@raphmercier.bsky.social
#Meiosis4ever. #ChromosomeBiology. Max Planck for Plant Breeding Research.
Congrats to Dipesh, the driver of this story. And thanks to all the contributors and in particular the collaborators Jelle Van Leene and Geert De Jaeger (amazing IP ms) and the best of all Raphaels @raphguerois.bsky.social for the structure predictions and analysis
November 7, 2025 at 9:18 PM
Congrats to Dipesh, the driver of this story. And thanks to all the contributors and in particular the collaborators Jelle Van Leene and Geert De Jaeger (amazing IP ms) and the best of all Raphaels @raphguerois.bsky.social for the structure predictions and analysis
Idee de sujet:
www.nature.com/articles/d41...
www.nature.com/articles/d41...
Is this the future of food? 'Sexless' seeds that could transform farming
Scientists are tinkering with plant genes to create crops that seed their own clones, with a host of benefits for farmers.
www.nature.com
September 8, 2025 at 4:03 PM
Idee de sujet:
www.nature.com/articles/d41...
www.nature.com/articles/d41...
Reposted
Six more years—plus a lot of blood, sweat, and tears—later, we are thrilled to finally share it: a cytological framework of female meiosis in Arabidopsis!
www.biorxiv.org/content/10.1...
www.biorxiv.org/content/10.1...
A cytological framework of female meiosis in Arabidopsis
Female and male meiosis often differ in many aspects, such as their duration and the frequency as well as the positioning of crossovers. However, studying female meiosis is often very challenging and ...
www.biorxiv.org
August 25, 2025 at 4:30 PM
Six more years—plus a lot of blood, sweat, and tears—later, we are thrilled to finally share it: a cytological framework of female meiosis in Arabidopsis!
www.biorxiv.org/content/10.1...
www.biorxiv.org/content/10.1...
Thank you and congrats to all contributors in Versailles @ijpb-versaillescly.bsky.social and Cologne @mpipz.bsky.social and in particular to Dipesh Singh, Alexander Mahland, Rigel Salinas, Joiselle Fernandes and Qichao Lian.
August 25, 2025 at 7:54 AM
Thank you and congrats to all contributors in Versailles @ijpb-versaillescly.bsky.social and Cologne @mpipz.bsky.social and in particular to Dipesh Singh, Alexander Mahland, Rigel Salinas, Joiselle Fernandes and Qichao Lian.
The identification of the very conserved CTF18, SGO2 and SPF2 as suppressors of centromere-proximal crossovers highlights the importance of cohesin turnover in this process and opens up new possibilities for plant breeding. Much more in the paper : www.biorxiv.org/content/10.1...
Unlocking meiotic crossovers near plant centromeres
Crossovers (COs) ensure proper chromosome segregation during meiosis and generate genetic diversity. COs are non-uniformly distributed along chromosomes and almost universally suppressed in centromere...
www.biorxiv.org
August 25, 2025 at 7:54 AM
The identification of the very conserved CTF18, SGO2 and SPF2 as suppressors of centromere-proximal crossovers highlights the importance of cohesin turnover in this process and opens up new possibilities for plant breeding. Much more in the paper : www.biorxiv.org/content/10.1...
and guess what, some did! The cohesion regulators CTF18 and SGO2, and the deSUMOylase SPF2 actively limit centromere proximal crossover. Their mutation allows both the formation of crossover where they were completely absent in the wild-type, and enhance their frequency where they were rare!
two women are sitting next to each other and one is pointing at the camera
ALT: two women are sitting next to each other and one is pointing at the camera
media.tenor.com
August 25, 2025 at 7:54 AM
and guess what, some did! The cohesion regulators CTF18 and SGO2, and the deSUMOylase SPF2 actively limit centromere proximal crossover. Their mutation allows both the formation of crossover where they were completely absent in the wild-type, and enhance their frequency where they were rare!
We reasoned that the changes in the organization of the centromere-proximal region that affect kinetochore orientation in the identified mutants (see above and the first preprint) may also affect crossover formation near centromeres.
a close up of a woman 's face with a triangle and a mathematical formula .
ALT: a close up of a woman 's face with a triangle and a mathematical formula .
media.tenor.com
August 25, 2025 at 7:54 AM
We reasoned that the changes in the organization of the centromere-proximal region that affect kinetochore orientation in the identified mutants (see above and the first preprint) may also affect crossover formation near centromeres.
But there are genes in these regions, which are thus innacissible to recombinatiion. This creates a significant bottleneck for plant breeding.
a close up of a person 's hand touching a plant in a field .
ALT: a close up of a person 's hand touching a plant in a field .
media.tenor.com
August 25, 2025 at 7:54 AM
But there are genes in these regions, which are thus innacissible to recombinatiion. This creates a significant bottleneck for plant breeding.
An now the SECOND story.
Meiotic crossover shuffle genetic information. But, they are non-uniformly distributed along chromosomes and almost universally suppressed in centromere-proximal regions. How crossover are prevented next to centromere is unclear.
Meiotic crossover shuffle genetic information. But, they are non-uniformly distributed along chromosomes and almost universally suppressed in centromere-proximal regions. How crossover are prevented next to centromere is unclear.
a little girl wearing a shirt that says " til to " is eating a snack
ALT: a little girl wearing a shirt that says " til to " is eating a snack
media.tenor.com
August 25, 2025 at 7:54 AM
An now the SECOND story.
Meiotic crossover shuffle genetic information. But, they are non-uniformly distributed along chromosomes and almost universally suppressed in centromere-proximal regions. How crossover are prevented next to centromere is unclear.
Meiotic crossover shuffle genetic information. But, they are non-uniformly distributed along chromosomes and almost universally suppressed in centromere-proximal regions. How crossover are prevented next to centromere is unclear.
Our findings demonstrate that cohesion establishment and protection, kinetochore, and deSUMOylation enforce monopolar orientation in plants. This support a cohesion-driven model of kinetochore orientation at meiosis I that is conserved across kingdoms. Take a look: www.biorxiv.org/content/10.1...
Monopolar orientation of kinetochores at meiosis is enforced by COHESINS and their regulators, CENP-C, and the deSUMOylase SPF2
The first division of meiosis is unique in its capacity to halve the ploidy of the future gametes. To this end, one key innovation compared to mitosis is the monopolar orientation of the pairs of sist...
www.biorxiv.org
August 25, 2025 at 7:54 AM
Our findings demonstrate that cohesion establishment and protection, kinetochore, and deSUMOylation enforce monopolar orientation in plants. This support a cohesion-driven model of kinetochore orientation at meiosis I that is conserved across kingdoms. Take a look: www.biorxiv.org/content/10.1...
We show that monopolar orientation involves all four cohesin subunits (REC8, SCC3, SMC1, SMC3), the cohesion establishment factors CTF18 and DCC1, and the cohesin protectors SGO1/2 and PANS1, the inner kinetochore protein CENP-C, and the desumoylase SPF2.
August 25, 2025 at 7:54 AM
We show that monopolar orientation involves all four cohesin subunits (REC8, SCC3, SMC1, SMC3), the cohesion establishment factors CTF18 and DCC1, and the cohesin protectors SGO1/2 and PANS1, the inner kinetochore protein CENP-C, and the desumoylase SPF2.