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Tap42-associated protein phosphatase type 2A negatively regulates induction of autophagy

Tomohiro Yorimitsu1, Congcong He, Ke Wang

  • 1Life Sciences Institute, Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109-2216, USA.

Autophagy
|February 19, 2009
PubMed

Insights

Autophagy regulation in yeast involves Tap42 and protein phosphatase type 2A (PP2A). This pathway negatively controls autophagy, impacting cellular homeostasis and function.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Autophagy is a crucial cellular degradation process in eukaryotes, essential for maintaining cellular homeostasis.
  • Precise control of autophagy levels is vital to prevent cellular dysfunction.
  • The Tor kinase complex 1 (TORC1) regulates autophagy induction, but its mechanisms require further elucidation.

Purpose of the Study:

  • To investigate the roles of Tap42 and protein phosphatase type 2A (PP2A) in regulating autophagy in yeast.
  • To elucidate the molecular mechanisms by which Tap42 and PP2A influence autophagy induction.

Main Methods:

  • Utilized temperature-sensitive mutant alleles of TAP42 to study autophagy induction.
  • Examined the effect of Tip41 (a Tap42-interacting protein) on autophagy.
  • Investigated the impact of PP2A inactivation and overexpression on autophagy.

Main Results:

  • Autophagy was induced in tap42 mutants independently of TORC1 inactivation.
  • Absence of Tip41 abolished autophagy induction in tap42 mutants, while Tip41 overexpression activated autophagy.
  • PP2A inactivation stimulated autophagy, whereas PP2A overexpression inhibited rapamycin-induced autophagy.

Conclusions:

  • The Tap42-PP2A pathway negatively regulates autophagy in yeast.
  • These findings provide new insights into the complex regulatory network controlling autophagy.

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