Hello Satyajit Ghosh

Yes, you are right. They could be nuclear stress granules which is an indication of cellular stress. These stress granules are subcellular compartments that modulate the response to endogenous and environmental signals to control cell survival. Stress granules assemble rapidly in response to stress stimuli and disappear slowly after the stress is reduced or completely removed.

Have you observed cytoplasmic stress granules? Because both nucleoli and cytoplasmic stress granules have established roles in the cellular stress response. They cooperate to determine cell fate when the cellular homeostasis is disrupted.

You may refer to the articles attached below for more information.

Article Nucleoli and Stress Granules: Connecting Distant Relatives

Article Nuclear stress granules: The awakening of a sleeping beauty?

Best.

Thank you Malcolm Nobre for your answer. The granules are only located inside nucleus and not in the cytoplasm.

Hi,

Stress granules (SGs) are cytoplasmic foci of RNA and proteins that form in cells under stress.

Black dots are chromatin. Their number depends on the degree of packing of chromatin. "

Euchromatin and Heterochromatin

"The DNA in the nucleus exists in two forms that reflect the level of activity of the cell. Heterochromatin appears as small, darkly staining, irregular particles scattered throughout the nucleus or accumulated adjacent to the nuclear envelope. Euchromatin is dispersed and not readily stainable. Euchromatin is prevalent in cells that are active in the transcription of many of their genes while heterochromatin is most abundant in cells that are less active or not active. "

http://www.medcell.org/histology/cell_lab/euchromatin_and_heterochromatin.php

https://www.biomadam.com/euchromatin-vs-heterochromatin

"During the interphase of the cell cycle, chromatin is loosely packed, for cell division, chromosomes must be densely packed (condensed) in order to allow their proper separation into daughter cells." The appearance of the nucleus depends on the degree of chromatin packing, which changes during the cell cycle.

https://www.sciencedirect.com/science/article/pii/B9780128033951000058

Justyna Augustyniak

Thank you Justyna Augustyniak.