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Lisomes, indicating that the ria and chloroplasts and at , accompanies M cargo ail cycł« back out into the resetnble protriB tntnport

A Shorc Signs I Sequence Dirocts thę Import of Proteins Ir to Reroxisomes

A apecifie sequeace of three amino adds located at the C tenninus of many per-oxisomal protein* functions as an import signal (seetablc 12-3). Other peron-somal proteins c ontain a signai sequence near the N terminus. If elther of these sequenees is a perimentally atmehefl to i cytoscaic protein, the protein is imported into >eroxisomes. The import process U still poorly understood. althaugh it is kr dwo to łrtyolve solubie receptor proteins in the cytosoi (hit rac* ognłze the targe :ing signals, as wel) as doddng pro trans on the cytosolic surface • of ihe perojcisonc. Ar ieast 23 distinct proteins. cadjed pcroilns, participate as components in ihe process. WhJch is drlvcn by ATP pydrolytis. Oligomeric pro* tein* do not ha' e to unfold to ba imported Into pero mcchanism is t istinrt brom that used by mitochonc Ipitst n soiub | import receptor, the penndn Bpx! da| wav into nrtoxlsom** .ukI. fiAer cargo rrlea cytosoi These upeęts ofperoxitofli.nl protein Imt Uitn th* nudet

. The impnriaa^^^Łgtaport process and of p|ovtsonnps is demonstrared by tar HH9H j -PipPase ZtUuHgśr ryj

Rgure 11-13 Electron mirmigfci I of twa typcs of peraniionMS fmnUn plant celłs. (A) A perokOomc praęrnolitne core m a u&kcoM | mosopmrft wS ją don łnodMłotywra I chlcnłłbjtt it dKMjttt W fitStt* tfu I cachaim of mttmfc bmw* Sm .J ofjswam tłurthg pfaottfmłnao*

(B) PifBłf»ofnt» «»tu wpUf toomr ctll et i tonutc MSd 4 (byt i&e (•nmninort Htro. tfit pcrumonoi J (gWfNiw) *e nuoaM<#t4 9li bo4# Mwn b WWl flShc*| ■! cmoJ oł# ta %t    I

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