The oocytes had a euchromatin
nucleus at the germinal vesicle stage and the granulosa and theca cell nuclei showed peripheral aggregations of heterochromatin.
Furthermore, the use of aniline blue staining revealed the granulosa cells in the control culture showed the round nuclei of euchromatin
in the centre of their cytoplasm.
The eukaryotic DNA consists of transcriptionally active DNA called Euchromatin
and transcriptionaly incompetent DNA that is Heterochromatin.
Unmethylated or hypomethylated DNA participates to the formation of an open (or active or unrepressed) euchromatin
structure which allows the high levels of gene expression needed for ESCs to differentiate in various lineages.
, widely interspersed retrotransposons demonstrate nonrandom and TE-sequence-specific chromosomal clustering  (present work, Figure 2), indicating the TEs' impact on the genome architecture and diversification.
Generally, the complexes catalyze the formation of repressive epigenetic marks at histone 3 such as H3K27 and H3K9, a hallmark of heterochromatic regions, and the permissive H3K4 mark, which is associated with the formation of euchromatin
A heterozygous microdeletion at chromosome 9q34.3 overlapping the euchromatin
histone methyltransferase 1 (EHMT1) gene accounts for more than 75% of cases, and the remainder are associated with a heterozygous intragenic pathogenic variant in the EHMT1 gene [1, 2].
The protein concentrates in euchromatin
regions that correspond to a highly transcribed part of the chromosome.
OLs of the isolated mice displayed increased euchromatin
and decreased heterochromatin, indicating a less differentiated state .
Posttranscriptional histone modifications (PTM) play a critical role in chromatin structure acquiring two configurations, one more closed (heterochromatin) and inactive and another less compact (euchromatin
) and associated with active gene transcription.
We pioneered the concept that [NAD.sup.+] redox and intermediary metabolism sensors sirtuin1 (SIRT1) and sirtuin6 (SIRT6) epigenetically reprogram the universal attributes of resistance to tolerance in monocytes by shifting glycolysis and glucose oxidation high energy use to the low energy state lipolysis by generating silent heterochromatin at selective sets of immune and metabolism fueling gene sets (TNF[alpha]) [4, 5] and maintaining open euchromatin
at reciprocally functioning gene sets [6-8].
The nuclei are characterized by patches of euchromatin
and heterochromatin regions with the latter usually occupying the periphery of the organelle.