Pečinka Group

A longstanding aim of our group is to understand genome organization and functions in plants. We study how DNA is assembled into chromatin and chromosomes and how do the chromatin factors control plant development, stress resistance and genome stability.
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.
News
  • 2023-05-04: Klara won a silver medal from the Dean of the Faculty of Natural Sciences of Palacky University. Congratulations.
  • 2023-04-19: Wonderful group field trip with a treasure hunt and pizza. It was fun for everyone.
  • 2023-03-27: Klára successfully defended her Ph.D. Big congratulations Dr. Klara Prochazkova!
  • ​2023-03-27: Fruitful discussions with Dr. Miriam Szurman Zubrzycka from the University of Silesia in Katowice about barley and more.
  • 2022-01-27: Eva's paper on SMC5/6-dependent SUMOylation in Arabidopsis DNA repair is published in the Plant Cell. Congratulations! (link)
  • 2022-01-27: Exciting work on Anna on non-Rabl chromosome organization in specific barley tissues is published in JXB. Congratulations! (link)
  • 2022-11-29: Great visit of Götz Hensel's lab and discussions with many colleagues on barley at the HHU/CEPLAS in Düsseldorf (foto
  • 2022-10-13: J. Doležel and A. Pečinka from IEB speak at the Conference on genome editing for food safety and crop improvement (link) organized by Czech Academy of Sciences in Prague, CZ
  • 2022-09-29: Eva Dvořák Tomaštíková speaks at the Genome organisation by SMC complexes conference in Edinburgh, UK (link)
  • 2022-09-19: Elixir Cytogenomics meeting in Třešť. Nice encounter with many colleagues interested in genome biology from CZ and DE. Also great teambuilding via football tennis and orientation running.
  • 2022-09-12 to 15: Green4Good IV meeting of the European Federation of Biotechnology in Olomouc. Top science and lots of great discussions.

Publications