Mark Peifer (He, him)
@peiferlabunc.bsky.social
Cell adhesion, cytoskeletal regulation, Wnt signaling & wherever science leads us + wildflowers & my own idiosyncratic views. First gen college grad
Diversity, equity & Inclusion are core American Values
https://peiferlab.web.unc.edu
Diversity, equity & Inclusion are core American Values
https://peiferlab.web.unc.edu
This is VERY COOL!
So happy to announce our new preprint, “A geothermal amoeba sets a new upper temperature limit for eukaryotes.” We cultured a novel amoeba from Lassen Volcanic NP (CA, USA) that divides at 63°C (145°F) 🔥 - a new record for euk growth!
#protistsonsky 🧵
#protistsonsky 🧵
November 25, 2025 at 9:47 PM
This is VERY COOL!
Reposted by Mark Peifer (He, him)
EXCLUSIVE: US presidential envoy Steve Witkoff advised Russia on how to pitch Ukraine plans to Trump, in audio files reviewed by Bloomberg
Witkoff Advised Russia on How to Pitch Ukraine Plan to Trump
US presidential envoy Steve Witkoff, fresh from the triumph of the Gaza peace deal, held a phone call last month with a senior Kremlin official to suggest they work together on a similar plan for Ukraine — and that Vladimir Putin should raise it with Donald Trump.
bloom.bg
November 25, 2025 at 7:52 PM
EXCLUSIVE: US presidential envoy Steve Witkoff advised Russia on how to pitch Ukraine plans to Trump, in audio files reviewed by Bloomberg
Reposted by Mark Peifer (He, him)
Three things about the Witkoff tapes:
1) It appears Western intelligence services have decided to let Witkoff (and Trump) know they have recordings of their traitorous conversations w/Russia.
2) This Ukraine "deal" was all Witkoff's idea.
3) Congressional leaders should demand he be fired.
1) It appears Western intelligence services have decided to let Witkoff (and Trump) know they have recordings of their traitorous conversations w/Russia.
2) This Ukraine "deal" was all Witkoff's idea.
3) Congressional leaders should demand he be fired.
EXCLUSIVE: US presidential envoy Steve Witkoff advised Russia on how to pitch Ukraine plans to Trump, in audio files reviewed by Bloomberg
Witkoff Advised Russia on How to Pitch Ukraine Plan to Trump
US presidential envoy Steve Witkoff, fresh from the triumph of the Gaza peace deal, held a phone call last month with a senior Kremlin official to suggest they work together on a similar plan for Ukraine — and that Vladimir Putin should raise it with Donald Trump.
bloom.bg
November 25, 2025 at 8:40 PM
Three things about the Witkoff tapes:
1) It appears Western intelligence services have decided to let Witkoff (and Trump) know they have recordings of their traitorous conversations w/Russia.
2) This Ukraine "deal" was all Witkoff's idea.
3) Congressional leaders should demand he be fired.
1) It appears Western intelligence services have decided to let Witkoff (and Trump) know they have recordings of their traitorous conversations w/Russia.
2) This Ukraine "deal" was all Witkoff's idea.
3) Congressional leaders should demand he be fired.
Reposted by Mark Peifer (He, him)
Thanks to the tireless efforts of the Break the Bonds NC Coalition, our state government has divested the State Pension Fund from all $6.4M Israeli government bonds! breakthebondsnc.org
Send a letter of thanks and appreciation to Governor Josh Stein: actionnetwork.org/letters/gove... #NCpol
Send a letter of thanks and appreciation to Governor Josh Stein: actionnetwork.org/letters/gove... #NCpol
Governor Stein: Our state has taken a historic and important step
The Break the Bonds NC Coalition is thrilled to announce that North Carolina has divested the full $6.4M of Israeli government bonds from the State Pension Fund. Thank you for your participation in th...
actionnetwork.org
November 25, 2025 at 9:18 PM
Reposted by Mark Peifer (He, him)
Thanks to the tireless efforts of the Break the Bonds NC Coalition, our state government has divested the State Pension Fund from all $6.4M Israeli government bonds! breakthebondsnc.org
Send a letter of thanks and appreciation to Governor Josh Stein: actionnetwork.org/letters/gove... #NCpol
Send a letter of thanks and appreciation to Governor Josh Stein: actionnetwork.org/letters/gove... #NCpol
Governor Stein: Our state has taken a historic and important step
The Break the Bonds NC Coalition is thrilled to announce that North Carolina has divested the full $6.4M of Israeli government bonds from the State Pension Fund. Thank you for your participation in th...
actionnetwork.org
November 25, 2025 at 9:17 PM
Thanks to the tireless efforts of the Break the Bonds NC Coalition, our state government has divested the State Pension Fund from all $6.4M Israeli government bonds! breakthebondsnc.org
Send a letter of thanks and appreciation to Governor Josh Stein: actionnetwork.org/letters/gove... #NCpol
Send a letter of thanks and appreciation to Governor Josh Stein: actionnetwork.org/letters/gove... #NCpol
Reposted by Mark Peifer (He, him)
November 25, 2025 at 8:41 PM
Reposted by Mark Peifer (He, him)
Impeach, convict, remove.
And if our current leaders won’t do it, they need to step aside for people who will.
And if our current leaders won’t do it, they need to step aside for people who will.
November 25, 2025 at 6:46 PM
Impeach, convict, remove.
And if our current leaders won’t do it, they need to step aside for people who will.
And if our current leaders won’t do it, they need to step aside for people who will.
Reposted by Mark Peifer (He, him)
#Sudan: We call on the RSF to protect health facilities and staff, following the death of a Ministry of Health colleague during a shooting at Zalingei hospital.
For the second time this year, we have withdrawn staff to ensure their safety.
ow.ly/O8VW50XxNcx
For the second time this year, we have withdrawn staff to ensure their safety.
ow.ly/O8VW50XxNcx
Sudan: MSF calls for protection of health facilities and staff after health worker killed | Doctors Without Borders / Médecins Sans Frontières (MSF ...
MSF calls for protection of health workers and facilities after a colleague was killed at Zalingei Hospital in Central Darfur, disrupting care.
ow.ly
November 25, 2025 at 8:43 PM
#Sudan: We call on the RSF to protect health facilities and staff, following the death of a Ministry of Health colleague during a shooting at Zalingei hospital.
For the second time this year, we have withdrawn staff to ensure their safety.
ow.ly/O8VW50XxNcx
For the second time this year, we have withdrawn staff to ensure their safety.
ow.ly/O8VW50XxNcx
Reposted by Mark Peifer (He, him)
We tracked the motility of 𝘐. 𝘤𝘢𝘴𝘤𝘢𝘥𝘦𝘯𝘴𝘪𝘴 across temp and found it is active up to 64°C (movie here), with most directed motion from 55-64°C🏃♀️! It seems to use the vermiform state to travel quickly and the amoebiform state to explore space.
November 25, 2025 at 8:22 PM
We tracked the motility of 𝘐. 𝘤𝘢𝘴𝘤𝘢𝘥𝘦𝘯𝘴𝘪𝘴 across temp and found it is active up to 64°C (movie here), with most directed motion from 55-64°C🏃♀️! It seems to use the vermiform state to travel quickly and the amoebiform state to explore space.
Reposted by Mark Peifer (He, him)
In 2023, we first sampled from a geothermal tributary at LVNP and using enrichment culturing, found an amoeba growing at high temp.
November 25, 2025 at 8:22 PM
In 2023, we first sampled from a geothermal tributary at LVNP and using enrichment culturing, found an amoeba growing at high temp.
Reposted by Mark Peifer (He, him)
While 𝘝. 𝘷𝘦𝘳𝘮𝘪𝘧𝘰𝘳𝘮𝘪𝘴 max temp is around 45°C, we found 𝘐. 𝘤𝘢𝘴𝘤𝘢𝘥𝘦𝘯𝘴𝘪𝘴 grows up to 63°C with optimal growth at 55-57°C🥵. We showed cellular replication via Ultrastructure Expansion Microscopy at 63°C. The previous limit for euks is 60°C!
November 25, 2025 at 8:22 PM
While 𝘝. 𝘷𝘦𝘳𝘮𝘪𝘧𝘰𝘳𝘮𝘪𝘴 max temp is around 45°C, we found 𝘐. 𝘤𝘢𝘴𝘤𝘢𝘥𝘦𝘯𝘴𝘪𝘴 grows up to 63°C with optimal growth at 55-57°C🥵. We showed cellular replication via Ultrastructure Expansion Microscopy at 63°C. The previous limit for euks is 60°C!
Reposted by Mark Peifer (He, him)
Check out that spindle 🤩🔥
At 63C, most eukaryotic cells would be busy exploding noisily, forget even trying to divide.
The microbial universe never ceases to astound 😍
Thanks for letting us be a tiny part of this! #ExpandThemAll
At 63C, most eukaryotic cells would be busy exploding noisily, forget even trying to divide.
The microbial universe never ceases to astound 😍
Thanks for letting us be a tiny part of this! #ExpandThemAll
While 𝘝. 𝘷𝘦𝘳𝘮𝘪𝘧𝘰𝘳𝘮𝘪𝘴 max temp is around 45°C, we found 𝘐. 𝘤𝘢𝘴𝘤𝘢𝘥𝘦𝘯𝘴𝘪𝘴 grows up to 63°C with optimal growth at 55-57°C🥵. We showed cellular replication via Ultrastructure Expansion Microscopy at 63°C. The previous limit for euks is 60°C!
November 25, 2025 at 8:30 PM
Check out that spindle 🤩🔥
At 63C, most eukaryotic cells would be busy exploding noisily, forget even trying to divide.
The microbial universe never ceases to astound 😍
Thanks for letting us be a tiny part of this! #ExpandThemAll
At 63C, most eukaryotic cells would be busy exploding noisily, forget even trying to divide.
The microbial universe never ceases to astound 😍
Thanks for letting us be a tiny part of this! #ExpandThemAll
Reposted by Mark Peifer (He, him)
Last bit to vote in the @genetics-gsa.bsky.social board of directors elections! I will note I'm the only candidate on the ballot who has won the GSA Corn Pun Trophy. genetics-gsa.org/2025-election/
November 25, 2025 at 8:01 PM
Last bit to vote in the @genetics-gsa.bsky.social board of directors elections! I will note I'm the only candidate on the ballot who has won the GSA Corn Pun Trophy. genetics-gsa.org/2025-election/
Reposted by Mark Peifer (He, him)
Louisiana Surgeon General Ralph Abraham has just been named as the principal deputy director at the CDC.
Abraham’s accomplishments include banning the health department from promoting vaccines and overseeing the concomitant explosion of whooping cough in the state, which has killed two babies.
Abraham’s accomplishments include banning the health department from promoting vaccines and overseeing the concomitant explosion of whooping cough in the state, which has killed two babies.
November 25, 2025 at 6:49 PM
Louisiana Surgeon General Ralph Abraham has just been named as the principal deputy director at the CDC.
Abraham’s accomplishments include banning the health department from promoting vaccines and overseeing the concomitant explosion of whooping cough in the state, which has killed two babies.
Abraham’s accomplishments include banning the health department from promoting vaccines and overseeing the concomitant explosion of whooping cough in the state, which has killed two babies.
Reposted by Mark Peifer (He, him)
Breaking News: The CDC quietly appointed Dr. Ralph Lee Abraham, who has been critical of vaccines, as its second in command. During the Covid pandemic, he promoted discredited treatments like ivermectin and, as Louisiana’s surgeon general, halted the state’s mass vaccination campaign.
C.D.C. Quietly Appoints Doctor Critical of Vaccines as Second in Command
During the Covid-19 pandemic, Dr. Ralph Lee Abraham promoted discredited treatments like ivermectin and, as Louisiana’s surgeon general, halted the state’s mass vaccination campaign.
trib.al
November 25, 2025 at 6:43 PM
Breaking News: The CDC quietly appointed Dr. Ralph Lee Abraham, who has been critical of vaccines, as its second in command. During the Covid pandemic, he promoted discredited treatments like ivermectin and, as Louisiana’s surgeon general, halted the state’s mass vaccination campaign.
Reposted by Mark Peifer (He, him)
We're steadily making our way through our list of Tennessee voters to make sure they know about the upcoming special election, and what's at stake for science and health.
We need your help! Join us to phonebank for Aftyn each evening (save Thanksgiving!) at 7pm ET. Sign up at tr.ee/final-sprint
We need your help! Join us to phonebank for Aftyn each evening (save Thanksgiving!) at 7pm ET. Sign up at tr.ee/final-sprint
November 25, 2025 at 7:00 PM
We're steadily making our way through our list of Tennessee voters to make sure they know about the upcoming special election, and what's at stake for science and health.
We need your help! Join us to phonebank for Aftyn each evening (save Thanksgiving!) at 7pm ET. Sign up at tr.ee/final-sprint
We need your help! Join us to phonebank for Aftyn each evening (save Thanksgiving!) at 7pm ET. Sign up at tr.ee/final-sprint
Reposted by Mark Peifer (He, him)
Our next Advocacy Town Hall meeting is on December 2! Hear updates from Capitol Hill, federal agencies, and science policy news. Meetings are virtual and open to the public. Reserve your spot now ➡️ buff.ly/6ZX3sWD
November 25, 2025 at 7:02 PM
Our next Advocacy Town Hall meeting is on December 2! Hear updates from Capitol Hill, federal agencies, and science policy news. Meetings are virtual and open to the public. Reserve your spot now ➡️ buff.ly/6ZX3sWD
Reposted by Mark Peifer (He, him)
Putting on my hat as @asn-amnat.bsky.social
ASN President for announcements, please share widely!!!
2. ASN Early Career Investigator awards are now open for application. Self-nominations okay! Due Jan 5
nam10.safelinks.protection.outlook.com?url=https%3A...
ASN President for announcements, please share widely!!!
2. ASN Early Career Investigator awards are now open for application. Self-nominations okay! Due Jan 5
nam10.safelinks.protection.outlook.com?url=https%3A...
Applications for the 2026 ASN Early Career Investigator Award
<p>Nominations/Applications for the 2026 Early Career Investigator Award are <strong>due January 5, 2026</strong></p><br/>
nam10.safelinks.protection.outlook.com
November 25, 2025 at 5:59 PM
Putting on my hat as @asn-amnat.bsky.social
ASN President for announcements, please share widely!!!
2. ASN Early Career Investigator awards are now open for application. Self-nominations okay! Due Jan 5
nam10.safelinks.protection.outlook.com?url=https%3A...
ASN President for announcements, please share widely!!!
2. ASN Early Career Investigator awards are now open for application. Self-nominations okay! Due Jan 5
nam10.safelinks.protection.outlook.com?url=https%3A...
Reposted by Mark Peifer (He, him)
Putting on my hat as @asn-amnat.bsky.social ASN President for announcements, please share widely!!!
3. The ASN Conceptual Unification of Biological Sciences award is for a late career investigator www.amnat.org/announcement...
3. The ASN Conceptual Unification of Biological Sciences award is for a late career investigator www.amnat.org/announcement...
Nominations for the ASN Award for Distinguished Achievement in the Conceptual Unification of the Biological Sciences
<p>The Conceptual Unification award is given annually and honors a senior but active investigator who is making fundamental contributions to the Society's goals in promoting the conceptual unifica...
www.amnat.org
November 25, 2025 at 6:59 PM
Putting on my hat as @asn-amnat.bsky.social ASN President for announcements, please share widely!!!
3. The ASN Conceptual Unification of Biological Sciences award is for a late career investigator www.amnat.org/announcement...
3. The ASN Conceptual Unification of Biological Sciences award is for a late career investigator www.amnat.org/announcement...
Reposted by Mark Peifer (He, him)
A stunning visual of Chicago's 20-year death gap, mapped on the L, via @myersjustinc.bsky.social @chicago.suntimes.com. Here's what residents & community leaders are doing to close this gap: tinyurl.com/47r2vcj5 @wbez.org @chjreportinghealth.bsky.social @watchdogdiva.bsky.social @kffhealthnews.org
November 21, 2025 at 5:31 PM
A stunning visual of Chicago's 20-year death gap, mapped on the L, via @myersjustinc.bsky.social @chicago.suntimes.com. Here's what residents & community leaders are doing to close this gap: tinyurl.com/47r2vcj5 @wbez.org @chjreportinghealth.bsky.social @watchdogdiva.bsky.social @kffhealthnews.org
Reposted by Mark Peifer (He, him)
Putting on my hat as @asn-amnat.bsky.social ASN President for a minute for a string of announcements, please share widely!!!
1. Student research awards are open for applications, to fund research expenses for 10 graduate students ($2000 each)
nam10.safelinks.protection.outlook.com?url=https%3A...
1. Student research awards are open for applications, to fund research expenses for 10 graduate students ($2000 each)
nam10.safelinks.protection.outlook.com?url=https%3A...
Student Research Award
<p>The ASN Student Research Awards support research by student members that advances the goals of the society: the conceptual unification of ecology, evolution, and behavior. Each award consists of a ...
nam10.safelinks.protection.outlook.com
November 25, 2025 at 5:55 PM
Putting on my hat as @asn-amnat.bsky.social ASN President for a minute for a string of announcements, please share widely!!!
1. Student research awards are open for applications, to fund research expenses for 10 graduate students ($2000 each)
nam10.safelinks.protection.outlook.com?url=https%3A...
1. Student research awards are open for applications, to fund research expenses for 10 graduate students ($2000 each)
nam10.safelinks.protection.outlook.com?url=https%3A...
Reposted by Mark Peifer (He, him)
Yang, Kong, Liu et al. report that homocysteine, an intermediate in methionine-cysteine #metabolism and the cause of the life-threatening disease #homocystinuria, disrupts lysosomal functions by binding to and homocysteinylating V-ATPase. rupress.org/jcb/article/...
#lysosomes
#lysosomes
November 25, 2025 at 7:00 PM
Yang, Kong, Liu et al. report that homocysteine, an intermediate in methionine-cysteine #metabolism and the cause of the life-threatening disease #homocystinuria, disrupts lysosomal functions by binding to and homocysteinylating V-ATPase. rupress.org/jcb/article/...
#lysosomes
#lysosomes
Reposted by Mark Peifer (He, him)
Like @peiferlabunc.bsky.social I am thankful for schools that have made it easy to submit letters of reference for their graduate applicants (although a single letter on Interfolio should suffice for this). I am also not a fan of schools that make things more complicated than they need to be.
November 25, 2025 at 6:54 PM
Like @peiferlabunc.bsky.social I am thankful for schools that have made it easy to submit letters of reference for their graduate applicants (although a single letter on Interfolio should suffice for this). I am also not a fan of schools that make things more complicated than they need to be.
Reposted by Mark Peifer (He, him)
Things I currently think you should be considering in your proposals. Although this thread will be NIH-centric, my guess is that some of this applies to NSF, etc. Much is synthesized from public information. Much of this is what we've advised all along, just with, um, more emphasis.
Here we go:
Here we go:
November 25, 2025 at 3:27 PM
Things I currently think you should be considering in your proposals. Although this thread will be NIH-centric, my guess is that some of this applies to NSF, etc. Much is synthesized from public information. Much of this is what we've advised all along, just with, um, more emphasis.
Here we go:
Here we go:
Reposted by Mark Peifer (He, him)
How do Xylem-Pole-Pericycle cells decide between forming a new Lateral Root or contributing to cambium formation & secondary growth?
Cytokinins facilitate cambium development & reduce LR potency, shaping the entire root architecture!
@apmahonen.bsky.social
doi.org/10.1016/j.mo...
#PlantScience
Cytokinins facilitate cambium development & reduce LR potency, shaping the entire root architecture!
@apmahonen.bsky.social
doi.org/10.1016/j.mo...
#PlantScience
November 25, 2025 at 2:29 PM
How do Xylem-Pole-Pericycle cells decide between forming a new Lateral Root or contributing to cambium formation & secondary growth?
Cytokinins facilitate cambium development & reduce LR potency, shaping the entire root architecture!
@apmahonen.bsky.social
doi.org/10.1016/j.mo...
#PlantScience
Cytokinins facilitate cambium development & reduce LR potency, shaping the entire root architecture!
@apmahonen.bsky.social
doi.org/10.1016/j.mo...
#PlantScience