Arrangement of nuclear structures is not transmitted through mitosis but is identical in sister cells.
Although it is well known that chromosomes are non-randomly organized during interphase, it is not completely clear whether higher-order chromatin structure is transmitted from mother to daughter cells. Therefore, we addressed the question of how chromatin is rearranged during interphase and whether heterochromatin pattern is transmitted after mitosis. We additionally tested the similarity of chromatin arrangement in sister interphase nuclei. We noticed a very active cell rotation during interphase, especially when histone hyperacetylation was induced or transcription was inhibited. This natural phenomenon can influence the analysis of nuclear arrangement. Using photoconversion of Dendra2-tagged core histone H4 we showed that the distribution of chromatin in daughter interphase nuclei differed from that in mother cells. Similarly, the nuclear distribution of heterochromatin protein 1β (HP1β) was not completely identical in mother and daughter cells. However, identity between mother and daughter cells was in many cases evidenced by nucleolar composition. Moreover, morphology of nucleoli, HP1β protein, Cajal bodies, chromosome territories, and gene transcripts were identical in sister cell nuclei. We conclude that the arrangement of interphase chromatin is not transmitted through mitosis, but the nuclear pattern is identical in naturally synchronized sister cells. It is also necessary to take into account the possibility that cell rotation and the degree of chromatin condensation during functionally specific cell cycle phases might influence our view of nuclear architecture.
Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Královopolská 135, CZ-612 65 Brno, Czech Republic.
Darya Yu
DY
Orlova
Lenka
L
Stixová
Stanislav
S
Kozubek
Hinco J
HJ
Gierman
Gabriela
G
Šustáčková
Andrei V
AV
Chernyshev
Ruslan N
RN
Medvedev
Soňa
S
Legartová
Rogier
R
Versteeg
Pavel
P
Matula
Roman
R
Stoklasa
Eva
E
Bártová
D000818:Animals; D002460:Cell Line; D002466:Cell Nucleolus / Q000187:drug effects / Q000235:genetics / Q000648:ultrastructure*; D000090266:Chromobox Protein Homolog 5; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism; D020541:Coiled Bodies / Q000187:drug effects / Q000235:genetics / Q000648:ultrastructure*; D003609:Dactinomycin / Q000494:pharmacology; D005456:Fluorescent Dyes; D006570:Heterochromatin / Q000187:drug effects / Q000235:genetics* / Q000648:ultrastructure; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology; D006657:Histones / Q000235:genetics / Q000378:metabolism; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology; D007399:Interphase / Q000187:drug effects / Q000235:genetics*; D051379:Mice; D008856:Microscopy, Fluorescence; D008938:Mitosis / Q000187:drug effects / Q000235:genetics*; D055668:Photochemical Processes; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D012333:RNA, Messenger / Q000096:biosynthesis
C000715593:CBX1 protein, human; C096188:Cbx1 protein, mouse; D002868:Chromosomal Proteins, Non-Histone; D005456:Fluorescent Dyes; D006570:Heterochromatin; D056572:Histone Deacetylase Inhibitors; D006657:Histones; D006877:Hydroxamic Acids; D011500:Protein Synthesis Inhibitors; D012333:RNA, Messenger; D000090266:Chromobox Protein Homolog 5; D003609:Dactinomycin; C012589:trichostatin A