Peroxisome biogenesis

Citation
Pe. Purdue et Pb. Lazarow, Peroxisome biogenesis, ANN R C DEV, 17, 2001, pp. 701-752
Citations number
230
Language
INGLESE
art.tipo
Review
Categorie Soggetti
Cell & Developmental Biology
Journal title
ANNUAL REVIEW OF CELL AND DEVELOPMENTAL BIOLOGY
ISSN journal
1081-0706 → ACNP
Volume
17
Year of publication
2001
Pages
701 - 752
Database
ISI
SICI code
1081-0706(2001)17:<701:PB>2.0.ZU;2-E
Abstract
Fifteen years ago, we had a model of peroxisome biogenesis that involved gr owth and division of preexisting peroxisomes. Today, thanks to genetically tractable model organisms and Chinese hamster ovary cells, 23 PEX genes hav e been cloned that encode the machinery ("peroxins") required to assemble t he organelle. Membrane assembly and maintenance requires three of these (pe roxins 3, 16, and 19) and may occur without the import of the matrix (lumen ) enzymes. Matrix protein import follows a branched pathway of soluble recy cling receptors, with one branch for each class of peroxisome targeting seq uence (two are well characterized), and a common trunk for all. At least on e of these receptors, Pex5p, enters and exits peroxisomes as it functions. Proliferation of the organelle is regulated by Pex11p. Peroxisome biogenesi s is remarkably conserved among eukaryotes. A group of fatal, inherited neu ropathologies are recognized as peroxisome biogenesis diseases; the respons ible genes are orthologs of yeast or Chinese hamster ovary peroxins. Future studies must address the mechanism by which folded, oligomeric enzymes ent er the organelle, how the peroxisome divides, and how it segregates at cell division. Most pex mutants contain largely empty membrane "ghosts" of pero xisomes; a few mutants apparently lacking peroxisomes entirely have led som e to propose the de novo formation of the organelle. However, there is evid ence for residual peroxisome membrane vesicles ("protoperoxisomes") in some of these, and the preponderance of data supports the continuity of the per oxisome compartment in space and time and between generations of cells.