Tonni Andersen
@tonnigrubeandersen.bsky.social
MPG group leader and AvH fellow with interests in development, physiology and CLSM. I need to know how 🌱 communicate with environment. privately: huge cat-fan
Six years ago, I started at the MPIPZ with a head full of ideas. What a journey. I’m thrilled to share that, from Jan 2026, I will be moving to Zurich as a chaired associate professor at the University of Zurich.
A new chapter, and plenty of roots still to grow. Can’t wait for the adventure ahead!
A new chapter, and plenty of roots still to grow. Can’t wait for the adventure ahead!
September 1, 2025 at 7:25 AM
Six years ago, I started at the MPIPZ with a head full of ideas. What a journey. I’m thrilled to share that, from Jan 2026, I will be moving to Zurich as a chaired associate professor at the University of Zurich.
A new chapter, and plenty of roots still to grow. Can’t wait for the adventure ahead!
A new chapter, and plenty of roots still to grow. Can’t wait for the adventure ahead!
For all the people at #2025ISMPMI. Make sure to check the amazingly cool work of @pascal-krohn.bsky.social on fungal infection in the periderm. It is on Thursday in poster session 2 P-446
July 14, 2025 at 7:56 AM
For all the people at #2025ISMPMI. Make sure to check the amazingly cool work of @pascal-krohn.bsky.social on fungal infection in the periderm. It is on Thursday in poster session 2 P-446
Congrats to all co-winners! ☺️
July 2, 2025 at 9:10 AM
Congrats to all co-winners! ☺️
Dipping some feet in the lake!
July 1, 2025 at 12:28 PM
Dipping some feet in the lake!
@esmmicrobes.bsky.social come to Poster 17 and check out the cool project from the amazing @liobarueger.bsky.social on how Arabidopsis natural variation contributes to microbe-dependent N-use efficiency in agricultural soil (p.s. She loves protists)
June 17, 2025 at 8:20 AM
@esmmicrobes.bsky.social come to Poster 17 and check out the cool project from the amazing @liobarueger.bsky.social on how Arabidopsis natural variation contributes to microbe-dependent N-use efficiency in agricultural soil (p.s. She loves protists)
We made this summary model that also integrates MYB68 into periderm and middle cortex formation, which is an essential part of our sister manuscript headed by Lauras group, so a continuation is soon to come. (you can check the preprint here: www.biorxiv.org/content/10.1... )
June 9, 2025 at 7:02 AM
We made this summary model that also integrates MYB68 into periderm and middle cortex formation, which is an essential part of our sister manuscript headed by Lauras group, so a continuation is soon to come. (you can check the preprint here: www.biorxiv.org/content/10.1... )
There is a lot more super cool findings in this paper, including specific localization of MYB68 to phloem-pole associated endodermis (PPE), which may explain its role as a passage cell inhibitor, although we don't know the mechanism... yet..
June 9, 2025 at 7:02 AM
There is a lot more super cool findings in this paper, including specific localization of MYB68 to phloem-pole associated endodermis (PPE), which may explain its role as a passage cell inhibitor, although we don't know the mechanism... yet..
Since Leonie is unstoppable, she decided to look deeper into this using Fluorescent in-situ Hybridization techniques to visualize mRNA. She found direct evidence that several K-transporters including HAK5 is expressed in passage cells:
June 9, 2025 at 7:02 AM
Since Leonie is unstoppable, she decided to look deeper into this using Fluorescent in-situ Hybridization techniques to visualize mRNA. She found direct evidence that several K-transporters including HAK5 is expressed in passage cells:
These included some surprises that you can read in the paper, but also genes associated with gibberelin and, excitingly, also cation transport!!
June 9, 2025 at 7:02 AM
These included some surprises that you can read in the paper, but also genes associated with gibberelin and, excitingly, also cation transport!!
We realized that this could be used to identify what these elusive cells do, and we embarked on a transcriptional adventure to figure out which genes correlate with the passage cell behavior under standard and under cytokinin-treatment in the myb68 KO roots. This way, we got ~300 new markers!
June 9, 2025 at 7:02 AM
We realized that this could be used to identify what these elusive cells do, and we embarked on a transcriptional adventure to figure out which genes correlate with the passage cell behavior under standard and under cytokinin-treatment in the myb68 KO roots. This way, we got ~300 new markers!
She thereby realized MYB68 may be related to passage cell formation and not directly suberization - a finding that was confirmed by measurement of the passage cell marker PHO1;H3, which was strongly increased in the endodermis of myb68 KO roots
June 9, 2025 at 7:02 AM
She thereby realized MYB68 may be related to passage cell formation and not directly suberization - a finding that was confirmed by measurement of the passage cell marker PHO1;H3, which was strongly increased in the endodermis of myb68 KO roots
What was super cool is the the XPE hosts so-called "passage cells" that are sensitive to low amounts of cytokinin, which represses their formation. Leonie found that the pattern of myb68 KO root suberization could be reversed when germinated on the artificial cytokinin BAP. a very exciting hint!
June 9, 2025 at 7:02 AM
What was super cool is the the XPE hosts so-called "passage cells" that are sensitive to low amounts of cytokinin, which represses their formation. Leonie found that the pattern of myb68 KO root suberization could be reversed when germinated on the artificial cytokinin BAP. a very exciting hint!
Leonie went all-in and described this change in suberin patterning - down to single cells along the entire root! - it took about 2 months of imaging to get this data and describe the pattern with such detail, but turns out that the effect is spatially restricted to certain cell files along the root
June 9, 2025 at 7:02 AM
Leonie went all-in and described this change in suberin patterning - down to single cells along the entire root! - it took about 2 months of imaging to get this data and describe the pattern with such detail, but turns out that the effect is spatially restricted to certain cell files along the root
This turned out to be a strong decrease in suberization of specifically the xylem pole-associated endodermis (XPE). A very exciting pattern, which may explain why suberin is a dynamic process that is always hard to describe correctly.
June 9, 2025 at 7:02 AM
This turned out to be a strong decrease in suberization of specifically the xylem pole-associated endodermis (XPE). A very exciting pattern, which may explain why suberin is a dynamic process that is always hard to describe correctly.
Leonie wanted to find new regulators involved in a process called "suberization" - where the endodermal cells in the root close to minimize transport of molecules. She discovered that MYB68 - which is related to the Casparian strip regulator, had a peculiar pattern of suberin deposition when KOed:
June 9, 2025 at 7:02 AM
Leonie wanted to find new regulators involved in a process called "suberization" - where the endodermal cells in the root close to minimize transport of molecules. She discovered that MYB68 - which is related to the Casparian strip regulator, had a peculiar pattern of suberin deposition when KOed:
Manga vs real-life
May 11, 2025 at 3:58 PM
Manga vs real-life
Thank you @lauraragni.bsky.social for a great time in Freiburg! Was great to catch up with @elkebarbez.bsky.social @hartman-plantlab.com and many other!
May 10, 2025 at 1:15 PM
Thank you @lauraragni.bsky.social for a great time in Freiburg! Was great to catch up with @elkebarbez.bsky.social @hartman-plantlab.com and many other!
Never knew how many souls are trapped inside a pancake - I might need an exorcist! (Works best with sound)
April 19, 2025 at 7:59 PM
Never knew how many souls are trapped inside a pancake - I might need an exorcist! (Works best with sound)
Im just adding also a picture of MALDI-MSI showing sugar distribution, because this is simply too cool to be true!
March 21, 2025 at 5:53 AM
Im just adding also a picture of MALDI-MSI showing sugar distribution, because this is simply too cool to be true!
Through an amazing collaboration with researchers at University of Copenhagen: @nbjarnholt.bsky.social ,Christoph Crocoll and Daniel Persson, we were able to image nutrients and metabolites inside nodules with and without formation of barriers!
March 21, 2025 at 5:53 AM
Through an amazing collaboration with researchers at University of Copenhagen: @nbjarnholt.bsky.social ,Christoph Crocoll and Daniel Persson, we were able to image nutrients and metabolites inside nodules with and without formation of barriers!
Moreover, and even more excitingly, Defeng was able to describe that nodules themselves form apoplastic barriers via Casparian strips and that this is crucial for nodule function.
March 21, 2025 at 5:53 AM
Moreover, and even more excitingly, Defeng was able to describe that nodules themselves form apoplastic barriers via Casparian strips and that this is crucial for nodule function.
Defeng now set out on a quest to identify what the underlying reason could be. He found that plants without barriers not only have trouble establishing the association with bacteria, they also struggle to establish nodules and if they finally form, the nodules are super inefficient and delayed.
March 21, 2025 at 5:53 AM
Defeng now set out on a quest to identify what the underlying reason could be. He found that plants without barriers not only have trouble establishing the association with bacteria, they also struggle to establish nodules and if they finally form, the nodules are super inefficient and delayed.
This allowed us to ask about the role of barriers in symbiotic plant-microbe interactions and in particular N-fixation, which is extremely important for these plants. To our great surprise, this physical feature is crucial, as plants without barriers have trouble forming functional nodules.
March 21, 2025 at 5:53 AM
This allowed us to ask about the role of barriers in symbiotic plant-microbe interactions and in particular N-fixation, which is extremely important for these plants. To our great surprise, this physical feature is crucial, as plants without barriers have trouble forming functional nodules.
This work started with Defeng asking the question, what is known about root barriers – in particular the Casparian strip in Lotus japonius? – turns out we could identify mutants that do not have barriers in this cool model plant, which can form N-fixing nodules on their roots.
March 21, 2025 at 5:53 AM
This work started with Defeng asking the question, what is known about root barriers – in particular the Casparian strip in Lotus japonius? – turns out we could identify mutants that do not have barriers in this cool model plant, which can form N-fixing nodules on their roots.
As a PI, I make Pie for my group on pi-day (3/14)! 😆
March 14, 2025 at 7:17 AM
As a PI, I make Pie for my group on pi-day (3/14)! 😆