Table 1.

Commonalities and differences in the key processes of mammalian nuclear removal; Comparison of known nuclear degradation processes and signalling pathways activated in keratinocytes, lens fibre cells and erythroblasts. A tick denotes that process or phenomenon is active in that cell type, a cross denotes that it is not, and – not determined in that cell type.

		Keratinocytes	Lens fibre cells	Erythroblasts
Morphological changes	Rounding	✗ 42,43	✓ 9,10	✓ 31,32
	Decrease in size	✓ 42	✓ 9,10	✓ 31,32
	Indentations	✓ 42,43	✓ 11	—
	Karyolysis	—	✓ 9,10	✓ 34,35 Through openings
	Nuclear extrusion	✗ 42,43	✗ 9,10	✓ 30,31
Changes in nuclear organisation	DNA condensation	—	✓ 12	✓ 36
	HDAC required	—	—	✓ 36
	Sub-nuclear compartments	✓ 42	✓ 12	✓ 33
Breakdown of the nuclear envelope	Lamina degradation	✓ 45	✓ 12	—
	Phosph. of Lamin A/C	✓ 45	✓ 20	—
	Nuclear openings	—	—	✓ 34
DNA degradation	Enzymatic DNA degradation	✓ 44,47	✓ 16	✓ 28In macrophages
	TUNEL staining	✗ 43	✓ 12,13	—
	DNase expression ↑	✓ 47	✓ 13	—
	DNase(s) required	✓ 44,47	✓ 15,16	✓ 28
Proteolysis	Ubiquitin proteasome pathway required	—	✓ 21	✓ 64,65
Apoptosis	Apoptotic caspases required	✗ 43,57	✗ 17	✓ 34 Only for openings
Autophagy	ATG5 required	✗ 51,52	✗ 11,18	✗ 18
	Perinuclear autophagosomes	✓ 43,56	✗ 11,18	—
	Perinuclear lysosomes	—	✓ 19,20	—
	Nucleophagy	✓ 43	—	—
Signalling	mTORC1 signalling ↓	✓ 43,45,58	✓ 22	—
	CDK1 signalling ↑	—	✓ 20	—
	AKT1 phosph. of Lamin A/C	✓ 45	—	—
	Intracellular calcium ↑	✓ 4	✓ 26	✓ 40