Details

Autor(en) / Beteiligte

• Yamamoto, Hayashi
• Shima, Takayuki
• Yamaguchi, Masaya
• Mochizuki, Yuh
• Hoshida, Hisashi
• Kakuta, Soichiro
• Kondo-Kakuta, Chika
• Noda, Nobuo N.
• Inagaki, Fuyuhiko
• Itoh, Takehiko
• Akada, Rinji
• Ohsumi, Yoshinori

Titel

The Thermotolerant Yeast Kluyveromyces marxianus Is a Useful Organism for Structural and Biochemical Studies of Autophagy

Ist Teil von

• The Journal of biological chemistry, 2015-12, Vol.290 (49), p.29506-29518

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2015

Quelle

MEDLINE

Beschreibungen/Notizen

• Autophagy is a conserved degradation process in which autophagosomes are generated by cooperative actions of multiple autophagy-related (Atg) proteins. Previous studies using the model yeast Saccharomyces cerevisiae have provided various insights into the molecular basis of autophagy; however, because of the modest stability of several Atg proteins, structural and biochemical studies have been limited to a subset of Atg proteins, preventing us from understanding how multiple Atg proteins function cooperatively in autophagosome formation. With the goal of expanding the scope of autophagy research, we sought to identify a novel organism with stable Atg proteins that would be advantageous for in vitro analyses. Thus, we focused on a newly isolated thermotolerant yeast strain, Kluyveromyces marxianus DMKU3-1042, to utilize as a novel system elucidating autophagy. We developed experimental methods to monitor autophagy in K. marxianus cells, identified the complete set of K. marxianus Atg homologs, and confirmed that each Atg homolog is engaged in autophagosome formation. Biochemical and bioinformatic analyses revealed that recombinant K. marxianus Atg proteins have superior thermostability and solubility as compared with S. cerevisiae Atg proteins, probably due to the shorter primary sequences of KmAtg proteins. Furthermore, bioinformatic analyses showed that more than half of K. marxianus open reading frames are relatively short in length. These features make K. marxianus proteins broadly applicable as tools for structural and biochemical studies, not only in the autophagy field but also in other fields. Background: Autophagosome formation is mediated by multiple autophagy-related (Atg) proteins. Results: Essential Atg proteins of K. marxianus, which have superior thermostability and solubility, are identified. Conclusion:K. marxianus can be used as a novel organism to study autophagy. Significance:K. marxianus proteins are broadly applicable as tools for in vitro studies, not only in autophagy field but also in other fields.