Genetic information is stored in cell nucleus on chromosomes. Eukaryotic chromosomes accommodate genes and large amounts of repetitive sequences, some of which are required for telomere, centromere and nucleolar organizer functions. Number of repeats varies greatly among plant species and , in combination with common polyploidization, is responsible for enormous nuclear genome size variation in plants. Furthermore, ratio of genes and repeats often determines overall 3D organization of chromosomes during interphase. Large genomes, such as our model species barley (Hordeum vulgare, 2n=2x=14, ca. 5 Gbp/1C) shows Rabl organization with polar localization of centromeres and telomeres. In contrast, smaller genomes, including our other main model Arabidopsis thaliana (2n=2x=10, ca. 150 Mbp/1C), do not maintain strict clustering of centromeres and have variable positioning of telomeres. In Arabidopsis, centromeres are attached to the nuclear periphery, while telomeres associate with nucleolus. Although described about century ago, molecular mechanisms determining such organizations and their consequences for e.g. nuclear division, DNA damage repair or homolog search remain unknown. We try understanding large scale plant genome organization during normal and DNA damage situations by focusing on the functions of Structural maintenance of chromosomes 5/6 (SMC5/6) complex. SMC5/6 works as intermolecular DNA linker, which ensures plant genome stability by so far unknown mechanism(s). Arabidopsis SMC5/6 mutants are not only DNA damage hypersensitive, but have many other not well understood phenotypes including sensitivity to DNA methylation inhibitors, defects during reproductive development and hyper-immune responses. Roles of SMC5/6 complex in maintaining genome functions in plants with large and Rabl-organized genomes are unknown.

Chromatin properties are determined epigenetically, i.e. by the DNA-interacting proteins and their modifications as well as the regulatory RNAs. Major chromatin states include heterochromatic, which is condensed, repeat-rich and transcriptionally repressed, while euchromatin is open and contains transcriptionally permissive modifications. Chromatin controls transcription in response to developmental and environmental signals and affect plant stress resistance and yield. Our group studies establishment, maintenance and functions of eu-and heterochromatin in plants during cell division and reproduction. This is of important because many plant products (proteins, sugars, oils, fibers) are obtained from plant reproductive tissues.

Vacancies


News

  • 2025-02-06: The meeting continued as Barley Away Days in Dunkeld, where Beata talked about the diversity of vernalization genes.
  • 2025-02-03: We met with the Barley Genome Net in Dundee! It was a meeting full of wonderful people and exciting science, also supported by Aleš, who gave a talk on parental conflict in barley.
  • 2025-01-10: Aleš na Beata are representing our group on PAG32 in San Diego! Aleš with a talk on DNA damage reponse and DNA-protein crosslink repair, and Beata will talk about natural variation of the vernalization pathway. Ejoy!
  • 2025-01-02: Happy New Year 2025 to everyone! We look forward to new adventures in the world of chromatin.
  • ​2025-01-02: A chapter on mapping-by-sequencing published in Methods for Plant Nucleus and Chromatin Studies (link). 
  • 2024-12-31: Jana, Shekoufeh and Jovanka left our group. We wish you a lot of success and a fresh start in 2025!
  • 2024-12-28: Last paper of 2024 published! A summary of the effects of cytidine analogs on plant development was published in the Journal of Experimental Botany (link).

POSTDOC WANTED! Our group is looking for a postdoc to study DNA-protein crosslink repair in the heterochromatin. Apply to work on uncharacterized Arabidopsis proteins identified in the HZE genetic screen. @czechacademy.bsky.social @apecinka.bsky.social @evadt.bsky.social

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— Chromatin organization and function (@pecinka-grp.bsky.social) April 22, 2025 at 11:28 AM

We celebrated @apecinka.bsky.social birthday last week. We had lots of fun playing badminton.

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— Chromatin organization and function (@pecinka-grp.bsky.social) April 13, 2025 at 7:43 PM

Former members

Serhii Mykhailyk (Postdoc 2024 - 2025)
 
Shekoufeh Ebrahimi (Postdoc 2024) Jovanka Vladejić (Ph.D. student 2018 - 2024)
Laboratory of Growth Regulators, IEB
 
Jana Zwyrtková (Postdoc 2021 - 2024)
Laboratory of Experimental Medicine, IMTM
Klára Procházková (Ph.D. student 2018 - 2023) Kashif Nawaz (Ph.D. student 2015 - 2019)
The Coral Symbiomics Lab, KAUST
Silvia Rinaldi (Ph.D. student 2021 - 2022) Jaroslav Filo (Ph.D. student 2022 - 2023)
Junior frontend developer, freelance
Pranav Pankaj Sahu (Postdoc 2017 - 2019)
Global Change Research Institute, CAS
  Beata Petrovská (Postdoc 2018 - 2019)
 
 
 

 

Projects

Publications