підручники. біохімія / Uchebnik_po_Biokhimii_E_S_Severin

5'

Hp-

A T

T A

3' 5'

l

5' 3'

A T

T A

A T

T A

3' 5'

Penll111Ka4111~

3'

-CH3

A T

T A

H3C-

-CH3

JJeorn:noB -GGGITA-, Ha3bIBaeMbIX TeJJoMepHOH IlOCJJe,UOBaTeJihHOCTblO, HJIH npocTO TeJIOMepHOH

.UHK. HaJJ111111e TeJJoMep tteo6xon11Mo )l)UI 3aBeprnettmi: penJJHKaUHH KOHUeBbIX HHcpopMaTHBHblX nocJJe,UoBaTeJJbHOCTeil xpoMocoM, T.e. )],JUI coxpatteHIDI retteTWieCKOH HHcpopMaUHH.

IlocJJe 3aBeprneHHSI perrJJHKaUHH xpoMOCOMbl 5'-KOHUbl .uoqepHHX uerreit .UHK tte,UOCTPOeHbl, TaK KaK rrocJJe y.uaJJeHIDI rrpaiiMepoB 3TH cpparMeHThI OKa3hIBalOTCSI He,UopellJIHUHPOBaHHbIMH. 3To npo-

HCXOL(HT IlOTOMy, 'ITO,ll,HK-rroJJHMepa3a ~. OTBeqa10w.a51 3a 3anoJ1ttett11e 6pern11, o6pa3oBatttto:H: nocJJe yn:aJJeHH51 npatl:Mepa, He MO)K.eT BeCTH CHHTe3 uerr11 .UHK OT 3'- K 5'-KOHUY(p11c.

TaKHM o6pa30M, B xon:e Ka)K.,lloro UHKJia pe11JI11Kau1111 5'-KOHUblCHHTe3HpoBaHHblX uerreit YKOpaqnBalOTC51. Ho TaKHe n0Tep11 He npen:cTaBJI51IOT onacHOCTH )],JUI retteTH'leCKOHHHcpopMaUHH xpoMOCOM, nornMy 'ITOYKOPO'Iett11e,ll,HK H,UeT 3a cqfa TeJJoMep. Bo BpeM51 cJJen:yrow.ero UHKJia pe11JIHKauww

5'-KOHI..1,bl u.erreii .IlHK OITHTb oeraIOTeH He)J,OeTpoeHHblMH. TaKHM o6pa30M, e KIDK.llhIM KJieToqHbIM )J,eJieHHeM ,IlHK xpoMoeoM 6y.zzyr rroeJie,lJ,OBaTeJibHO YKOpaqttBaTbeH. YKopoqeHHe TeJioMep B 6oJihllIHHerne KJieTOK no Mepe HX erapeHHH - BIDK-

HblH <t>aKTop, orrpe,ll,eJIHIOlllHH rrpO,ll,OJDKHTeJibHOeTb )KH3HH opraHH3Ma.

0)1,HaKo B 3M6pHOHaJibHbIX H JlPYrHX 6bieTpo- )J,eJIHrn:HxeH KJieTKax ITOTepH KOHI..1,0B xpoMoeoM He- ,lJ,OrryeTHMbl, ITOTOMY q'foYKOpoqeHHe ,IlHK 6y,lJ,eT rrpoHexo,lJ,HTb oqeHh 6h1eTpo. B 3YKaPHOTHqeeKHX KJieTKax HMeeTeH <t>epMeHT TeJIOMepa3a (HYKJieOTH,lJ,HJITpaHe<t>epa3a), 06eerreqHBa10rn:Hi1 soeeTaHOBJieHHe He,ll,operrJIHI..1,HpOBaHHbIX 5'-KOHI..l,OB. K oeo6eHHoernM 3Toro <t>epMeHra OTHoeHT rrp11eyTeTBHe B KaqeeTBe rrpoeTeTHqeeKOH rpyITITbl PHK. Cl>parMeHT PHK B aKTHBHOM 1..1,eHTpe TenoMepa3bI eJiy)KHT MaTpH1..1,ei1 rrpH eHHTe3e TeJIOMepHbIX ITOBTOpOB XpOMOeOM.

C rroMOlllhIO PHK <t>epMeHT KOMTIJieMeHrapHo rrpHKpeTIJIHeTeH K 3'- KOHU.Y He)J,oerpoeHHOH )J,0- qepHeH u.errH ,IlHK. TenoMepa3a no rrpHHU.Hrry KoMrrJieMeHTapHoeTH rroene,lJ,oBaTeJibHO y,lJ,JIHHHeT 3'-KOHel..I,1..1,err11 ,IlHK Ha 0)1,HH reKeaHYKJieOTH,ll, -GGGTTA-. CHHTe3 seer,ll,a H,ll,i::T OT 5'-K 3'-KoH- u.y. 3areM reJI0Mepa3a eMern:aeTeH no u.errH )];HK Ha 0)1,HH reJIOMep H HaqHHaeT eHHTe3 HOBOfO ¢>parMeHTa -GGGTTA- (pHe. 4-19, I>).

B 60JibIIIHHCTBe eoMaTttqeeKHX KJieTOK TenoMepa3a HeaKTHBHa, TaK KaK eoMaTttqecKaH KJieTKa HMeer ,lJ,JIHtty TeJIOMepHOH .IlHK, )J,OeTaTOqttylO ,lJ,JIH BpeMeHH )KH3HH KJieTKH H ee IlOTOMeTBa. 0)1,HaKO He60Jib- llIYIO aKTHBHOCTb TeJIOMepa3bl o6Hapy;KHBaIOT B KJieT-

KaX e BbleOKOH eKopoeTblO o6HOBJieHHH, TaKHX KaK

JIHM<t>ou.HThl, eTBOJIOBbie KJieTKH Koernoro M03fa, KJieTKH 311HTeJIHH, 311H,l1,epMHea KO)KH H ,ll,p.

,II;. K.JIETOqffblH QHKJI II EfO PEI'YJUIQHJI

Ilpou.eeehl poera H ,lJ,eJieHHH KJieToK Jie)l(aT B oeHOBe )KH3HH n106oro oprattH3Ma. Ho rrpe)l(,Jle qeM eosepruHTb ,lJ,eJieHHe, KJieTKa )J,OJI)l(Ha e BbieOKOH roqHOeTbIO KOITHpOBaTb eBOH reHOM, eHHTe3HpoBaTb MHO)l(eerno BbieOKO- H HH3KOMOJieKYJIHPHblX eoe,ll,HHeHHH. CoBOKYJIHOeTb eo6hITHi1, 06eeneqHsa10rn:HX )J,eJieHHe 3YKaPHOTHqeeKHX KJieTOK, Ha3blBaIOT «KJieTOlfHbIH UHKJI». IlpO,ll,OJDKHTeJibHOeTb KJieroqHoro 1..1,HKJia 3aBHeHT OT THrra )J,eJIHlllHXeH KJieTOK, y B3poenoro qeJIOBeKa OHa MO)l(eT sapbHposaTb rrpHMepHO OT 8 q H 6onee, a ,lJ,JIH HeKOTOpbIX THITOB KJieTOK )J,0 rona H 60Jibllle (pHe. 4-20).

Bee ¢>a3bI KJieroqHoro U.HKJia GP S, G 2, M MOryr pa3JilfqaTbCH no JlJIHTeJihHOeTH, HO B oeo6eHHOeTH 3TO KaeaeTeH ¢>a3bI G 1, JlJIHTeJihHOeTb KoTopoii MO)l(eT 6hITb paBHa npaKTHqeeKH ttyJIIO HJIH 6bITb eTOJib npO,ll,OJI)KHTeJibHOH, qTO MO)l(eT Ka3aTb- eH, 6yJlTO KJieTKH soo6rn:e npeKpaTHJIH ,ll,enem1e. B 3TOM enyqae rosopHT, qTo KJieTKH HaxO,lJ,HTeH B eoeTOHHHH ITOKOH (¢>a3a Go). TaK, HeiipOHbl B3poeJI0f0 qeJioBeKa He ,ll,eJIHTeH B006rn:e. KJieTKH 311HreJIHH KHlIIeqHHKa )J,eJIHTeH Ha rrpOTH)l(eHHH Beeii )KH3HH qeJIOBeKa, HO ,lJ,IDKe y 3THX 6bieTporrpOJIH- <t>epHpYIQrn:HX KJieTOK 110,lJ,fOTOBKa K )J,eJieHHIO 3aHHMaer 24 q, KJierKH nerKHx, rroqeK, rreqeHH so B3poeJIOM opraHH3Me HaqHHaIOT )J,eJIHTbeH TOJibKO

JIHlllb B OTBeT Ha ITOBpe)l(,JleHHe opraHOB. BHeillHHe eHfHaJibl MOryr eTHMYJIHPOBaTb HJIH

HHrH6HpOBaTb npoxo)l(,JleHHe KJieTKH qepe3 1..1,HKJI. IlponH<t>epaTHBHbie eHmaJihI oqeHb pa3Hoo6pa3HhI, OHM 3aBHeHT OT THrra KJieTKH, eTa,ll,HH pa3BHTHH H ,ll,pyrHx <t>aKropoB. TaKHMH eHrHanaMH MOryr 6hITb <t>aKTOpbl poera, HHTepJieHKHHbl, ropMOHbl, enoeo6Hbie 110,lJ,Jlep)l(HBaTb HJIH HHJlyUHpoBaTb rrpOJIH<t>epa1..1,HIO onpe,ll,eJieHHblX THITOB KJieToK. CHrHaJihHhle MOJieKyJihI eBH3hIBaIOTeH erreu.H<t>lfqeeKHMH MeM6paHHblMH peu.enTOpaMH, aKTHBHPYIOT BHyTPHKJieTOqHbie IlyTH rrepe,ll,aqH eHfHaJIOB OT peu.errTopa K HJlPY H TaKHM o6pa30M HHJlYU.HPYlOT rpaHeKpHITI..l,HIO onpe,ll,eJieHHbIX reHOB. 0)1,HHMH H3 rrepBbIX aKTHBHPYIOTeH reHbl, KO,lJ,HPYIOlllHe 6eJIKH UHKJIHHbl. oeJIKH 6bIJIH Ha3BaHbl 1..1,HKJIHHaMH, ITOTOMY qTo HX KOHI..l,eHTpa- 1..1,HH B KJieTKe nepHO)J,HqeeKH MeHHeTeH 110 Mepe npoxo)l(,JleHHH KJieTKOH pa3HbIX <t>a3 KJieTOqHoro 1..1,HKJia.

Bee U.HKJIHHbI ,lJ,eJIHr Ha 2 no,lJ,eeMeH:erna: G1-

UHKJIHHbI (0, E) H MHTOTlfqeeKHe 1..1,HKJIHHbl (A H B). JI106oi1 H3 U.HKJIHHOB npe,ll,eraBJieH rpynnoii rroJIHMop¢>HbIX 6eJIKOB, HarrpHMep 1..1,HKJIHH 0 rrpe,ll,- eTaBJieH <t>opMaMH 01, 02, 03. Y KIDK,ll,oro THna 1..1,HKJIHHOB eeTb fOMOJIOflfqHblH yqaeTOK H3 100 aMHHOKHeJIOTHblX oeTaTKOB - «1..1,HKJIHHOBblH 6oKe», orneqaIOrn:HH 3a eBH3bIBaHHe e I..l,HKJIHH3aBHeHMOH KHHa3oi1 (or aHrn. CDK -

B KJieTKax 3yKapttOTOB eyrn:eernyer npHMepHo soeeMb pa3JIHqHbIX COK (CDKl-8), aKTHBHPYIOlllHXeH pa3JilfqHbIMH U.HKJIHHaMH (ra6JI. 4-2).

UttKJIHH3aBHeHMbie KHHa3bI, eBH3blBaH U.HKJIHH, nepexo)J,51T B aKTHBttylO <l>OPMY H MOryr <t>oe<t>opHJIHpOBaTb erreu.tt<t>lfqeeKHe 6enKH, ttarrpttMep <t>aKrophI TpaHeKpHITI..l,HH, 6eJIKH-HHfH6HTOpbl <t>aKTo-

pOB TpaHCKP11DUH11, KOTOpbie peryJrnpyIOT Cl1HTe3 ¢epMeHTOB, 06ecne1.rnsa10w11x pemrnKau1110. C11HTe3 K<UK,ll,OfO Ul1KJ111Ha Ha'-IHHaeTCHnp11 00)1,fOTOBKe K COOTBeTCTBYIOWeH ¢a3e KJieTO'-IHOro U11KJia, ero KOHUeHTpawrn B KJieTKe flOBbIWaeTCH, a nocJie OKOH'IaHHH ¢a3bI pe3KO nMaeT no HYJIH. 3asepw11sw11e CBOIO pa6oTy KOMnJieKCbl UHKJll1HOB 11 CDK CBH3bIBaIOTCH cneu11¢11'-lecKl1MH6eJIKaM11, HHrn611pyIOWHMl1 HX aKTl1BHOCTb, 11 3aTeM 00)1,- BepraIOTC51 pa3pyweHl1IO.

Ill. PEnAPAL.tlllSI

Ilpouecc, 003BOJI51IOWl1H )!(HBbIM opraHl13MaM BOCCTaHaBJIHBaTb nospe)!()1,eHH51, B03Hl1Ka10w11e B D.H K, Ha3bIBaIOT penapau11et1. Bee penapau110HHbre MexaH113Mbl OCHOBaHbl Ha TOM, '-ITOLI.HK - nsyxueno'-!e'-!HaHMOJieKyJia, T.e. B KJieTKe ecTb 2

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PMC. Cl>83bl 1<11eT04HOro 4MK118. nocne cjla3bl M, B XOAe

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A. CnoHTAHHhIE noBPE)K)J,EHlUI

HapyweHH51 KOMm1eMeHTapHocTH uenetr LI.HK

MOfYT npo11CXO)J,l1Tb cnOHTaHHO, T.e. 6e3 yqaCTH51

KaK11x-111160 nospe)l{)1.a10w11x ¢aKTopos, HanpttMep

B peJyJihTaTe onm6oK peIIJIHKaU,HH, neJaMHHHpOBaHlffi ttyKJieOTHJJ:OB, nenypttmnau,11tt.

0wH6KH peDJIHKaIUIH

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Tiptt HenpaBHJibHOM cnapttBaHHH B nepBHqHoH CTPYKTYPe .uoqepHeH uenH ,[I.HK He06hNHhie ocHOBaHHSI He nOSIBJISIIOTCSI, HapYllleHa TOJibKO KOMIIJieMeHTapHOCTb. CttcTeMa penapautt11 HeKOMIIJieMemapHhIX nap ,UOJDKHa npOHCXO)lHTb TOJibKO Ha noqepHeii: uentt H npottJBO.UHTh JaMetty HeKoMnneMemapHhIX OCHOBaHHH TOJibKO B Hett. <l>epMeHThl, yqaCTBYIOlllHe B y.uaneHHH HenpaBHJibHOH napbl HyKJieOTH)l,OB, pacn03HaIOT MaTpHqHyIO uenb no HaJIHqHIO MeTHJIHpOBaHHbIX OCTaTKOB a,n:eHHHa B nocJie)lOBaTeJibHOCTSIX -GATC-. TioKa OCHOBaHHSI ttyKJieOTH)l,HbIX OCTaTKOB B ,n:oqepHeH uentt HeMeTHJIHPOBaHbl, Q:>epMeHThl )l,OJDKHbl ycneTb BblSIBHTb OlllHfiKY peIIJIHKall,HH H ycTpaHITTb ee.

Pacno3HaBaH11e n y.uaneHtte (nepBbiii: 3Tarr) HeKOMIIJieMeHTapHoro ttyKJieOTH)l,a npOHCXO)l,SIT npn yqacTHH cneuttanhHhIX 6eJIKOB mut S, mut L, mut H. Ka.x<..n:hrn H3 6eJIKoB BhIIIOJIIDieT cBoIO cneUHQ:>uqecKYIQ Q:>yHKUHIO. Mut S Haxo,UHT HenpaBIDihHYIO napy H CBSI3hrnaeTcSI c 3THM Q:>parMeHTOM. Mut H npttcoe.uttIDieTCSI K MeTHJIHPOBattHOMY (no an:e- HHHY) yqaCTKY -GATC-, pacnoJIO)KeHHOMY B6JIH3H HeKOMIIJieMeHTapHoii: napbI. CBH3yI01llHM Me)K)l,y mut S H mut H CJIY)KHT 6eJioK mut L, ero npttcoe-

.UttHeHtte JaBeplllaeT o6pa3oBaHHe aKTHBHoro Q:>epMema. <l>opMttpoBaHtte KOMIIJieKca mut S, mut L, mut H Ha yqacTKe, conep)Kalll,eM onrn6KY, cnoco6crnyeT npoSIBJieHHIO y 6enKa mut H 3H)l,OttyKJieaJHOH aKTHBHOCTH. <l>epMeHTaTHBHhlH KOMIIJieKC rn.u-

pOJIHJyeT Q:>oc¢03¢ttptty10 CBSl3b B HeMeTHJIHPOBaHHOH uentt (pttc. 4-21).

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,UenypHHH3alUfSI (anypHHH3alUfSI)

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.ueJOKCHpl16030H (pttc. 4-22).

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site).

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,Ue3aMHHuposauue

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B penapauim npttHHMaeT yqacT11e

K03HJJa3a, fl1,UpOJil13YI01llaSI CBSl3ll Me)K)ly aHOMaJibHbIM OCHOBaHHeM H )l,e30KCI1ptt6030H (nepBbIH :Jrnn), B peJyJihTaTe o6paJyeTcSI ATI -caiiT, KOTOPhIH pacrroJHafa Q:>epMeHT AIJ-3u.uonyKJ1ea- 3a (BTOpoii: 3Tan). KaK TOJlbKO B uen11 ,[I.HK B03HMKaeT pa3pbIB, B pa6oTy BCTynaeT elll,e O,U11H

¢epMeHT - Ail-3K30HyKJiea3a, KOTOpbrti oTwenJrneT OT uern1 11.e30KC11p11603y, Jl!1WeHHYIO OCHOBaHl151 (TpeT11tl 3Tan). B uen11 Ll,HK noHBJrneTcH 6pewb pa3MepoM B omrn HyKJJeon111.. C11e11.y10w11t\ ¢epMeHT Ll,HK-noJIUMepa3a ~ K 3'-KOH UY pa3opBaHHOH uen11 np11coe11.11H5IeT HYKJieOTl1il no np11Hwrny KOMnJleMeHTapHOCTl-1 ('1ernepTblK3Tal1). lfro-

6bI coe11.11Hl1Tb LI.Ba CB060Jl.HblX KOHUa (3' -KOHeu BCTpOeHHOfO HyKJJeOTl1Jl.a 11 5'-KOHeu OCHOBHOH uen11), Tpe6yeTCH ewe 011.11H ¢epMeHT - ,UHK- Jiura3a (nHTbitl 3rnn).

Hepenap11pyeMo 11 no3TOMy onacHo 11.eJaMHHHpouaH11e MeTl1Jil1pOBaHHOfO Ul1T0311Ha. npo,UyKT ero cnOHTaHHOro 11.e3aMHHHpouaHHH - Tl1Ml1H'

I

0

I

O=P-0-CH

I 2

0-

Uenb ,QHK

P111c. 4-22. Aenyp111H111aa1..1111si - cnoHTaHHoe yA11J1eH111e BA8HMHa 111n111 ryaHMHa.

AnypHHHa111poeaHHa~

neHToaa

I

0

I

o~h--o-~

Uenb ,QHK

0

HOpMaJihHOe ;:i:mr )],HK OCHOBam1e, KOTOpoe He pacn03HaeTCH L(HK-N-rJTMK03I1Jla30H.

B. llH,IJ,YU,HPYEMhlE IIOBPE)l{)J,EHHH

Htt;:i:yuttpyeMbie noBpe)l(J];emrn B03HMKaIOT B L(H K B pe3yJihTaTe B03;:i:etlcTBwH pa3ttoo6pa3HhIX MYTareHHhIX ct>aKTopoB KaK pauttauttottttotl:, TaK H XMMWieCKOH npttpO;:J:hl.

06pa30BaHHe ,uHMepoB DHpmBWlllOBblX OCHOBaHHH

Ilo;:i: ;:i:etl:crntteM YcDO .llBOHHaH CBH3h Me)J()ly C5 M C6 aTOMaMM yrnepo;:i:a B COCTaBe nttpHMll)lMHOBhIX OCHOBaHMH (TMMMHe M UMT0311He) MO)((eT pa3pblBaTbCH. ATOMhl yrnepo;:i:a OCTalOTCH CBH3aHHhIMH o;:i:ttotl: CBH3hIO. PaccTOHHtte Me)J()ly rrapaJIJieJihHhIMM ITJIOCKOCTHMM OCHOBaHMH ITOJIMHYKJieOTll)lHOH uerrtt, B KOTOPhIX npoH3oIUeJI pa3phrn, paBHO rrpttMeptto 3,4 A. 3TO paccTOHHtte IT03BOAAeT ocBo6o- ;:J:HBWHMCH BaJieHTHocrnM Me)l(J];y C-C aTOMaMtt rrnpMMM;:J:HHOBhfX OCHOBaHHH, pacnOJIO)((eHHhIX rrocJie;:J:OBaTeJibHO B uerm .[(HK, c¢>opMttpOBaTb UMKJio6yTaHOBOe KOJihUO (pwc. 4-25). B 3aBHCMMocrn OT Toro, KaK11e OCHOBaHMH coe;:i:1-rneHbl B ;:J:HMep, MX Ha3hlBaIOT ;:J:MMepaMM TMMMHa, UHT03ttHa MJIM TH- MMH-UMT0311HOBhIMM ;:J:ttMepaMM.

y ;:i:anetttte ITMpMMtt;:i:ttHOBhIX ;:J:ttMepoB rrpottCXO;:i:MT no;:i: ;:i:etl:crnMeM <J>zyrO.JIHa3bl. cDepMeHT pacmerurneT BHOBh o6pa30BaBIUtteCH CBH3H Me)J()ly coce;:i:HttMH ITHpMMtt;:i:MHOBhIMM OCHOBaHMHMH H BOCCTaHaBJIHBaeT HaTttBHYIO CTPYKTYPY· B ¢>oTOJIMa3e eCTh yqacTOK, Jitt6o caM nornoma10mtttl: cl:>OTOHhI (B nrne:tt L£acTtt crreKTpa), Jitt6o CBH3bIBaJOlUMHCH c KO$aKTopaMtt, aucop611py10m11M11 cBeT. TaKMM o6pa3oM, cBeT aKTHBttpyeT ¢>oTOJitta3y, KOTOpaH pacn03Hafa ;:J:HMepbl B 06JIYlfeHHOH )],HK, npttcoe;:i:HHHeTCH K HMM 11 pa3pbrnaeT B03HHKlUMe Me)J()ly nttpttMH;:i:HHOBhlMH KOJih-

T"1M"1Hbl

-G-C-T-C-A-T-C-C- -C-G-A-G-T-A-G-G-

Hp ~ CnoHTaHHoe

NH3 1 .1:1eaaM111H111poeaH111e

-G-C-T-U-A-T-C-C- -C-G-A-G-T-A-G-G-

~p~ AHK-N-rm1Koa111naaa

-G-C-T----A-T-C-C- -C-G-A-G-T-A-G-G-

Hp~ An-aH.QOHyKilea3a p,-p1116oaa 1

-G-C-T A-T-C-C- -C-G-A-G-T-A-G-G-

ALIT<l>>,l ,QHK-nom1Mepa3a ~

-G-C-T-C-A-T-C-C- -C-G-A-G-T-A-G-G-

AT<I> .,1,QHK-n111raaa

-G-C-T-C-A-T-C-C- -C-G-A-G-T-A-G-G

PMc. 4-24. Penapa1.1Msi An-cai4Toe c y"l&CTMeM .QHK-N-rnMK0- 3Mn&3b1 .... An-3K30HYKl1ea3bl.

uaMM CBH3H. IloCJie 3TOro ¢>epMeHT OT)leJIHeTCH OT

)],HK.

1Ioepe1K;leHHH OCHOBaHHH .IJ:HK XHMlflleCKHMH

MYfarenaMH

A30TMCTbie OCHOBaHMH B .[(HK MOryr ITO)lBepraThCH

pa3Hoo6pa3HhIM rroBpe)J()leHMHM: aJIKMJ1ttpoBam110,

T111M"1HOBb1i.1 .Q"1Mep

OKHCJiemuo, BOCCTaHOBJiemno IDIH CB5I3hIBaHIUO ocHOBaHH5l c ¢opMaMM,UHhIMH rpymrnpoBKaMH. Perrapau,1151 tta•mttaeTCH c rrp11:coe11,11:HeHH5l LJ:HK-N- fJIHK03IDia3hI K rroBpe)K,ll,eHHOMy octtoBattmo. CywecrnyeT MHO)l(eCTBO LJ:HK-N-rJIHK03HJia3, crrel.l,H- ¢H'IHbIXK pa3HbIM M0M¢HUHPOBaHHhIM OCHOBaHH5IM. <l>epMeHTbl fMPOJIHTHqecKH pacweIIJI5IIOT N-rJIHK03H.JlHYIO cBmh Me)K,ll,y HJMetteHHhIM octtoBaHHeM H ,ll,e30KCHpH6030M, 3TO IIPHBO.Il,HT K o6pa30BaHHIO AII-cai1Ta B u,enH LJ:HK (rrepBhIM Tiarr).

Perrapal.1,H51 AIT-caitrn MO)l(eT rrpo11:cxo.Il,HTh HJIH TOJTbKO IIPH yqaCTHH LJ:HK-HHcepTa3bl, KOTOPlliI rrp11:coe-

.Il,HH5leT K .Il,e30KCHpH603e OCHOBaHHe B COOTBeTCTBHH c rrpaBIDIOM KOMIIJieMeHTaPHOCTH, HJlH rrpH yqacTHH Bcero KOMIIJieKca ¢epMeHTOB, yqaCTBYIOil.l,HX B perrapau,HH: Ail-3H.Il,OHYKJTea3hI, Ail-3K30ttyKJTea3hI, LJ:HK-noJTHMepa3hI ~ H LJ:HK-JIHraJhl.

B. ,I(E<I>EKThl PEIIAPAI.JJIOHHhIX CMCTEM

M HACJIE,11,CTBEHHhIE liOJIE3HM

IlurMe1rruas1 KceponepMa

y 60JihHblX B CHCTeMe perrapal.l,HH CHIDKeHa aKTHBHOCTb ¢epMeHTOB, OTBeTcTBeHHblX 3a Y.Il.aJieHHe HerrpaBHJibHblX OCHOBaHHll, «3aCTpOMKY» 6pe- llIH H .Il,pyme <PYHKUHH. LJ:e¢eKT perrapal.l,HOHHOM CHCTeMbl IIP05IBJI51eTC5l B CBepxqYBCTBHTeJTbHOCTH K Y<l>-cBeTY, qTo rrpttBO.Il.HT K IIOHBJieHttIO KpacHbIX INTeH Ha KO.JK.e, nepeXO.Il,5llll,HX B He3IDKHBaIOWHe KOpOCTbl H Hepe.Il,KO B paK KO)l(H.

TpHXOTHOnHCTJ>OcllHB

3a6oJieBaHHe CB5I3aHO c IIOBbillleHHOH ¢oToqYBCTBHTeJibHOCTblO LJ:HK, Bbl3BaHHOH CHH)KeHtteM aKTttBHOCTH ¢epMeHTa, yqacrny10wero B Y.Il.aJieHHH

.Il,ttMepoB THMttHa. CttMIITOMhI Ja6oneBaHH5l: JIOMKOCTh BOJIOC BCJie.Il,CTBHe HeXBaTKH cepbl B 6eJIKax BOJTOC H HX JIYKOBHU.; qacTO yMCTBeHHlliI H ¢tt3HqecKlliI OTCTaJTOCTh; aHOMaJTHH KO)KH H 3y60B.

Perrapal.1,H51 tteo6xo;1;mm .Il.M coxpatteHHH ttaTHBHoit CTpYKTYPhI retteTWiecKoro MaTepttana Ha rrporn- )l(eHHH BCeit )l(JfJHM oprattHJMa. CHJf)l(eHtte aKTIIBHOCTH ¢epMeHTOB penapal.l,HOHHbIX CHCTeM rrpMBO.Il,HT K HaKOIIJTeffiflO IIOBpe)K,ll,eHMM (MYTaUHM) B LJ:HK.

IlpHqHHOM MHOillX HacJie.Il,CTBeHHblX 6oJie3HeM qeJIOBeKa BbICTYnaeT HapyrneHtte OT.Il,eJibHbIX 3TaIIOB rrpou,ecca perrapau,tttt.

IV. TPAHCKP111nU111S1

TpaHCKPHIIU.H5I - rrepBaH CTa.Il.HH peanmau,tttt retteT11:qecKoi1 11:tt¢opMau,ttH B KJTeTKe. B xo.Il,e rrpo- u,ecca o6pa3yIOTrn MOJTeKyJThI MPHK, cn~amtte

MaTpttu,eH: )IJ15l CHHTe3a 6eJIKOB, a TaK)l(e TpaHCIIOPTHble, ptt60COMaJTbHbie H 11,pyrtte Bll,[(bl MOJieKYJI PHK, BhIIIOJIHHIOwtte CTpYKTYPHhie, a.Il,arrTOpHhie H KaTaJTHTJfqecKHe ¢YHKU.HH (pttc. 4-26).

AMHHOKHCflOTbl

AM11Hoa411n-1PHK

TpaHCKPMITUMH y 3yKapttoToB rrpottcxonttT B sw.pe. B ocHoBe MexaHM3Ma TJ)aHCKPMITUMM Jie)!(JfT TOT )((e CTPYKTYPHhIH rrpMHUHIT KOMTIJTeMeHTapHoro crrapttBaHMH ocHoBaHMH B MOJieKyne PHK (G=C, A=U "T=A). Ll,HK CJIY)!(JfT TOJihKO MaTpttuett Ms xone TpaHcKpttrruttM He M3MeHHeTCH. Ptt6oHYKJieo3MATpmpoc<t>aThI (UT<I>, IT<I>, AT<I>, YT<I>) - cy6cTJ)aThI M HCTO'IHHKH3HeprHH, He06XOAMMhie )]JUI npoTeKaHMSI ITOJIMMepa3HOH peaKUMM, o6pa30BaHMSI 3',5'-<t>oc<t>ontt3<l>MPHOH CBSl3M Me)J()ly PM6oHyKJie03HAMOHO<t>oc<t>aTaMM.

CttHTe3 MoneKyn PHK Ha'IttHaeTcHB orrpeneneHHhIX nocnenosaTeJihHOCTHX (caifrax) Ll,HK, KOTOphie Ha3hIBaKIT npoMOTOpbl, M 3aBepwaeTCSI B TepMMHMPYJOW.MX yqacTKax (cakrw TepMnHaUHH). YllaCTOK Ll,HK, orpaHH'IeHHhIHnpOMOTOpoM M cattroM TepMMHaUMM, npencrnBJrneT co6ott emrnttuy TpaHcKpttrrUMM - ypauc1qnnrrou. Y 3YKaPMOTOB B cocraB TJ)aHcKpttrrToHa, KaK npaBMJIO, BXOAMT OAMH reH (pttc. 4-27), y npoKapMOTOB HeCKOJihKO. B Ka)J()lOM TJ)aHcKpttrnoHe npMCYTCTByeT HettH<l>OpMaTMBHaH 30Ha; oHa conep)((l1.T cneutt<l>H'IecKHenocnenosaTeJ1hHoc- ™ ttyKJieOTHAOB, c KOTOphIMM B3aHMonettcTBYJOT peryJISITOpHhle TJ)aHCKpHITUMOHHhie <t>aKTOphI.

TpaucKpHnIU10Hb1e cj>aKTOpb1 - 6enKH, B3attMonettcrnYJOm»e c orrpeneneHHhIMM peryJISITopHhIMM catiTaMM M ycKopSIIOW.Me HJIM 3aMe)])UIIOW.Me npouecc TpaHcKpHTIUHH. CooTHorneHtte ttH<l>opMaTMBHoti M HettH<l>OpMaTMBHOH qacTeH B TJ)aHCKPMTITOHax 3yKapMOTOB COCTaBJISieT B cpenHeM 1:9 (y rrpoKapMOTOB 9:1).

CocenHtte TpaHcKpttrrTOHhI MOfYT 6hITh oTneneHhI APYf OT Apyra HeTpaHCKpM6MpyeMblMM yqaCTKaMM .[(HK. Pa3neneHMe .[(HK Ha MHO)((eCTBO TJ)aHCKpMITTOHOB IT03BOJISieT ocyw.ecTBJISITh c pa3HOH aKTMBHOCThJO MHAMBMAYMhHOe C'IMThrnamte (TpaHCKPHITUHIO) pa3HhIX reHOB.

B Ka)J()lOM TpaHCKpttrrTOHe TpaHcKptt6ttpyeTCH TOJihKO OAHa M3 AByx uenett .[(HK, KOTOpaH Ha3hIBaeTCSI MaTpwrnou, BTOpaH, KOMTIJTeMeHTapHaH ett uenh, HaJhrnaeTcH KOllHPYIOmeu. CttHTe3 uentt PHK

MAfa OT 5'- K 3'-KOHUY,rrpM 3TOM MaTpH'IHaHuerrh Ll,HK BCerna aHTMrrapanneJibHa CMHTe3MpyeMOH HYKJieMHOBOH KHCJIOTe (pttc. 4-28).

TpaHCKPMTIUHH He CBH3aHa c <t>aJaMM KJieTO':!- Horo UMKJia; OHa MO)((eT yCKOPHThCSI M 3aMe)])UIThCSI B 3aBMCMMOCTM OT l10Tpe6HOCTM KJieTKM MJIM opraHM3Ma B onpeneneHHOM 6enKe.

PHK-noJIHMepa3bI

6ttocttHTe3 PHK ocymecTBJIHeTcSI Ll,HK-3aBM- CHMhIMM PHK-rronttMepa3aMM. B sw.pax 3YKapttoTOB o6Hap~eHbI 3 crreuttaJIM3ttpoBaHHhie PHKrroJIHMepaJhI: PHK-noJinMepa3a I, CMHTe3HPYJOW.aH rrpe-pPHK; PHK-noJIHMepa3a II, orneTcTBeHHaSI 3a CMHTe3 npe-MPHK; PHK-noJIHMepa3a III, CMHTe3MPYIOW.aH rrpe-TPHK. PHK-nonttMepa3hI - OJIMfOMepHhie <t>epMeHThI, COCTOSIW.Me M3 HeCKOJihKHX cy6beAMHMU - 2a, ~, P', CT. Cy6beAMHttua CT (cMrMa) BhIITOJIHHeT peryJISITOPHYJO <l>YHKUMJO, 3TO OAMH M3 <t>aKTOpOB MHMUMaUMM TpaHCKpMITUMM. PHK-rronttMepa3hI I, II, III, Y3HaJOrn.tte pa3Hhie rrpOMOTOphl, conep)((aT pa3Hhle ITO CTpOeHMJO cy6beAHHHUhl CT.

A. CTA,rorn: TPAHCKPHTII.JJUI

B rrpouecce TJ)aHcKpMITUHM pa3.TllfllaKIT 3 CTMMM: MHMUMaUMIO, 3JIOHraUMJO M TepMHHaUMJO.

lIHHIUfaIIHJI

AKTttBaUMH npoMoTopa rrpottCXOAMT c rrOMOW.hIO 6onhrnoro 6enKa - TATA-cjJaKTopa, Ha3hIBaeMoro TaK TIOTOMy, ':!TOOH B3aMMOAeHCTByeT co crreuM- <l>ttY:eCKOH nocnenoBaTeJihHOCThJO HyKJieOTHAOB rrpOMOTOpa - TATAAA- (TATA-6oKc) (pttc. 4-29).

IlpttcoenttHeHMe TATA-<PaKTopa o6nerqaeT B3aHMonettcTBtte rrpoMOTopa c PHK-nonttMepa3olt. <l>aKTOphl MHMUMaUMM Bhl3hIBaJOT H3MeHeHHe KOH- <t>opMaUMM PHK-rronttMepa3hI M o6ecne'IttBaJOT pacKpyqMBaHMe npHMepHO OAHOro BHTKa crrnpaJIH .[(HK, T.e. 06pa3yeTCSI ypaHCK)JHIIIUIOHHaJI BHJI-