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Makoto T Hayashi

@makotothayashi.bsky.social
107 followers 176 following 18 posts

Group leader at IFOM-KU joint lab is working on #chromosome biology, especially focusing on #telomere functions. Employed by IFOM ETS and running the lab at Kyoto University.

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Makoto T Hayashi @makotothayashi.bsky.social · 24/03/2026
Understanding t-loop plasticity offers a molecular explanation for senescence and crisis during aging and cancer. Read the full article here: x.gd/h0UGl
x.gd
T-loop dynamics: telomere structure shapes cell fate decisions
Telomeres are nucleoprotein elements bound by shelterin that protect chromosome ends from DNA damage signalling and inappropriate repair. A defining architectural feature is the telomere loop (t-loop)...
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Makoto T Hayashi @makotothayashi.bsky.social · 24/03/2026
We also propose the entangled telomere resolution hypothesis: the MAD pathway may be co-opted during normal anaphase to resolve sister-telomere entanglements (HR intermediates). This may ensure faithful chromosome segregation without telomere loss.
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Makoto T Hayashi @makotothayashi.bsky.social · 24/03/2026
We propose this MAD pathway functions as a "mitotic timer," removing damaged cells from the proliferative pool to prevent chromosomal instability. It links “intermediate” telomere architecture to mitotic quality control.
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Makoto T Hayashi @makotothayashi.bsky.social · 24/03/2026
We highlight Mitotic Arrest-Dependent (MAD) telomere deprotection. This is an active, regulated pathway triggered by prolonged mitosis, where t-loops are unwound via an AURKB-BTR (BLM, TOP3A, RMI1/2) axis, causing an ATM-dependent DNA damage response (intermediate state).
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Makoto T Hayashi @makotothayashi.bsky.social · 24/03/2026
Our framework is built upon the Three-state model, originally proposed by ‪@thecesarelab.bsky.social‬. It categorizes telomeres into closed, intermediate, or uncapped states. Notably, the intermediate state is unique: it triggers a DNA damage response but resists fusion.
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Makoto T Hayashi @makotothayashi.bsky.social · 24/03/2026
T-loops are lariat structures that sequester and protect chromosome ends. They are now recognized as dynamic DNA architectures that are remodeled during the cell cycle and in response to stress, acting as a signaling platform.
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Makoto T Hayashi @makotothayashi.bsky.social · 24/03/2026
I’m thrilled to share our new review in @cp-trendscellbio.bsky.social! This was a wonderful collaboration with my friend ‪@thecesarelab.bsky.social‬, and I truly enjoyed our writing process. We explore "T-loop Dynamics: Telomere Structure Shapes Cell Fate Decisions." x.gd/h0UGl 🧵
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Reposted by Makoto T Hayashi
Tony Cesare @thecesarelab.bsky.social · 23/03/2026
“T-loop Dynamics: Telomere Structure Shapes Cell Fate Decisions” is out now in @cp-trendscellbio.bsky.social . www.cell.com/trends/cell-... It was a pleasure to work on this with collaborator and friend @makotothayashi.bsky.social, whose insight was central to shaping the ideas in this review.
cell.com
T-loop dynamics: telomere structure shapes cell fate decisions
Telomeres are nucleoprotein elements bound by shelterin that protect chromosome ends from DNA damage signalling and inappropriate repair. A defining architectural feature is the telomere loop (t-loop)...
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Makoto T Hayashi @makotothayashi.bsky.social · 17/03/2025
Thrilled to see our work published! Huge thanks to all my co-authors for the great collaboration!!
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Makoto T Hayashi @makotothayashi.bsky.social · 17/03/2025
10/10 For a more detailed explanation, check out bsky.app/profile/thec... for an in-depth thread on our findings.
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Makoto T Hayashi @makotothayashi.bsky.social · 17/03/2025
9/10 These insights not only advance our understanding of telomere biology but also opens potential therapeutic avenues for targeting mitotic death in cancer cells.
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Makoto T Hayashi @makotothayashi.bsky.social · 17/03/2025
8/10 Our findings support a dynamic model where coordinated post-translational modifications of shelterin promote t-loop unwinding, aiding in the removal of damaged cells from the cell cycle.
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Makoto T Hayashi @makotothayashi.bsky.social · 17/03/2025
7/10 This phosphorylation is essential for BTR-mediated double Holliday junction dissolution and contributes to mitotic telomere deprotection, highlighting a previously underappreciated role of the shelterin complex.
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Makoto T Hayashi @makotothayashi.bsky.social · 17/03/2025
6/10 Shelterin is a telomere-binding protein complex that includes TRF1 and TRF2, crucial for maintaining telomere structure and function. During mitotic arrest, Aurora Kinase B (AURKB) of the CPC phosphorylates TRF1 and TRF2, leading to telomere linearity and a telomere-specific DDR.
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Makoto T Hayashi @makotothayashi.bsky.social · 17/03/2025
5/10 Our study uncovers a sophisticated mechanism involving the Chromosome Passenger Complex (CPC), the shelterin complex, and the BLM-TOP3A-RMI1/2 (BTR) complex in regulating MAD-telomere deprotection.
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Makoto T Hayashi @makotothayashi.bsky.social · 17/03/2025
4/10 Telomeres safeguard chromosome ends by forming t-loops, preventing ATM activation and unwarranted DNA damage responses (DDR). However, during mitotic arrest, telomere linearity and a localized DDR emerge—a phenomenon known as "Mitotic Arrest Dependent (MAD)-Telomere Deprotection."
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Makoto T Hayashi @makotothayashi.bsky.social · 17/03/2025
3/10 Additional key contributors include Ronnie Low, Scott Page, Blake Lane, Andrew Robinson, and Lucy French from @thecesarelab.bsky.social. Fuyuki Ishikawa from Kyoto University and Shunya Kosaka from my lab.
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Makoto T Hayashi @makotothayashi.bsky.social · 17/03/2025
2/10 This work highlights the power of collaboration. Special thanks to our fantastic collaborator @thecesarelab.bsky.social. Diana Romero from my lab and Sam Rogers from Cesare’s lab contributed equally to this work. Their perseverance truly deserves immense recognition!
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Makoto T Hayashi @makotothayashi.bsky.social · 17/03/2025
🧵 1/10 Excited to share our latest study in @naturecomms.bsky.social "A CPC-shelterin-BTR axis regulates mitotic telomere deprotection" t.co/VypPsLBJCR
rdcu.be
A CPC-shelterin-BTR axis regulates mitotic telomere deprotection
Nature Communications - Here the authors reveal how telomeres signal mitotic stress. A key protein network alters their structure exposing telomere ends to signal mitotic stress, ultimately...
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