals,thebreakdowroleumproducts,httoproducebiofuels。Equallyfasgareoureffortstothetiduhebiologybehihischapterwebrieflyexamihesefuturediredhowtheymightevolve。
Systemsbiology
thepleteDNAsequeafewhumans。idlyinguandingofthebiochemiismsiheday-to-dayexistehedhowitdividesaes。Ienyears,advanmolecularteologyhaveallowedustoinduitesinthousaheirapanyingRNAsignals,andproteinprodu。Thesegeseasuredmoreorlessatthesametimeahiheknowledgeingoutofthisofteologieshasdevelopedintoitsow,knownassystemsbiology。Ithasallowedustoseemillioleiiohedifferehecell。Earlyexperimentsmohegesthatocaitissubjectedtoaknowicaldrug。Forexample,icase,adrugihitstargeteeinandst。arentnhourabilitytoahousandsofindividualgeheirproductssimultaneouslyisthatadrugalsesinthelevelsofmaeins,oftenseeminglyuheienzyme,whichmaybeincreasedorreduatdifferihismayaedrugsideeffectsbutalsoallowsthedevelopmentof‘er’morespecificpharmaceuticals。Byfurtherapplyihodologytovariousbiologicalsystems,wearestartingtodiscoverthealterationsingeneexpressionandproteiakeplagvariousbiologicalprocessessuchascelldivisionaioheseexperimeakerelativelylittletimetoperfwhattheymeanwilltakelohevastamountofdatageoiunately,analysisofthisinformationhasbeenmadepossiblebypowerfulputing。Ingly,dmyreliesonthis insilicobiology,whiownasbioinformatics,tosolvethedifficultquestionsofbiologicalbehaviourintermsofDNAandproteinsequence。
LeroyHood,apiohisfield,suggestedabeautifulexampleofhowsystemsbiologymightworkiieheirdery,givingapinprickofblood。Whatfollowsisthefullbiochemie,andproteinanalysisofthebody’sfundhealthstate。Thisinformatiolyputedforallpossiblediseases,matchedwiththesymptoms,andtherapiesorfurthertestssuggestedallinamatterofmihisispersonalizedmedie,adreamafewyearsago,andnowonlyamatterof(uime。cerresearchersarealreadyusieinandDNAteoremelysmallnumberofcercellsthatbefoundinthebloodofapatientsufferingfromasolidtumour(asmallumourcellsareuouslyshedintotheblood,passingthroughthecapillariessupplyihegrowingtumour)。Pharmaceuticalresearchersareusihodstoihegeneraleffiewanticerdrugs。
&hedynamiatureoftheliviofollowthefateofindividualprbiologicalprocesses(forinstangstemcelldifferentiatioheabilitytotagoeinsahemiime。Previously,moleculessuchasgreeprotein(GFP)wouldbeusedaslabelsbutthistaganytimeslargerthanthemoleterest,andpossiblyisnormalactivity。Taggingisnowpossiblewithminuteinaumdots)whiall(seeFigure1)thattheypassstraightthroughthecellmembraeologyisthestrollingmatteronanatomiolecularsdieraaterialsbetween1and100raeroftwohemassiveadvantageatthisscaleistheultrafastspeedofthereas,whichareremihosefouhisgrowingareaofreseargappliedtolivihemolealysisofdisease。Futureappliswillihemianipulationoffaultygenes,buildingcellularbio-sensors,aingDNAputers。Imagiimewhenanoralmediotjustachalkypill,butwillsistofacapsulefullofnanrammedtofitheDNAofcerahreateningvirus。patientswithaeddiseasecouldbecorredaffescouldberestructuredbysurgiorobots。
Syiclife
AlllivingcellsarerelatedtoeachotherbytheiruseofthesamegeidasmallnumberofhighlyservedproteihissuggeststhatallmodernlifeevlearallivihepoheAbases,aminoadevensmallpolymersofthese—havebeehelabresoftheextremechemidphysiditioedasthehcooleddointheeraeheticentalprecursors。
eedtocreateoleculesbeforetheydivide,buttheyalsowareandalltheplexproteinsynthesismaerytogetthere。Therefore,themisforacellare:agstructure;aDNAsequeinthelenes,eagforaproteinthatplechemicalreaostimportayttheseprocessestogetherwiththeinformationtotlyreplicateitself。Fatmoleself-assembleintoprimitivemembranes,fsphericalstructurestoprotetratetheirts。Artifiescapableofassistingihesis,andfunalsynthesizedgerodutocellslaucleushavebeeedsuccessfullyiilycreatedaphotosyigalltheeovert98%ofsunlightintosugar。Thesebioteologyapplistlymimiaturallifeprocesses。illbeabletorecreateapleteilifeformislessbutsuayhelpustofurtherdefilifeis。
Growinglimbsandears
Inourowheliverisitedregeion,butboffastarfishorasalamaoihemnalsthatareusedbythesespeciesteelimbsinadultlife。Mammalsseemtoohissignallingpathwaydurihoftheearlyembryobutitisapathwaythatmayotentialtobereactivated。Follicalremoval,thewingsgrowbaembryoheproduofaproteiisswit。Freionalsotakeplacelaterinthelifewntproteiadpoleshavethisabilitybutitisnormallylostwheamorphoseints。Theexpressionofroteinaroundaninjuryisthoughttocauseareprortraionofmaturecellscapablethecelltypeshelimb。Veryyounghavebeenknrertips,andsuingpossibilitiesforhumantissueregeion。
&erence
weliveforever?Insteadold,the‘immortaljellyfish’(Turritopsisnutricula)reachessexualmaturity,thesbacktoitsjuveage(equivalenttoembryonicmaturejellyfish(medusastage),thebellsurfaddigestivealaraedintopolypswhidevelopintomaturejellyfishandsoon。Thispropertyofbypassihbyreversingitslifecycleis,sofar,uheanimalkingdom,allowingasolejellyfishtoliveandreproduitely。Fortuofthesejellyfish(theybreedevery24hours)arelosttothegeneralhazardsinthesea。
&udieshaveshownthataninsuliorproteiansplaysavitalroleinglifespan。Thisgeneisimportaiiooleraahelackofoxygen,aack。Mutationsinthisgehewormtolivetwig(albeitinlaboratorys)。Higherlevelsofaproteinthattrolstheexpressionofthisiorarealsocorrelatedwithlohewormleadsthewaytoexamiheequivalentgenesinmammalsareabletlife。Asweuahowcellsage,itmaybepossibletomahegeidmeicsofthisprocess。
Aivewayofgainingimmortalityistocreateaeofyourself。ThefirstmammaledwasDollythesheepbywayofsomatiusfer(introduucleusofaoailizedeggfollowedbysurrogatemotherhood)。Thishasledtotheprodueof‘immortal’alsingbelovedhouseholdpets。Theproblemwithproduewaiallyfromanadulthatitiheriskoftheearlyoofage-relateddiseasesingdthegrowthoftheearlyembryonicbodyhasbeeedasanewacellsourcetoprovidetherapeuticstemcellsfortransplahidpolitishavestoppedfurtherworkihemoment。
&hisplaisbasedonthegle-celledlifeformslikebacteria,yeasts,andalgaehaveevolvedovermanymilliooulticellularanimalscapable(inourownsituatitouandhowlifeitselfworks。Meticulousobservationandprofoundthinkingby19th-turybiologistshelpedustouandwhatthecellis,howeverynewcellisrelatedtoitsmothercellthroughitsgenes,andhowonecellorofevolveintonewspeciesbyadaptingtoageuheiuralsele。The20thturyhasseentheunravellingofthepohedegofthevastamountsofinformationthatliesinDNAandproteins,andaninitialgraspoftheunibetweehemoleposihe21stturywillprobablyyieldwaysofusiuralorsyocuredisease,regeofthebody,aendlifespan。Perhapswecreatecell-basedsuperputers。JustastheevolvingbaEarth’searlyhistedthechemistryofthebiosphere,similarapproachescouldbeusedtoreversetheharmwehavedoneinourgexploitationandpollutio。peure,livingsomeformorother,arelikelytosurviveandadapttotheireherhumaoseethisisratherless。