Mitotic Spindle Attachment to the Holocentric Chromosomes of Cuscuta europaea Does Not Correlate With the Distribution of CENH3 Chromatin

0532441 - BC 2021 RIV CH eng J - Journal Article
Oliveira, Ludmila - Neumann, Pavel - Jang, Tae-Soo - Klemme, Sonja - Schubert, J. - Koblížková, Andrea - Houben, A. - Macas, Jiří
Mitotic Spindle Attachment to the Holocentric Chromosomes of Cuscuta europaea Does Not Correlate With the Distribution of CENH3 Chromatin.
Frontiers in Plant Science. Roč. 10, January (2020), č. článku 1799. ISSN 1664-462X. E-ISSN 1664-462X
R&D Projects: GA ČR(CZ) GA17-09750S
Institutional support: RVO:60077344
Keywords : centromere * kinetochore * cenh3 * holocentric chromosomes * repetitive DNA analysis * satellite DNA * Cuscuta
OECD category: Genetics and heredity (medical genetics to be 3)
Impact factor: 5.754, year: 2020
Method of publishing: Open access
https://www.frontiersin.org/articles/10.3389/fpls.2019.01799/full

The centromere is the region on a chromosome where the kinetochore assembles and spindle microtubules attach during mitosis and meiosis. In the vast majority of eukaryotes, the centromere position is determined epigenetically by the presence of the centromere-specific histone H3 variant CENH3. In species with monocentric chromosomes, CENH3 is confined to a single chromosomal region corresponding to the primary constriction on metaphase chromosomes. By contrast, in holocentrics, CENH3 (and thus centromere activity) is distributed along the entire chromosome length. Here, we report a unique pattern of CENH3 distribution in the holocentric plant Cuscuta europaea. This species expressed two major variants of CENH3, both of which were deposited into one to three discrete regions per chromosome, whereas the rest of the chromatin appeared to be devoid of CENH3. The two CENH3 variants fully co-localized, and their immunodetection signals overlapped with the positions of DAPI-positive heterochromatic bands containing the highly amplified satellite repeat CUS-TR24. This CENH3 distribution pattern contrasted with the distribution of the mitotic spindle microtubules, which attached at uniform density along the entire chromosome length. This distribution of spindle attachment sites proves the holocentric nature of C. europaea chromosomes and also suggests that, in this species, CENH3 either lost its function or acts in parallel to an additional CENH3-free mechanism of kinetochore positioning.
Permanent Link: http://hdl.handle.net/11104/0310933