Biomaterial Database

Pexophagy: autophagic degradation of peroxisomes. 2006

Yasuyoshi Sakai, and Masahide Oku, and Ida J van der Klei, and Jan A K W Kiel

Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake, Kyoto 606-8502, Japan. ysakai@kais.kyoto-u.ac.jp

The abundance of peroxisomes within a cell can rapidly decrease by selective autophagic degradation (also designated pexophagy). Studies in yeast species have shown that at least two modes of peroxisome degradation are employed, namely macropexophagy and micropexophagy. During macropexophagy, peroxisomes are individually sequestered by membranes, thus forming a pexophagosome. This structure fuses with the vacuolar membrane, resulting in exposure of the incorporated peroxisome to vacuolar hydrolases. During micropexophagy, a cluster of peroxisomes is enclosed by vacuolar membrane protrusions and/or segmented vacuoles as well as a newly formed membrane structure, the micropexophagy-specific membrane apparatus (MIPA), which mediates the enclosement of the vacuolar membrane. Subsequently, the engulfed peroxisome cluster is degraded. This review discusses the current state of knowledge of pexophagy with emphasis on studies on methylotrophic yeast species.

UI	MeSH Term	Description	Entries
D008561	Membrane Fusion	The adherence and merging of cell membranes, intracellular membranes, or artificial membranes to each other or to viruses, parasites, or interstitial particles through a variety of chemical and physical processes.	Fusion, Membrane,Fusions, Membrane,Membrane Fusions
D010843	Pichia	Yeast-like ascomycetous fungi of the family Saccharomycetaceae, order SACCHAROMYCETALES isolated from exuded tree sap.	Hansenula,Hansenulas,Pichias
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001343	Autophagy	The segregation and degradation of various cytoplasmic constituents via engulfment by MULTIVESICULAR BODIES; VACUOLES; or AUTOPHAGOSOMES and their digestion by LYSOSOMES. It plays an important role in BIOLOGICAL METAMORPHOSIS and in the removal of bone by OSTEOCLASTS. Defective autophagy is associated with various diseases, including NEURODEGENERATIVE DISEASES and cancer.	Autophagocytosis,ER-Phagy,Lipophagy,Nucleophagy,Reticulophagy,Ribophagy,Autophagy, Cellular,Cellular Autophagy,ER Phagy
D014617	Vacuoles	Any spaces or cavities within a cell. They may function in digestion, storage, secretion, or excretion.	Vacuole
D020675	Peroxisomes	Microbodies which occur in animal and plant cells and in certain fungi and protozoa. They contain peroxidase, catalase, and allied enzymes. (From Singleton and Sainsbury, Dictionary of Microbiology and Molecular Biology, 2nd ed)	Peroxisome
D025062	Yarrowia	A genus of ascomycetous yeast in the family Dipodascaceae, order SACCHAROMYCETALES.	Yarrowia lipolytica,Yarrowias