Nalane ea Nts'etsopele ea Biology ea Sejoale-joale ea Limolek'hule
Baeloji ea limolek'hule ea sejoale-joale ke lekala la saense le ithutang lits'ebetso tsa bophelo boemong ba limolek'hule—haholo-holo DNA, RNA le liprotheine, hammoho le mekhoa e laolang tlhahiso ea liphatsa tsa lefutso le lefa. Thuto ena e bile motheo oa tsoelo-pele e ngata ea saense le theknoloji, ho tloha tlhahlobong ea mafu a thehiloeng liphatsa tsa lefutso ho ea boenjiniere ba lintho tse phelang bakeng sa lijo le meriana. Nts'etsopele ea eona ha ea ka ea etsahala ka tšohanyetso, empa ho e-na le hoo ka letoto la lintho tse sibollotsoeng tse matlafatsang, lipuisano le boqapi ba tekheniki ho tloha qetellong ea lekholo la bo19 la lilemo ho isa mehleng ea hona joale ea genomics le baeloji ea maiketsetso.
Metso ea nalane: ho tloha liseleng ho ea limolek'huleng
Pele lentsoe "biology ea limolek'hule" le qaptjoa, biology e ne e se e fetile phetohong ka khopolo-taba ea sele (Schleiden le Schwann) le khopolo-taba ea ho iphetola ha lintho (Darwin). Leha ho le joalo, potso e kholo e ile ea sala: motheo oa lefa la litšobotsi ke ofe? Qetellong ea lekholo la bo19 la lilemo, Gregor Mendel o ile a theha melao ea lefa ka liteko tsa lierekisi. Qalong lintho tseo Mendel a li fumaneng ha lia ka tsa eloa hloko hakaalo, empa ea e-ba motheo oa liphatsa tsa lefutso ha li "sibolloa hape" mathoasong a lekholo la bo20 la lilemo.
Hoo e ka bang ka nako e tšoanang, bo-rasaense ba ile ba qala ho hlahloba sebopeho sa lisele ka botlalo. Ho sibolloa ha li-chromosome le ho hlokomeloa ha karohano ea sele (mitosis le meiosis) ho ile ha lebisa khopolo-taba ea hore li-unit tsa lefa li lula li-chromosome. Thomas Hunt Morgan le sehlopha sa hae ba bontšitse kamano ea liphatsa tsa lefutso le li-chromosome ka lithuto tsa ntsintsi ea litholoana Drosophila melanogaster. Sena se tiisitse hore liphatsa tsa lefutso li na le sebaka sa 'mele, empa ha sea ka sa araba potso ea tlhaho ea tsona ea lik'hemik'hale: na liphatsa tsa lefutso li entsoe ka liprotheine kapa li-nucleic acid?
DNA e le thepa ea liphatsa tsa lefutso: ntoa ea ho fumana bopaki
Mathoasong a lekholo la bo20 la lilemo, bo-rasaense ba bangata ba ne ba nka liprotheine e le tsona tse ka sehloohong bakeng sa lintho tse amanang le liphatsa tsa lefutso ka lebaka la ho rarahana ha tsona. DNA e ne e nkoa e le bonolo haholo. Phetoho e kholo e qalile ha Frederick Griffith (1928) a sibolla ketsahalo ea "phetoho" libaktheriang tsa Streptococcus pneumoniae: libaktheria tse seng kotsi li ka fetoha kotsi ka mor'a ho pepesehela lintho tse tsoang libaktheriang tse kotsi tse shoeleng. Leha ho le joalo, Griffith o ne a e-so tsebe moemeli oa phetoho.
Katleho e tlile ka liteko tsa Avery, MacLeod, le McCarty (1944), tse bontšitseng hore ntho e fetolang ke DNA. Leha ho ntse ho phehisanoa khang, bopaki bo ile ba matlafala ka mor'a liteko tsa Hershey le Chase (1952) tse sebelisang bacteriophages: ke DNA ea vaerase feela e ileng ea kena liseleng tsa baktheria 'me ea jara tlhahisoleseling ho theha livaerase tse ncha. Kahoo, DNA e ile ea amoheloa e le thepa ea liphatsa tsa lefutso.
Sebopeho sa DNA le tsoalo ea paradigm e ncha
Ho lemoha hore DNA ke thepa ea liphatsa tsa lefutso ho hlahisitse potso e latelang: DNA e boloka le ho kopitsa tlhahisoleseling joang? Karabo e tsotehang e hlahile ka 1953 ha James Watson le Francis Crick ba hlahisa mohlala oa double helix oa DNA. Ba sebelisitse data ea diffraction ea X-ray ho tsoa ho Rosalind Franklin le Maurice Wilkins. Sebopeho sa double helix, se nang le lipara tsa sona tse tlatsanang tsa motheo (A-T le G-C), se hlalositse mokhoa oa ho pheta-pheta: thapo ka 'ngoe e ka sebetsa e le mohlala oa thapo e ncha.
Tšibollo ena ha ea araba potso ea hore na DNA e ikopitsa joang, empa hape e thehile motheo oa tsoalo ea baeloji ea limolek'hule e le thuto ea sejoale-joale. "Tlhahisoleseding ea baeloji" joale e ka utloisisoa e le tatellano ea metheo ea naetrojene e ka futsoang le ho fetoleloa mosebetsing oa sele.
Thuto ea motheo le kutloisiso ea phallo ea tlhahisoleseling ea liphatsa tsa lefutso
Lilemong tsa bo-1950 le bo-1960, khopolo ea phallo ea tlhahisoleseling ea liphatsa tsa lefutso e ile ea qaptjoa ho seo se ileng sa tsejoa e le "thuto ea mantlha": DNA e fetisetsoa ho RNA, ebe e fetoleloa ho ba protheine. Leha mekhelo (e kang phetolelo e ka morao ho li-retrovirus) e se e ananetsoe, thuto ena e fana ka kakaretso e pharaletseng ea kamoo liphatsa tsa lefutso li laolang litšobotsi tsa sebopuoa.
Ho sibolloa ha mRNA ho ile ha hlakisa hore RNA e sebetsa e le mokena-lipakeng pakeng tsa DNA le liprotheine. Ka mor'a moo, bo-rasaense ba ile ba qhaqha khoutu ea liphatsa tsa lefutso—melao e hokahanyang li-triplets tsa motheo (li-codon) le li-amino acid. Marshall Nirenberg, Har Gobind Khorana, le basebetsi-'moho le bona ba bontšitse kamoo tatellano ea li-nucleotide e khethollang tatellano ea li-amino acid liprotheineng. Sena se entse hore kamano pakeng tsa liphatsa tsa lefutso le lihlahisoa tsa tsona tse sebetsang e be e tiileng le e ka lekoang ka liteko.
Phetoho ea enzyme le theknoloji ea DNA e kopantsoeng hape
Tsoelo-pele baelojing ea limolek'hule e nolofalitsoe haholo ke ho sibolloa ha lisebelisoa tsa "limolek'hule", haholo-holo lienzyme. Lienzyme tsa thibelo - "lisekere" tse khaolang DNA ka tatellano e itseng - li butse tsela bakeng sa tsamaiso e nepahetseng ea DNA. Hammoho le ligase tsa DNA, tse ka "kopanyang" likaroloana tsa DNA, bo-rasaense lilemong tsa bo-1970 ba ile ba hlahisa theknoloji ea DNA e kopantsoeng hape: ho kopanya DNA ho tsoa mehloling e fapaneng le ho e kenya linthong tse phelang tse kang libaktheria bakeng sa ho holisa kapa ho hlahisa.
Ho hlaha ha boenjiniere ba liphatsa tsa lefutso ho bile le tšusumetso e kholo saenseng le indastering. Tlhahiso ea insulin ea batho ho sebelisoa libaktheria tse kopantsoeng e bile mohlala oa pele, o ileng oa fetola kalafo ea lefu la tsoekere. Leha ho le joalo, phetohelo ena e boetse ea baka lipuisano mabapi le boitšoaro le polokeho ea likokoana-hloko. Seboka sa Asilomar (1975) se tšoaile ntlha ea bohlokoa ho theheng litataiso tsa lipatlisiso tsa DNA tse kopantsoeng, se bontšang kamoo saense ea sejoale-joale e fetohang hammoho le melaoana le boikarabello ba sechaba.
Mekhoa ea ho latellana le ho tlola ho ea mehleng ea genome
Mohato o latelang e ne e le ho bala tatellano ea DNA ka kotloloho. Mafelong a bo-1970, Frederick Sanger o ile a qapa mokhoa oa ho latellana ha DNA o neng o tla fetoha tekanyetso ka mashome a lilemo. Ka bokhoni ba ho bala tatellano ea liphatsa tsa lefutso, baeloji ea limolek'hule e ile ea tloha ho utloisiseng mekhoa feela ho ea ho khona ho etsa 'mapa oa tlhahisoleseling ea liphatsa tsa lefutso ka botlalo.
Lilemo tsa bo-1980 li tlisitse boqapi bo fetolang papali: PCR (polymerase chain reaction), e qapiloeng ke Kary Mullis. PCR e entse hore ho khonehe ho eketsa palo e kholo ea likaroloana tsa DNA ka potlako, ka theko e tlase, le ha bonolo. Theknoloji ena e potlakisitse hoo e ka bang sebaka se seng le se seng sa baeloji ea limolek'hule—ho tloha lipatlisisong tsa motheo le bo-forensiki ho ea ho ho fumanoa ha mafu a tšoaetsanoang.
Sehlohlolo sa litabatabelo tsa mehla ea genome e ne e le Human Genome Project (1990–2003), projeke ea machaba e ileng ea atleha ho etsa 'mapa oa genome ea motho. Katleho ena e tšoaile phetoho ea paradigm: ho tloha ho ithuteng liphatsa tsa lefutso tse le 'ngoe ho ea ho ithuteng liphatsa tsa lefutso tse felletseng, marang-rang a liphatsa tsa lefutso le phapang ea liphatsa tsa lefutso tsa baahi.
Post-genome: taolo ea liphatsa tsa lefutso, epigenetics, le RNA e sa ngoleng khoutu
Ka mora hore genome ea motho e baloe, potso ea motheo e ile ea fetoha: haeba palo ea liphatsa tsa lefutso tsa motho e se holimo kamoo ho neng ho lebelletsoe, ho rarahana ha lintho tse phelang ho hlaha joang? Tlhokomelo e ile ea fetela taolong ea liphatsa tsa lefutso—neng, hokae, le hore na liphatsa tsa lefutso li hlahisoa ka matla hakae. Lipatlisiso li hlwaile karolo ea bohlokoa bakeng sa likarolo tsa taolo, lintlha tsa mongolo, le sebopeho sa chromatin.
Epigenetics e ntse e hola ka potlako e le tšimo e ithutang liphetoho tlhahisong ea liphatsa tsa lefutso ntle le ho fetola tatellano ea DNA, mohlala ka methylation ea DNA le liphetoho tsa histone. Ho feta moo, ho sibolloa ha li-RNA tse sa ngoleng khoutu tse kang miRNA le lncRNA ho senotse hore RNA ha se feela mokena-lipakeng empa hape ke molaoli oa bohlokoa oa lits'ebetso tse fapaneng tsa sele. Kutloisiso ena e ntlafatsa thuto ea mantlha 'me e fana ka maikutlo a hore phallo ea tlhahisoleseling ea liphatsa tsa lefutso e fetoha haholo.
Nako ea ho hlophisa liphatsa tsa lefutso le baeloji ea maiketsetso
Lilemong tse leshome tse fetileng, ho hlophisoa ha liphatsa tsa lefutso ho bile le phetoho e kholo ka lebaka la CRISPR-Cas9. Theknoloji ena e lumella DNA ho khaoloa libakeng tse lakatsehang ho sebelisoa RNA e le tataiso, e leng se lumellang liphetoho tsa liphatsa tsa lefutso ho etsoa kapele le ka theko e tlase ha ho bapisoa le mekhoa e fetileng. CRISPR e potlakisitse lipatlisiso mabapi le ts'ebetso ea liphatsa tsa lefutso, nts'etsopele ea lijalo tse hanelang mafu, esita le kalafo ea liphatsa tsa lefutso ea liteko.
Ka nako e ts'oanang, baeloji ea maiketsetso e hlahile e le mokhoa o sa "hlophiseng" feela empa hape o rala litsamaiso tse ncha tsa baeloji. Bo-rasaense ba qalile ho haha lipotoloho tsa liphatsa tsa lefutso joalo ka ho kopanya likarolo tsa elektroniki: li-promoter, liphatsa tsa lefutso le balaoli li ile tsa hlophisoa ho hlahisa mekhoa e itseng liseleng. Lipakane li ne li tloha ho hlahiseng biofuel le thepa e sireletsang tikoloho ho isa ho mekhoa ea phekolo ea kankere e thehiloeng liseleng.
Qeto: baeloji ea limolek'hule e le motheo oa bokamoso
Histori ea baeloji ea limolek'hule ea sejoale-joale ke pale ea kamoo potso e bonolo—motheo oa lefa ke ofe?—e ileng ea fetoha kutloisiso e tebileng ea mekhoa ea bophelo boemong ba eona ba motheo ka ho fetisisa. Ho tloha litekong tsa phetoho ea baktheria, ho ea ho sibolloeng ha DNA double helix, ho ea ho petsoheng ha khoutu ea liphatsa tsa lefutso, ho ea ho tatellano, PCR, le mahlale a CRISPR, ketsahalo e 'ngoe le e 'ngoe ea bohlokoa e ile ea bula monyako oa tsoelo-pele e eketsehileng.
Nakong e tlang, baeloji ea limolek'hule e tla hokahana haholoanyane le bioinformatics, bohlale ba maiketsetso, le mahlale a sele e le 'ngoe a khonang ho etsa 'mapa oa lits'ebetso tsa baeloji ka tharollo e ikhethang. Ka nako e ts'oanang, liphephetso tsa boitšoaro - lekunutu la data ea liphatsa tsa lefutso, polokeho ea baeloji ea baeloji, le phihlello e lekanang ea mekhoa ea phekolo e thehiloeng liphatsa tsa lefutso - li tla tsoela pele ho re tšoenya. Ho utloisisa nalane ea eona ho re lumella ho bona hore baeloji ea limolek'hule ha se pokello ea mekhoa feela, empa ke e 'ngoe ea lintho tse kholo ka ho fetisisa tse finyeletsoeng ke batho ka ho bala, ho toloka, le, ho isa bohōleng bo itseng, ho ngola bocha puo ea bophelo.
