Múltiplos processos de transporte proteico para os peroxissomas: mero acaso, fortuita necessidade ou design inteligente?

segunda-feira, dezembro 07, 2015

Journal of Molecular Biology
Volume 427, Issue 6, Part A, 27 March 2015, Pages 1176–1190
Elucidation of Protein Translocation Pathways (Part II)

Multiple Pathways for Protein Transport to Peroxisomes

P.K. Kim1, 2, E.H. Hettema3, , 

1 Program in Cell Biology, Hospital for Sick Children, Toronto, ON, Canada M5G 1X8

2 Department of Biochemistry, University of Toronto, Toronto, ON, Canada M5S 1A8

3 Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, South Yorkshire S10 2TN, United Kingdom

Received 1 August 2014, Revised 5 February 2015, Accepted 6 February 2015, Available online 11 February 2015

Edited by S. High

Under a Creative Commons license


• Peroxisomal membrane and matrix proteins require distinct factors for their transport.

• Matrix proteins fold in the cytosol prior to their import.

• Loaded targeting receptors form part of the matrix protein translocation pore.

• Many membrane proteins are directly inserted into the peroxisomal membrane.

• Some peroxisomal membrane proteins are transported via the ER to peroxisomes.


Peroxisomes are unique among the organelles of the endomembrane system. Unlike other organelles that derive most if not all of their proteins from the ER (endoplasmic reticulum), peroxisomes contain dedicated machineries for import of matrix proteins and insertion of membrane proteins. However, peroxisomes are also able to import a subset of their membrane proteins from the ER. One aspect of peroxisome biology that has remained ill defined is the role the various import pathways play in peroxisome maintenance. In this review, we discuss the available data on matrix and membrane protein import into peroxisomes.


PMP, peroxisomal membrane protein; PTS, peroxisomal targeting signal; TA, tail-anchored


peroxisome; peroxin; protein import