Txhua lub xov tooj ntawm tes muaj cov txheej txheem uas ua rau nws ua kom pom tag nrho cov khoom ntawm lub cev muaj sia. Yuav kom ua haujlwm tau zoo, lub xovtooj ntawm tes yuav tsum tau txais cov as-ham txaus, rhuav tshem thiab tso tawm lub zog, uas yog siv los txhawb kev ua neej.
Thaum thawj theem ntawm cov txheej txheem nyuaj ntawm kev tswj hwm lub zog yog cov lysosomes ntawm lub xovtooj, uas yog laced raws cov npoo ntawm cov cisters flattened ntawm dictyosome (Golgi complex).
Lysosomes ua haujlwm li cas
Lysosomes yog ib leeg-membrane lub cev uas muaj txoj kab uas hla ntawm 0.2 mus rau 2 microns, uas muaj cov complex ntawm hydrolytic enzymes. Lawv muaj peev xwm zom tau tej yam ntuj tso polymer los yog cov khoom ntawm complex qauv uas nkag mus rau hauv lub cell raws li ib tug as-ham substrate los yog txawv teb chaws tus neeg sawv cev:
- proteins thiab polypeptides;
- polysaccharides (cov hmoov txhuv nplej siab, dextrins, glycogen);
- nucleic acids;
Ylipids.
Qhov kev ua tau zoo no yog muab los ntawm kwv yees li 40 hom enzymes uas muaj nyob hauvob leeg nyob rau hauv lub matrix ntawm lub lysosome thiab nyob rau sab hauv ntawm daim nyias nyias nyob rau hauv ib tug adherent xeev.
Lysosome Chemistry
Cov daim nyias nyias nyob ib puag ncig lysosome tiv thaiv cov organelles thiab lwm yam ntawm tes los ntawm kev zom los ntawm cov enzyme complex. Tab sis tom qab tag nrho, nyob rau hauv lub vesicle nws tus kheej, tag nrho cov enzymes yog cov protein keeb kwm, yog vim li cas lawv tsis tawg los ntawm proteases?
Qhov tseeb yog tias hauv cov lysosomes cov enzymes nyob rau hauv lub xeev glycosylated. Cov carbohydrate "plhaub" no ua rau lawv tsis pom zoo los ntawm cov enzymes proteolytic.
Cov tshuaj tiv thaiv ntawm ib puag ncig hauv lysosome yog me ntsis acidic (pH 4.5-5), nyob rau hauv sib piv rau qhov yuav luag nruab nrab cov tshuaj tiv thaiv ntawm hyaloplasm. Nws tsim cov xwm txheej zoo rau kev ua haujlwm ntawm cov enzymes thiab yog muab los ntawm kev ua haujlwm ntawm H+-ATPase, uas tso cov protons rau hauv lub cev.
Lysosome transformation process
Morphologically, ob lub ntsiab ntawm lysosomes yog qhov txawv hauv lub cell - thawj thiab theem nrab.
Primary lysosomes yog cov hlwv me me, du-walled los yog ciam teb, sib cais los ntawm cov cisterns ntawm Golgi complex. Lawv muaj ib txheej ntawm hydrolytic enzymes yav dhau los tsim ntawm granular (ntxhib) EPR daim nyias nyias. Txog rau thaum nqus ntawm cov as-ham substrate, lysosomes nyob rau hauv daim ntawv tsis muaj zog.
Rau cov enzymes ua haujlwm, cov khoom noj lossis cov kua dej yuav tsum nkag mus rau lysosome. Qhov no tshwm sim nyob rau hauv ob txoj kev:
- Los ntawm autophagy, thaum cov khoom noj khoom haus tau coj los ntawm lysosome los ntawm ib puag ncig cytoplasm. Hauv qhov no, daim nyias nyias ntawm lub organelle invaginates ntawm qhov chaw ntawm kev sib cuag nrog cov particlethiab tsim cov hlab ntsha endocytic, thiab tom qab ntawd laces rau hauv lysosome.
- Los ntawm heterophagy, thaum lub lysosome fuses nrog endocytic vesicles daig nyob rau hauv lub cytoplasm ntawm lub xovtooj ntawm tes vim yog nqus ntawm cov khoom los yog kua los ntawm sab nraud.
Secondary lysosomes yog vesicles uas muaj ob qho enzymes thiab substrate rau kev zom. Lawv yog tus cwj pwm los ntawm kev ua haujlwm hydrolytic thiab raug tsim los ntawm kev nqus ntawm cov substrate los ntawm thawj lysosome.
Txawm hais tias qhov kev ua haujlwm ntawm lysosome tau txo qis rau kev zom zaub mov (sib cais) ntawm cov khoom organic thiab cov tshuaj yaj, cov txheej txheem ntau yam tau lees paub los ntawm lub peev xwm ntawm cov lysosomes thib ob:
- merge nrog thawj lysosomes uas coj los rau hauv ib feem tshiab ntawm enzymes;
- fuse nrog cov khoom noj tshiab lossis cov hlwv endocytic, tswj cov txheej txheem tsis tu ncua;
- fuse nrog lwm cov lysosomes theem nrab los tsim cov qauv loj uas muaj peev xwm nqus tau lwm cov cell organelles;
- nqus cov vesicles pinocytic, tig mus rau hauv lub cev multivesicular.
Cov qauv ntawm lysosome tsis hloov pauv ntau. Nws feem ntau tsuas yog nce qhov loj.
Lwm hom lysosomes
Qee zaum kev tawg ntawm cov tshuaj uas tau nkag mus rau hauv lysosome tsis mus txog qhov kawg. Undigested hais tsis raug tshem tawm ntawm lub organelle, tab sis nyob rau hauv nws. Tom qab muab cov enzymes hydrolytic depleted, cov ntsiab lus yog compacted thiab ua tiav, cov qauv ntawm lysosome ua complex, txheej. Pigments kuj tuaj yeem tso. Lub lysosome hloov mus rau hauv lub cev seem.
Ntxiv mus, lub cev seem tseem nyob hauv cell lossis raug tshem tawm los ntawm exocytosis.
Autophagosomes tuaj yeem pom hauv cov cell protist. Los ntawm lawv cov xwm, lawv nyob rau theem nrab lysosomes. Hauv cov organelles, cov seem ntawm cov cell loj thiab cov qauv cytoplasmic pom. Lawv tsim thaum lub sij hawm cell puas, kev laus ntawm cov organelles ntawm tes thiab ua hauj lwm rau siv cell Cheebtsam, tso monomers.
Kev ua haujlwm ntawm lysosome hauv cell
Lysosomes, ua ntej ntawm tag nrho, muab lub cell nrog cov khoom tsim nyog tsim, depolymerizing tshuaj uas tau nkag mus rau nws.
Kev tawg ntawm carbohydrates yog qhov txuas tseem ceeb hauv lub cell lub zog metabolism, muab lub substrate rau kev hloov pauv hauv mitochondria.
Lysosomes kuj yog qhov txuas tiv thaiv hauv lub cev tiv thaiv kab mob:
- Tom qab phagocytosis ntawm cov kab mob los ntawm leukocytes, lysosomes nchuav lawv cov ntsiab lus rau hauv kab noj hniav ntawm phagocytic vesicle thiab rhuav tshem cov kab mob phem.
- Tshuaj proteolytic enzymes thaum apoptosis - programmed cell tuag.
- Siv puas thiab "laus" cell organelles.
Ua ke nrog kev loj hlob ntawm tes, kev koom tes ntawm lysosomes hauv cov txheej txheem ntawm kev siv ntau yam qauv ua kom lub cev rov ua dua tshiab.
