Peroxisomal targeting signal

Both the integral membrane proteins of peroxisomes as well as the peroxisomal matrix proteins are synthesised on free polyribosomes and are specifically targeted to peroxisomes via dedicated peroxisomal targeting signals. The biogenesis of peroxisomes follows a sequential pattern, which involves first the insertion of peroxisomal membrane proteins into the membrane of the pre-peroxisomal structure, derived from the endoplasmic reticulum, followed by insertion of the various matrix proteins. 

Neuberger G, Maurer-Stroh S, Eisenhaber B, Hartig A, Eisen-haber F. 2003. Prediction of peroxisomal targeting signal 1 containing proteins from amino acid sequence. J Mol Biol 328 581-592. 

S winkels BW, Gould S J, Bodnar AG, Rachubinski RA, Subramani S. A no vel. cleavable peroxisomal targeting signal at the amino-terminus of the rat 3-ketoacyl-CoA thiolase. EMBO J 1991 10( 11) 3255—3 262. 

The gene coding for catalase in the human consists of 13 exons and is located on chromosome llpl3 The hiunan catalase promoter is GC-rich,lacks a TATA box, and has several putative Sp-1 binding sites [219]. The peroxisomal targeting signal is located approximately eight amino acids from the C-terminus in mammalian catalases and are SHI, SHM, and SHE for rat and mouse hver catalases and human kidney catalase, respectively [220]. 

Dammai, V., and S. Subramani. 2001. The human peroxisomal targeting signal receptor, Pex5p, is translocated into the peroxisomal matrix and recycled to the cytosol. Cell 105 187-196. 

A3.5,A2.4-Dienoyl-CoA isomerase is a member of the hydratase/isomerase superfamily with a 32-kDa subunit in a homohexameric arrangement (R.K. Wierenga, 1998). It is present in both mitochondria and peroxisomes because of mitochondrial and peroxisomal targeting signals at its N-terminus and C-terminus, respectively. The crystal structure of... 

Olivier, L.M., Krisans, S.K. 2000. Peroxisomal protein targeting and identification of peroxisomal targeting signals in cholesterol biosynthetic enzymes. Biochim. Biophys. Acta 1529 89-102. 

Kragler, F., Langeder, A., Raupachova, J., Binder, M. and Hartig, A. (1993) Two independent peroxisomal targeting signals in catalase A of Saccharomyces cerevisiae. J. Cell Biol. 120 665-673. 

The import of proteins into peroxisomes is directed by peroxisomal targeting signals (PTSs) (Subramani, 1992). A carboxy-terminal tripeptide with the sequence SKL (in the one-letter amino acid code) represents a prototype PTS. Crosslinking of a peptide ending in SKL to a carrier protein creates an artificial substrate for the peroxisomal import machinery (Walton et al., 1992). 

Walton, P. A., Gould, S. J., Feramisco, J. R., and Subramani, S. (1992) Transport of microin-jected proteins into peroxisomes of mammalian cells Inability of Zellweger cell lines to import proteins with the SKL tripeptide peroxisomal targeting signal. Mol. Cell. Biol. 12,... 

The fact that proteins destined for peroxisomes are synthesised on free polyribosomes implies that these proteins must possess specific signals to direct them to peroxisomes. Two of such Peroxisome Targeting Signals (PTS) have been identified. The first PTS involves a carboxyterminal tripeptide of the sequence serine-lysine-leucine (SKL) or a variant thereof and many peroxisomal proteins contain such a PTSl. 

Import receptor Pex5 Interaction with peroxisomal targeting signal 1 receptor 117... 

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