Peroksizom: Revizyonlar arasındaki fark

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==Protein nakli==
Proteinler seçilmiş bir biçimde peroksizomlara aktarılırlar.peroksizom içerisinde DNA ya da ribozom barındırmadığı için tüm proteinlerini membranından nakille alır.temel proteinlerin oluşum esansında endoplazmik retikulumdan nakledildiği sanılmaktadır.ü
A specific protein signal (PTS or [[peroxisomal targeting signal]]) of three amino acids at the ''[[C-terminus]]'' of many peroxisomal proteins signals the membrane of the peroxisome to import them into the organelle. Other peroxisomal proteins contain a signal at the ''[[N-terminus]]''. There are at least 32 known peroxisomal proteins, called [[peroxin]]s,<ref name="pmid17050007">{{cite journal | author = Saleem RA, Smith JJ, Aitchison JD | title = Proteomics of the peroxisome | journal = Biochim. Biophys. Acta | volume = 1763 | issue = 12 | pages = 1541–51 | year = 2006 | pmid = 17050007 | doi = 10.1016/j.bbamcr.2006.09.005| url = http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=1858641&blobtype=pdf }}</ref> which participate in the process of importing proteins by means of ''[[ATP hydrolysis]]''. Proteins do not have to unfold to be imported into the peroxisome. The protein receptors, the peroxins ''[[PEX5]]'' and ''[[PEX7]]'', accompany their cargoes (containing a PTS1 or a PTS2, respectively) all the way into the peroxisome where they release the cargo and then return to the [[cytosol]] - a step named ''recycling''. Overall, the import cycle is referred to as the ''extended shuttle mechanism''.
Evidence now indicates that ATP hydrolysis is required for the recycling of receptors to the [[cytosol]]. Also, [[ubiquitination]] appears to be crucial for the export of PEX5 from the peroxisome, to the cytosol. Little is known about the import of PEX7, although it has helper proteins that have been shown to be ubiquitinated.
 
==Eksiklikler==
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