bahan-kuliah-biologi-6(1)

7/27/2019 bahan-kuliah-biologi-6(1)

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INTERAKSI ANTAR SEL-SEL

DANLINGKUNGANNYA

Biologi Selbasar

BI-100A

2005,RRE/AB,SITH ITB


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INTERAKSI ANTAR SEL-SEL DAN LINGKU1) Sel- Sel1) Sel - Matriks ekstraselular(Jaringan)



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-

Basement membrane

Basement membraneDermisSpecialized cellcell contactSpecializedcell substratum contactReticular fiber Proteoglyc an Collagen fiberCell surface receptor (integnn)

Fibroblast Elastic fiber

Dead cornified - cells

Epidermis


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Cronge incytogwle101org.anizalian

Change ri riurneohilte

ktwation 120. syinttesi

klivabccol FtfklA synItiesIS

( . 1 F i r e i f )

09!ielami

11_ \A-


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Figure 7.1 An overview of how cells are organized intotissues and how they interact with one another and withtheir extracellular environment. In this schematic diagramof a section through human skin, the cells of the epidermis

are seen to adhere to one another by specialized contacts.The basal layer of Extracollular matrixepidermal cells also adheres to an underlying, noncellular

layer (the basement membrane). The dermis consists largelyofexescellular elements that interact with each other andwith the surfaces of scattered cells. The cells containreceptors that interact with extracellular materials.


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Tlda-7-11 C4110E=L=. u Ei cm d aIF .111:12 n imi.r

Mel disoimi 5 Er uc car . Fmccion EI:M.I. pl .1

INIMACELUILLIL RECEPr011Slao =Ea= I u la r Erro 1- bi nd i ng R cod L-ca . igna 1. From 1 i Fi d-solu 1:1 EIR E rE pcoriFor NO, m=roi d

xi= or n a n6.113rp Ed. na n po6r zma Ih ar rna 6 o m ii 0- andn a kcul= &or Ei d h 13 rmon E


9/83

IZEL L S LEREACE XECUTO:1:5.11)113165:u6r '27=.' cri

Bp r rcd ch crn kol lyCD apc n or c6sc

B i rric :Fnal =cracc I u 6 dr,

=im l:D=. rco Fel rox i

rum:climb rl 7

E i rcl i nerohi Fra 1 LE. rc =FE1 r al u:u:s GIP to 13 i nd 3

tic Lr o ro

Ph pip Iv] ry imi anoF

Fraad n Lin irm

Bp ki dc h E.rmorma, ro d =Hai n th c rrcs

Chcniolly prEd Hu 1 ki p3 m. crwi . ri crn 1:rA ncion c hal nc 1r Fr nizin fa rrn inEr x = n Eral pars

FLoaym ic r E = Fix.raS 1.113 Ic-Fmx 17. r rncrn kr 3nc

protein

C-proccin-linkcd ti im n- FiC b 1 MT= 13. 3ncrox pal rr Fri:ad:I...id] cpmplanic

lindliffsic far a pramin

P MEI CAL co brrAL-r Pi' ]T11 C ELLS


10/83

Eh= ca m cria I.

Cymn pl xcrn ic co m =i a ro icrwo:n Enw il 341i n 13 i ng ph n cod 1 wal

I.=1133 od 1 in 3 dm=

Corn ri u ri od rig j . rE don 1:cmo:n plunr=11.

Sorb=

m3rlecr.

113h i jitnti

113 ri3131irr92rA 1 p rIrr i

ni or

31rmaliFidr 6 =11mcribralc

Tidy board, 1 = kp ro of,

likros prandn %de

I& nd Fy Eh c all

OrEy n = ns i s n di co: lidds=Hz Eir dic r al di di s E msc

ri s I pm= =me bu E MAi Down] ma mci. In to- na=1 i . ix 0 kwn E

no of crozdx kkon i n ko:1

Anclmring jonrdan:

"linimne =1 . copc dxr

=113. chromph onfmrirw

Ad hc rou i crudi c. r Tra ro rn:rn 1:r3nc fi b ro Ana FE ri ns *di an: "r acie

Frarcir .= cra=1 1 ul a. m3cr ix El9,1=1=1 1:1:1 n

Gap ju EEL kna S x Ersi . m crn krA nc co m CDrnouriming *Edon:allow.

Frkis cr=sdrga 'pipe F.3 migc n F rmal 1 ri n low 1

PI xcrn Eel Dm 3 b


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Endokrin Tipe penyampaian molekul sinyal


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s e l t a r g e t j a u h 4 h o r m o n

dibawa melalui pembuluh darah

parakrinMediator local -*mempengaruhi

sel target sekitar/ tetangga

dirusak oleh suatu enzimekstraselular atau diimobilisasioleh ECM

Autokrin / (contact dependent)sel responsif terhadap substansi

yang dihasilkan oleh sel itusendiri atau sel sekitarnya

Sinaptik(neuronal)Penyampaian sinyal dapat

dilakukan dengan cara proteindari suatu sel berikatan langsung


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r1.10itniro;drikl


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;en sninrgurogrona-

SDK ol p.] ix Pax. az.ds

rhy mid gland

=v-rn Id doh, 31 haa or fmins Elid.i Iva &C. or dx. xrnlno acld

p r a man d I pl 1:1 traakdown. , I n W.:4 a nd C b

MU 13 ICE sluarsc. u palkGr. p PDE-I r. cyn Mac C.. a n.:1 Ilpld niI 1s, G.-E.. In PAW o;is

Incluciz. and ma In nins. laconclaly ma Iii -mum! h srac C.1 lcEli MU 13 ICIS FN. 13 Ism 0 I 3-12f1 y r. I iypas

d al-Peal:Pea. or rho!Ina[MPor el.:. am I no ac Id gluzrnk addE.:clamp/ ric.0 11:4 ransrnh x many rid ya- musc Ego ran arr:I In o;-ninl ranctus Km

G Ice), no_roharrsml L KI 13310 31 rid W.L& s-r_axn

-Arn 47:eceijc lc a cit' ri7A.9.21)n.-ras m na IsnGlya izirrinalsCo nt.x1-4141F.k nd4cd 1).0.31p naIrE Hol4kLI KC.

picep:cilya ra_rorel wirloas odwi dayG4oF4ne op!! rypt

naightorIngc alb rn)m Ix-coming spachitaxl In E-anxi way ae- dx. Marla Ingrrarem.-mb rine pkaDln

Tab I e 1G-1 Sxn e rn p ks oF ign el I u I el

SI Ghl 14 LEG LLE

SITE F CH E F1C F.L .TLQE SO E ACT 10 NS

Hrtrrorss

3KINI al EI and dpi lyarly.por dx. xrnlnoacid lykc

Inc mix-1;E. ticod pasim:In Marc ram, andmcintoltm

Coe reo: acInai al F arid E.Efold ida4 Pea iPai or holirs

alPacc. ma-cbtol tin or piccire-. caitP)hyclraric-.ancl lipids In mcez dz-uce.

E s 0Y3 y E.E-ro idallyallyaorc hola P:4

I ncluc 4c. 3 nd M3 h d ns. -saconcla rfAl SCKLEI I

Cit< boon tc o;i pane rya s p;pildc MI i SILK .:11G. 11 1:-11, AlyCOE01

IDICOICCFYATI

Ir ...WI)maw ca4ti dte.oPail gas

..1K- 111111- blood v.F.dsE.r1 MU la 1.35 Idairn I and many celiac CA I -was ci p p:41I;faE.r1 MU 13 1.35 many o:-1 raven io pp :4 Ifera

prOIT101:66. E-1.1 I tit Sad CC canal') LI2ez4z- al ra_rorei p mcsas sweat' or rha4i sx1:4-1E.

InhIbla cal Kona-Won:5 IMAMS gamanalulmr mahlx pircluclon

causas ygre.als ra dlaeu and bacoma- kaki.ha-ping is Inlam maim


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causes snximh mirm la Das io rabx: midis:al rawardylryya i 1:+_r. c. IsI tz-Lpas ploraln

pkeiin

d aiteadva. or dx. amino ac htildlrarota rri I I ars

J


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Sel berkomunikasi secara kinliawi : Signal-Reseptor

Molekul sinyal bekerja dengan konsentrasi rendah


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Contoh : Viagramerangsangdisekresikannya gas NO shgpemb.darah relax /melebar



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Col

41` H o r m o n e

(a) Intracellular receptors


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Mrt-1I

Altered transcription of specific genes

ErnRNA

r el kJ J L A W t i I Irigure iu-iv PI HIM CCM LAW; 111151r MCVII1MIMIC 111:01:11X11 Fl

MIL al Dining .1.a Ebx1vessel. 11:1! Sq.mre !reds

leafing b (116:4-1 c the

flood ye :A. iekasedby Nerve kfrrin:. in thehixdAterw:el :Aid& entkepelicelk

1-t make and rekase

YJIKI

rhroi

Epinefrin berikatan dengan


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Epinefrin berikatan denganReseptor

terikat protein G

HOCH2

+

HO 0 P HO

IOH D 0

UDP-glucose

epinefrinberikatan ke reseptor

b-adrenergik pada permukaan

Glycogen synthase

HOCH2 HOCR2

-a-'''\L/H OH

Glycogen (n + 1 residues}


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Glycogen phosphorylase

HOCH, HOCH,

ID

OH

sel hati dan adiposa.m 0

0 Pc 0pridineI

m 0UDP

Epinefrin yang berikatan denganreseptor menimbulkan efekberbeda :

HOCH2

\ 0

OIVL/OLO HO

OH 0

Glucose 1-phosphate0

( 3 E \ / / a

OH OHGlycogen (n residues)

- Epinefrin yang berikatan denganb-adrenergik pada sel otot jantung


4 peningkatan kontraksi otot


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4 peningkatan kontraksi otot4 supply darah meningkat

- Pada sel otot polos intestin 4 relaksasi otot- Pada sel otot polos saluran darah di ginjal, kulit,intestin4

reseptor lain receptor a2-adrenergik 4 arteri konstriksi


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Protein Reseptor :

cl 076,1, (7/C) Edracobrir



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ti 1-1111.0111171111 elm PIPI-PCITIVIIII


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111TRA CE L L C C FrTOre

rn I h-

tea phctic"

Fr

o 161I ma r

I ri lu lar

nrcif

Rgire 1E-9 Extracellular nignalrnolec-ult bind either to cell---,uriare receptors 1:c ID int OCdlular era:ant-1 or receptors. 1,11 Mos! Eigna rnaleculenare bilge and hydrophik and are therekce tread F~ CEISS Ihe

plasma membrane dhecilA i-Istead, they hi-d to cel-



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suiace rereptoin, whkh F. ILrn genelak one or

rnoielignalninnide I he tame! cel Carshown in Figur- 36-71. IR. 5o4ne Email I ydrophobic nignal

rnolewles, hy

diHuse acres-s the iargetceIrspl.wmaMIX-3 Fle a nd 21C I eraymes or hild

iniracellular nxeptors--eiiher rr ihe cyke,o1

-shown) or in ihe nucleuE.FIGUELE72Crl urin-s. ra-mpLorf rocoroix& ooly.rpoiric molocul4..Signalmolcruks will hind

an IF ra ch Lac is I i pl 3..i no rsrcp ro- r F i ro

wish a sh3ric info r.hi ih,7 co, 11 r ins BIT.

A-Pada membran sel : mol larut air i.e.neurotransmiter & hormon

peptida,GroF


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B-balam sel : Sinyal hormon yang larutlemak (steroid spt estrogen,progesteron, testosteron), asam

retinoat,Vit b, gas NO

1)dalam sitoplasma 2)dalam inti sel



Aktivasi Reseptor pada permukaan sel


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p p p

4 kelompok reseptor :

1. Reseptor terikat protein 6 (> 100)

Ligand - reseptor 4 aktifasi protein6

4 aktivasi/hambat suatu enzim 4mengaktivasi ion channel atau second messenger. Contoh : reseptor untukepinefrin (B-adrenergic), serotonin, glukagon

2. reseptor ion channel

Ligand - reseptor 4 perubahan konformasi reseptor 4 aliran ion tertentu

(K,Na,Ca,CI4 ubah potensial elektris pada membran sel. eg reseptorasetilkolin

3. reseptor yang berikatan dengan tirosin kinase

Reseptor tidak memiliki aktivitas katalitik.

Ligand - reseptor 4 stimulasi dimerisasi reseptor 4 interaksi dengan protein

tirosin kinase pada sitosol. Contoh : faktor tumbuh

4. Reseptor yang memiliki aktivitas enzimatik intrinsik

Reseptor memiliki aktivitas katalitik intrinsik.

Ligand - reseptor 4 katalisasi GTP 4 cGMP atau berperan sebagai proteinfosfatase 4 mengkatalisasi pelepasan fosfat dari dari fosfotirosin

(reseptortiftdiFiEkiii&M) 1-16ontoh : reseptor insulin
http://sel.eg/http://sel.eg/


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tiftdiFiEkiii&M). 6ontoh : reseptor insulin


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Penyampaian sinyal/informasi ke dalam sel


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EXTRACELLUIAR CIGNAL ry1OLECULERECEPTORPROTEIN


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Sinyal disampaikan ke sel

targetme a u mo e u n rase a -am

Inisiasi-

Sinyal berikatan dengan reseptor/ligan : "Enzyme-linked" & Protein G- Sinyal4 ligand 5 transformasi

sinyal ke morekul lain :"secondmessenger": C-AMP & Calcium

Amplifikasi- Amplifikasi sinyal yang

diterima:"cascades"protein kinase- bistribusi sinyal untuk pengaruhi

beberapa efek secara paralel2005 RRE/AB SITH ITB


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id NA Lod

cc am 1:4ai ciG r.

r=1 PNcli

qeNI g I rn-:- ul

'en a-al PK+.

J{ V I FEL ph -:- ph 1:4-1,4 km,E1 r. riqu I1-3 ry Frei

rop-I mr.

nr- i TIO ND

N L K U

Talk 16-4 Sant Respordes Pikdigikd b.)Pl.mpholipirse C Aciiiratkin


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WOLECULE

VD:whinla roh

turroxpO

kgiyktritK.

TARaET

TISSUE

Ilya!

3r):kgykkitg.ThEintin

I Foldy lc

wadi

rrn

ixcl

F isu re 1G-24 A ri&e in intrallularofficlk .15111111:' c-an grit tron-scriplion.

B imini? of a InK.Imonenets mil lerlo ieceplor can lead to

i he of aclen yl cyclaSe and a intracellular cyclic MelF! In the cylcc.:.I.

cyclic X.F.13 21C I ivate-3 M.A. which !henrrr:ore 3 ink the nucle-u-s and phcrsphorylater specilk ne regulatory ppateins-.Once Incc-phory la led. these- pcoleint--

stimula IFee transcription al a -sei ulst-re-r.. This lype- oF Agnaing pathway controlsmany pm.ce-rz-e-s ransin:g1011-1 FIcimone Eynthesit% in endocrine- cells

lc. the pp:duclion oF irrrol %Red inlns-teirn memory Ine Aclirated

can -also pIncc-pl-r:cy la le and !hereby

legula le- ol her p-oteint-- and era ynnes

lhe cylccA g:a-s indicalecl by the1'.e-r

Table 16-2 xnt Hormont-inductd it IRt 11)Mtdiabtd bv Cyclic AMP

EKIRdiCE LLLIA R


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E KIRdiCE L LLIA RSI GN AL 1.1 0 LEC LL E I..d pm !Inc.

..d Po 3IInc.

Ad pn 31 kw, ACT H,

-ELKat:41

ACTH

In c mos:. In hen nu nd I an rxdan

&ago Im2k.Ixern L] I Ii kdmn

cor I sol roman

t5J hough a I Dr re diva I ma !Erni ps. Is al I-61 DIVhe.11110M ECIIT6' nnimsgs ED km 120:41%brri la l'AIPIrilEnkRIS a 19 ati) mai d tycycl kANF:


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Respon sel terhadap sinyal


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A. 1 sinyal 4 1 tipe reseptor

aneka efek pada berbagai selbentuk sel, pergerakan,metabolisme, ekspresi gen

B. Setiap sel punya beraneka

ragam reseptor spesifikuntuk aneka sinyal selmemberi respon 4misalkan efek untukkelulusan hidup &

diferensiasi


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Langkah - langkah komunikasi Sintesa molekul sinyal oleh sel yang memberi sinyal

Pelepasan molekul sinyal oleh sel yang memberi sinyal

Transpor sinyal oleh sel target

Pen9ikatan sinyal oleh reseptor spesifik yangmenyebabkan

aktivasi reseptor tersebut

Inisiasi satu atau lebih jalur transduksi sinyal intrasel

Perubahan spesifik fungsi, metabolisme, atauperkembangan

sel

Pembuangan sinyal yang mengakhiri respon sel


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Pembuangan sinyal yang mengakhiri respon sel



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__,,._____----- t ---------,'CELL 0 1


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CELL 0 1TARGET(

Receptor proteinCellular response: activation of a gene andsynthesis of new protein

New proteinS t e r o i dhormone

ANIMASI :

Steroid hormones bindto

intracellular receptors

- The steroid-receptor

complex binds to DNA,

turning specific genes on oroff (receptor act as gene


45/83

off (receptor act as generegulator)

In this example, a new

Other: act as Enzymes, eg.NO-guanylyl cyclase-catalyzesynthesis. of GMP


protein is synthesized


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(1) A hormone binds to a receptorprotein in the plasma membrane

(1) The receptor protein activatesa signs

I Hormone (epinephrine)

RECEPTOR PROTEIN

I----------

Plasma membraneTARGET CELL


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transduction pathway in the cell

(1) A series of relay moleculestransmits the signal to a protein

that carries out the cell's


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mornrams%yi xrla

I d.C41'.4iis44.i4449brpor,Key (b) p trAve,,,Ad cic"

' Signal and 4.CUI;

I C.01 AIM* W4pX

APAZ/ 1 -_Ftr:1:61 paw C

1.-E

roltr

C5100-7-411

(

6 -,11./L'IlL51

' 4


50/83

naunaLmangirm rcrcror Linalm 133 a mignal 3ngl-

ihnmoh 3

C.prarrin, mvrrvchcmcnhrits.bomdcvymc. daulyd4claLThiarmtiincoy.JtizachcrirE ii.of r ti1P,whkfr kin&aothecola chc .:166r i'LL:Th %lb:6m p:Elm3y. An cor3...clImbr rci=pixf Enka c

3nd. 3n.xhcr C rakloc..1croyinc phomphdipacC. Milcnrynczciiinisci. ikK pmgluccic.n irmic.1'did" linelo CO 3nel or ro colduoi .A11111{11 in ihr mirink.rarE cl.E nnekplmiir roiruhm. C3 dfr ...lino
http://c.mil/http://c.mil/http://c.mil/http://c.mil/


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ion-channellinked receptors

Nicotine


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Morphine and heroin Curare

Strychnine

constriction of blood vessels; elevation of blood pressure

analgesia (relief of pain); euphoriablockage of neuromuscular transmission, resulting in paralysis

seizures and muscle spasm

I


Cell surface proteins mediate cell-cell interactions.


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Cell 5 Jaringan :

misal darah dan otot


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Emory- call coacolnx a Jpciin arryo1rArle4 r prouia.

on ic.P furkoc Tliama ma rkan id4aciFy4scli ryp4cacti! is a -ms 7 p r4 tha w zy.

FICURE7.14

ir um, ri of dn. imuixtlobulio F.:Lily oicill iurfk:a surkir Fain. T 3rEl E all rusFica kip richrt chs

irrrnurc rapmE in orEprirra by nsq3nOin!mi kindriBN kaign oil rrcrkaz MEE NI ciBcm 131x1 allz

3:c 'Klf.' m chz clic inminc Flicrn 3 MIAS anIF irrradingcrtib, luch E. Ixrixii rim; rd ilanllysisn

Lim all of IrriThrial arBril!


56/83

1. Glikolipid : umum padapermukaan sel, mis: gol.darah

2. Protein"Majorhistocompatibilitycomplex"(MHC) untuk

membedakan "self" dengan"non-self",eg. imunoglobulin

Adhesi antar sel pada jaringan dan matrik : "CellJunction"


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Junction

Tiga kelompokcell junction:

1. occluding junctions: i.e. tight junctions 4 hanya vertebrate

2. anchoring junctionsA - berikatan dengan filamin aktini. sel-sel - (mis. Adhesion belts)i. sel-ECM - (mis. focal contacts)

FECLIELE7. L.

2005,RRE/AB,SITH ITBTin clina 9,Fa.p of rill junccionr. Than chrcc int-ichrcprvsni ..irrcnc chinkinEi an hvo.an luncurn of the cErcc mkt i!.pci. af rdl junakro. laciicsc chOr funaim: (r) OBI%

nacbn; (6) 3nchuring juscion; 6.) rprimmnicnino junccian.


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B. -berikatan dengan filamen intermediat

i. sel-sel (desmosom)i. sel-matriks (hemidesmosom)

3. Communicating junctiona. Gap junctions

b. Chemical synapsesa. Plasmodesmata (pada tumbuhan)

LuTpiin

lowialAitliiliit,.,..

a


59/83

htimilkiar Tram-Anal:4mA Prtnadal 4 411

Amino! kiktig prokdre.k. PIZ na

MCC Magnarwritcri 6


60/83

ib)Armhorti Ell (a)

is inoluidlon

Tight junctions : menghubungkan mbr plasma sel ygbersebelahan

1 barier selektif permeabilitas:mempertahankan perbedaan


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1. barier selektif permeabilitas:mempertahankan perbedaankomposisi cairan pada sisi sel yang berbeda

1. transmembran protein : claudin & ocludin

2. fungsi : -Men jags komposisi seny. dlm rongga saluran /lumen

-Transport nutrisi secara selektif

Tight junction antara sel epitel berperan untuk mencegah difusi :1. barrier untuk difusi protein membr antara domain apical

dan membran basolateral

B L O O D


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2. mencegah kebocoran P.1molekul larut air

i h j i

Anchoring junctions :

1. banyak pada sel yang mendapatkan stress mekanik ie.kulit/otot


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2. menghubungkan sitoskelet sel dengan sel lain atau dengan ECM

Ada 3 jenis :1. Adherens junctions 4 Filamen aktin

2. besmosom 4 filamen intermediate3. Hemidesmosom


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cy toske le ta l f i lamentsa n c h o r i n g j u n c t i o n s

extracellular matrix

Figure 19-6 Anchoring junctions in an epithelial tissue. Highly schematized

drawing of how such junctions join cytoskeletal filaments from cell to cell and fromcell to extracellular matrix.


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Figure 7,17 burst Hdhulioniare litemwheNcelk adlieNto likil imkgraiL lib.10veil hNS liecii rtaiuod wishiluureoeentantibudiamrevealIl1101460iI .1k Millli1S111.itrr4y.grtcn) and dic integnm (real.The Luepiniareb

Plized in small pighen (hit wtopundlu the ritc , of roalli,herionni (h/The cyroplarmic surlace my lined 4betionkie oliwd ophibimcrll isdrown here hrihe innereinfraell the membrane wirrinirpidaninen,deinp.eniinely r k. bundles ofnibsolibinaema are gen ronaaarinieteik ik inner surface of Memenihme in the regien nja Swat inbinkr (al Salicimil indrawimr ofthigIldhsion Aniq 11)e limric. (ohofirogriPglvhorawItlfulhrrprotciornnbothIdern the lipidbiluyer, The binding of mmelbdui bolik yell ONFII Allditrunectin, is lhoughr induachanges bi the ryillaninie CIMINIM1/ of the inkgrin thategg. the inregrinr to become linked rri pplig 56111Mhorrhcey. hq,bdrob. Linkages with Ilic,...ycolikelekon lead,;II NMI, ED lb ElthRling 11111141t11 MAI Linbagrr with therytuskeleton arc rn eclided by Yariaila da6n hbuf qkrokba.,01 as olio and a,laioin,tbalbind in Ili bednnlildlhrlmrpM The eytor 'amnia domain,ntegrinsareahuassk'ialedwlh

edFA UivalioikinauJ.'I'heat

.The rachirenronrheinreArin In yn tNifoolbild bgaud candicit pmtcin k oases and start o chin rpo rant that tanningignolo 1114.414;ct11, !Pia IMAM IMM1111004CIIES SI. di,Mhy 1997;s:110MS.011'1.1./*

MI1141111 III). tlI fht,J.CR1/101..112:4fli, iii,i;NPPIVIIIII.1:1011w 111.Ru:unlitlbirtssit tenet,.)

Cy10901

iransmilied1n Ilk nunieuri

Adherensjunctions


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adherens junctions sel/ sel :

adhesion belt/zonula adherens- dekat ujung apeks sel, di bawah tight junctions,

Filamen : aktin- protein pengikat trans membran : cadherin4mol.

adhesi bergantung Ca2+ : gen yg mengatur "nasib"

sel- protein pelekatan intracellular: catenin, vinculin, a-actinin, platoglobin


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distribution of desmosomrs and hemIdesmounues In iheltrahllrilint. he keratin Olarnrnl IICIWOrki ofildireerb contreered rra one anolhcr hrough dinrnsisurrinSrains ititiniKb k7unudvsnifiNdEneS. MAI

adherens junctions sel / matriks:Focal contacts/adhesion plaques- protein pengikat trans membr: integrin(>20)- protein pelekatan intraselular: talin,a-actinin,

vinculin- Filamen : aktin



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Plaque containing protein plectinCytoplasm

Plasma membrane

BP18O

Intermediate

filaments

space #11 IF;#11(100:411h.111)11.111,17!ExtracellularALIVA WAN7:41,-)

101Basement membrane

Anchoring filament (Laminin-5)Collagen

fibersb) Type VII Collagen fibrils

Figure 7.18 Hemidesmosomes are differentiated sites at the basal surfacesof epithelial cells where the cells are attached to the underlying basement membrane.

(a) Electron micrograph of several hemidesmosomes showing the dense plaque onthe inner surface of the plasma membrane and the intermediate filaments projecting

into the cytoplasm. (b) Schematic diagram showing the major components of ahemidesmosome connecting the epidermis to the underlying dermis. The ot,p,

integrin molecules of the epidermal cells are linked to cytoplasmic intermediatefilaments by a protein called plectin that is present in the dark-staining plaque and

to the basement membrane by anchoring filaments of a particular type of laminin. Asecond transmembrane protein (8P180) is also present in hemidesmosomes. The

collagen fibers arc part of the underlying dermis (A:


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collagen fibers arc part of the underlying dermis. (A:

FROM DOUGLAS E. KELLY, J. CELL BIOL. 28:51, 1966; BY COPYRIGHT nILMJSSION OF THEROCKEFELLER UNIVERSITY PRESS.)

besmosom hemidesmosom:menarik dan mengikat sangat kuat

penyebaran tekanan melalui epitel ke

ECM di bawahnya

2.besmosorn: sel - sel ,- anchoring sites untuk filamen

intermediate- trans membr linker protein:

cadherin

3.Hemidesmosorn:sel- ECM- Filamen intermediate : keratin- Transmembran protein : integrin



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itar. a F I G U R E 2 2 - 8 S t r u c t u r e o f g a p j u n c t i o n s . ( a ) I n t h i s m o d e l . a gap junction is a cluster ofchannels between two plasma membranes that are separated by a gap of about 2-3 nm. (b) B o t h m e m b r a n e s c o n t a i nc o n n e x i o n n e r n i c h a n n e l s , c y l i n d e r s o f six dumbbe ll- shap ed c onnexin subunits. (c1 Each connexin subunit hasfour transroembrane ay- helices Two connexons join in the gap between the cells to form a gap-junction channel. 1.52.0 nm in diameter.that connects the cytoplasm of the two cells.

eb}

F i g r u 7 . 4 . T h e L a c a l i z a t i c n i o f e a t l h e i r i n s i n s y n a l p r i c j i a t i c t-i tts- (ea) D ne tech n:..gtieto localize a protein thin a seheel1Llar region is to incubate tissue sections with labeled an rihndies !prepared a_gair-i,t thatprotein_ In this electron rraicr -oK-rapEt. a section through a s -saapse in a mouse brain has been incubated

antibodies Chlack grains) a h,ar bind ro a praecadherin. The protocadhe ri Locali,ed within thecentral re-gion of the si.tiaptie Kinction. (A) _A. model ofa syriapificin -whack-, classical cadherifly-hickcontain five extracellnlat -mains) are situated at the edges of the s.-napse where they-aretlaouerht to pro-..ide adhesion herween the nne-- and po.ts1tiap6r. membranes_ Protric ad ben (-which contain six eiciracellulaemains) are present in the center of the synapse chew areEl-Nonni-it to nne--diate speeifielev- in the interaction between therwo rare NICILECC7,31r-rr r 171- xu flint rv-r, 11-7 1

Communicating Junctions :komunikasi sitoplasma Iangsung dgn selsek


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Gap junctions : antara sel-sel- transmembran protein: connexon4tdr

atas 6 connexin- dapat dilalui oleh ion anorganik danmolekul larut air < 1000 ba, mis.gulasederhana, as amino

- menyampaikan sinyal elektris dan

kimiawi : mis kerusakan sel & sinaps

Pd tumbuhan : plasmodesmata

Synaptic junction

- sel saraf- diperantarai oleh protocadherin


Summary : Junction eit nonjunction


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F i g l i r p , 1 4 - 2 R A s u m m a r y of the


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2005,RRE/AB,SITH ITBjunctional and nonjunct ional adhesive mechanisms used byanimal cells in binding to one another and to the extracellular matrix.The junctional mechanisms are shown in epithelial cells, while the nonjunctional mechanisms

are shown in nonepithelial cells. A junctional interaction is operationally defined as one thatcan be seen as a specialized region of contact by conventional and/or freeze-fracture electronmicroscopy. Note that the integrins and cadherins are involved in both nonjunctional andjunctional cell-cell (cadherins) and cell-matrix (integrins) contacts. The cadherins generallymediate homophilic interactions, whereas the integrins mediate heterophilic interactions (seeFigure 19-26). Both the cadherins and integrins act as transmembrane linkers and depend onextracellular divalent cations to function; for this reason, most cell-cell and cell-matrixcontacts are divalent-cationdependent. The selectins and integrins can also act asheterophilic cell-cell adhesion molecules: the selectins bind to carbohydrate, while the cell-

binding integrins bind to members of the immunoglobulin superfamily. The integrins andintegral membrane proteoglycansthat mediate nonjunctional adhesion to the extracellular matrix are discussed later.

Extracellullar matrix


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LammProteoglycanFibronectin

PatI)))tpilipi, elk. ono"

.1;;:iggiiiNisiononsintoF4omiriiii,Zslott411 j

rof./111,111 ; 10'0111 '0

11. ** es 111, 111 !lo

li.1

:;'

ina It I) 1111 167:11:11111:4 114

es, i'vt

,k .)

014,1 6,oi

berperan dalam menentukan


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berperan dalam menentukanbentuk dan aktivitas sel.

mempertahankan kondisi selyang telah terdiferensiasidan mempertahankankemampuan sel untukmenghasilkan produknya



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Basal membran (BM):


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LamininEntestin

A FIGURE 22-20 Model of the basal lamina. P. D. Yurchenco and J C Schittny, 1990, FASO J. 4: 1577-15901

(EP MUAdaiat Epithelial sheerLUMENBasal laminaConnective ties LieConnective tisane Basal lemMa Muscle cell PlasmEpithelial cella membraneBasal lamingLel Kidney glomarulue

Endothelial eel

BL000

suatu organ,


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suatu organ, sebagai suatu barier

makromolekul & untuk invasisel ke suatu jaringan



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