Kazuyoshi Yonezawa
Biochemist on the founding raptor and PRAS40 papers, from the Kobe biosignal group
Biosignal Research Center, Kobe University, Japan
Researcher record (KAKEN), Kobe University ↗
Kazuyoshi Yonezawa led a biochemistry group at Kobe University's Biosignal Research Center that collaborated closely with mTOR labs in the United States through the early 2000s, contributing to some of the field's foundational papers on how mTOR recognizes its substrates.
His group co-discovered raptor as mTOR's substrate-presenting partner, showed that raptor binds mTOR's substrates p70 S6 kinase and 4E-BP1 through a shared TOS (TOR signalling) motif, and identified PRAS40 as a physiological mTORC1 substrate and insulin-regulated inhibitor — work that clarified both how mTORC1 recognizes what to phosphorylate and how insulin signalling relieves its own brake on the complex.
Yonezawa's own trail in this Atlas stops in the mid-2000s — not because his work stopped mattering, but because he died before finishing it: Japan's Science and Technology Agency (JST) recorded that his CREST-funded project on the proteins governing cell growth ended partway through "due to the death of the principal investigator" (研究代表者逝去により研究期間途中で終了), per its close-out report for the project.
The timeline below follows Yonezawa's contributions gathered in this Atlas.
Milestones in the Atlas
| Year | Evidence | Study |
|---|---|---|
| 2002 | M | Raptor, a binding partner of target of rapamycin (TOR), mediates TOR action HARA2002 Co-authors the identification of raptor as a binding partner that mediates mTOR's action. |
| 2003 | M | The mammalian target of rapamycin (mTOR) partner, raptor, binds the mTOR substrates p70 S6 kinase and 4E-BP1 through their TOR signaling (TOS) motif NOJ2003 Shows raptor binds the mTOR substrates p70 S6 kinase and 4E-BP1 through their TOR signalling (TOS) motif. |
| 2007 | M | The proline-rich Akt substrate of 40 kDa (PRAS40) is a physiological substrate of mammalian target of rapamycin complex 1 OSH2007 Shows PRAS40 is a physiological substrate of mTORC1, phosphorylated on Ser183. |