Huge congratulations to the fantastic team work: Catarina Pedro, @ltovini.bsky.social, @catarinapeneda.bsky.social and Mia

11/
Preprint here 👇
www.biorxiv.org/content/10.6...
Would love feedback!

10/
Our work links two fields that often don’t talk enough:
🧬 Mitosis
🧬 Transcription regulation
and highlights how their coordination preserves cellular integrity

9/
We further show that:
Disrupting this timing → nucleolar fragmentation in interphase
👉 Mitotic transcription timing has consequences beyond mitosis

8/
Importantly, this challenges the idea that transcription simply resumes passively as cells exit mitosis.
Instead, reactivation is actively restrained and timed

7/
This leads to:
• early rRNA synthesis
• premature recruitment of nucleolar components
👉 Transcription turns ON too early

6/
But here’s the unexpected part 👇
Loss of TTF2 triggers premature RNA Polymerase I activation during anaphase

5/
As expected:
Loss of TTF2 → retention of chromatin-associated transcripts in metaphase
(mainly RNA Pol II–derived)
✔️ Consistent with its known role in transcriptional clearance

4/
Using nascent RNA labelling + polymerase-specific perturbations, we tracked transcription dynamics across mitosis in:
• human embryonic stem cells
• HeLa cells

3/
We focused on TTF2, a factor known to remove RNA Polymerase II transcripts at mitotic entry.
But what happens later—during transcriptional reactivation?

2/
During mitosis, transcription is globally shut down.
As cells exit mitosis, transcription must be reactivated—precisely and in the right order.
How this timing is controlled remains poorly understood.

🧵1/
Excited to share our new preprint!
We uncover a new layer of control in how cells restart transcription after mitosis.
👉 TTF2 prevents premature rRNA transcription during mitotic exit
(www.biorxiv.org/content/10.6...)

11/
Preprint here 👇
(www.biorxiv.org/content/10.6...)
Would love feedback!

10/
Our work links two fields that often don’t talk enough:
🧬 Mitosis
🧬 Transcription regulation
and highlights how their coordination preserves cellular integrity

9/
We further show that:
Disrupting this timing → nucleolar fragmentation in interphase
👉 Mitotic transcription timing has consequences beyond mitosis

8/
Importantly, this challenges the idea that transcription simply resumes passively as cells exit mitosis.
Instead, reactivation is actively restrained and timed

7/
This leads to:
• early rRNA synthesis
• premature recruitment of nucleolar components
👉 Transcription turns ON too early

6/
But here’s the unexpected part 👇
Loss of TTF2 triggers premature RNA Polymerase I activation during anaphase

5/
As expected:
Loss of TTF2 → retention of chromatin-associated transcripts in metaphase
(mainly RNA Pol II–derived)
✔️ Consistent with its known role in transcriptional clearance

4/
Using nascent RNA labeling + polymerase-specific perturbations,
we tracked transcription dynamics across mitosis in:
• human embryonic stem cells
• HeLa cells

3/
We focused on TTF2, a factor known to remove RNA Polymerase II transcripts at mitotic entry.
But what happens later—during transcriptional reactivation?

Many thanks for sharing, Paulo! ;)

Thank you!!!

Thank you for the compliment. Full transparency: the cartoon was AI-assisted — but it required serious scientific mentoring 😂 Convincing ChatGPT that anaphase = sister chromatids, not X-shaped chromosomes was a multi-cycle process. Peer review works, even for AI!

Thank you for the compliment. Full transparency: the cartoon was AI-assisted — but it required serious scientific mentoring 😂 Convincing ChatGPT that anaphase = sister chromatids, not X-shaped chromosomes was a multi-cycle process. Peer review works, even for AI!

Congratulations, @ltovini.bsky.social! What a journey this has been! This story would not exist without your determination, resilience, and scientific imagination. You kept pushing when things were difficult and turned complexity into clarity. I am super proud of you!!

Thanks for the nice words! Indeed... yeast could be seen as an exception (as they keep transcription mostly on) but not all over :D also needs to be off at some sites. And there are even more interesting things on Pol I that will come on another upcoming ms. Stay tuned ;)

6/ 🧬 Check out the full preprint: www.biorxiv.org/content/10.6...

5/ This means that mitotic transcription isn’t just a passive consequence of cell cycle stage — it actively threatens genome stability when not properly regulated.

4/ The result? When transcription isn’t cleared, sister chromatid resolution is impaired — a critical step needed to ensure faithful chromosome segregation in anaphase.