Open AccessGlucose‐induced and nitrogen‐starvation‐induced peroxisome degradation are distinct processes in Hansenula polymorpha that involve both common and unique genes
Author(s) -
Bellu Anna Rita,
Kram Anita M,
Kiel Jan A.K.W.,
Veenhuis Marten,
Klei Ida J
Publication year - 2001
Publication title -
fems yeast research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.991
H-Index - 92
eISSN - 1567-1364
pISSN - 1567-1356
DOI - 10.1111/j.1567-1364.2001.tb00010.x
Subject(s) - peroxisome , autophagy , biology , vacuole , microbiology and biotechnology , organelle , yeast , biochemistry , mutant , gene , saccharomyces cerevisiae , cytoplasm , apoptosis
In the methylotrophic yeast Hansenula polymorpha non‐selective autophagy, induced by nitrogen starvation, results in the turnover of cytoplasmic components, including peroxisomes. We show that the uptake of these components occurs by invagination of the vacuolar membrane without their prior sequestration and thus differs from the mechanism described for bakers yeast. A selective mode of autophagy in H. polymorpha , namely glucose‐induced peroxisome degradation, involves sequestration of individual peroxisomes tagged for degradation by membrane layers that subsequently fuse with the vacuole where the organelle is digested. H. polymorpha pdd mutants are blocked in selective peroxisome degradation. We observed that pdd1‐201 is also impaired in non‐selective autophagy, whereas this process still normally functions in pdd2‐4 . These findings suggest that mechanistically distinct processes as selective and non‐selective autophagy involve common but also unique genes.