We are looking for a colleague to join us at RWTH Aachen University:

🌱 Full Professor in Stress Resilience of Plants (W3 tenured)

📌What are we looking for? Someone working with us strategically at the interface of plant biology/ physiology/ resilience

#academicjobs #facultyjobs #PlantJobs

1/4

Repeat evolution seems to take off, e.g. 5S rDNA:

- very low, scattered abundance with barely intact genes in Hydnora

- extreme amplification in sister genus Prosopanche (> 15 % of genome; is this the highest value ever seen?)

- extreme sequence divergence

---> we wonder...

(4/6)

Quick insight -- You see the two sister genera

1) Hydnora with 8 sp.:
a lot of gypsy retrotransposons; nearly no 5S rDNA; similar compositions

2) Prosopanche with 3 sp.:
very different compositions; high amplification of an En/Spm DNA transposon (P. bonacinae) and the 5S (P. panguanensis)

(3/6)

🧬How do repeatomes (genomes) evolve, if plants are fully dependent on the host?

📚 Read here: www.biorxiv.org/content/10.1...

🌱We look into the repeat landscapes of 11 species from an iconic holoparasitic plant family, the Hydnoraceae.

(1/6)

🧬Interested in #RepetitiveDNA and #TransposableElements?

🌱Visiting the #PlantScience mega-congress #IBC2024 in Madrid?

Let's meet, let's greet, let's connect! And let us know, if you plan to join, so that we can count you in (forms.gle/sDmBA1GScN2Q...).

I think as an artist, it is over, if you do a clear copy of an artist style... in this case, Mucha. The AI can do copies incredibly well, you need a unique element ...

Attached are some AI images that I had asked in Mucha style ... the AI has mastered it perfectly, i think

Summarizing, each gene pool has its own repeat composition and chromosomal makeup. This goes a long way regarding different evolutionary routes and the underlying biology of the taxa ...

9/14

And then, there is the secondary gene pool that does not play by the rules:

All chromosomes have different make-ups and hence are more or less unique. There are also no clearly dominant satellite DNAs. Due to their patchy appearance, we call them "patchwork chromosomes".

8/14

A bit similar is the tertiary gene pool:

Only few satellite DNAs are amplified and these are the building blocks of the chromosomes in one of three ways.

7/14

So what does this mean?

In the primary beet gene pool, two satellite DNAs are highly amplified and homogenized. Those two are the building blocks of all beet chromosomes in the primary gene pool.

6/14

Of course, as a fast-evolving genome component, satellite DNAs are different between species. But they are vastly different between gene pools. Here, the bubble area marks abundance in different beets.

5/14

Now, we look at the beet repeat fraction:

As so often, larger genome sizes can be explained with more repetitive DNAs (A). Also, more DNA --> more retrotransposons (B). But some fractions (C; D), are not so easily explained. We look more deeply into the satellite DNAs (D)...

4/14

📊To make sure that we cover genetic variability & that there is indeed no base chromosome variation, we sampled widely:

- across all three gene pools
- across the two botanical sister genera Beta & Patellifolia
- across all sections and major species, including polyploids

2/14

🌱All beets have the same base chromosome number. But despite the chromosomal stability, crossing between gene pools is difficult.

🧬We find that repetitive DNAs evolved differently in the gene pools, marking speciation and crossing boundaries.

doi.org/10.1111/tpj....

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🌱🧬We are grateful that Nii-Ayi Ankrah from KNUST (Ghana) was able to join the lab to provide insight into the surprising chromosomal variability of kenaf breeding lines.

Now, you can read about this work in our preprint:
doi.org/10.1101/2023...

The preprint provides a map through the test cases, including repeats, eccDNA and even linked and separated rDNA. Even more info and the corresponding code, you will find at Ludwig's github:

github.com/crimBubble/r...

🧬💚New preprint out, led by Ludwig and our fresh MSc graduate Kristin: Reliable repetitiveDNA consensus sequences from short reads -- do they exist and how can you do them? Is it worth in times of ONT/PacBio? Can newer genome assembly tools help?

🧬🖥️📈find out: doi.org/10.1101/2023...

Like many of you, I gaze at a new, bright, blue sky and say #HiSciSky 💙!

I am a biologist & plant genomes and chromosomes are my specialty. I am fascinated by the large, repetitive part of the genome that underlies much of the variability that we can observe.

Just look at the apple 🍏🍎!

🌿🌲🌾
Do you enjoy looking at plant chromosomes, but do not know how? Do not worry!
🔎🔬
Sònia Garcia and me worked for two years to bring together exactly 100 authors for a Plant Cytogenetics and Cytogenomics protocol collection!
🧬💚

link.springer.com/book/10.1007...