Fraction of total cellular ubiquitin pool that is estimated to be in the form of monoubiquitylation in HEK 293 cells

Range >60 %
Organism Human Homo sapiens
Reference Clague MJ, Heride C, Urbé S. The demographics of the ubiquitin system. Trends Cell Biol. 2015 Apr 20. pii: S0962-8924(15)00054-9. doi: 10.1016/j.tcb.2015.03.002. p.2 right column top paragraphPubMed ID25906909
Primary Source Kaiser, S.E. et al. (2011) Protein standard absolute quantification (PSAQ) method for the measurement of cellular ubiquitin pools. Nat. Methods 8, 691–696 doi: 10.1038/nmeth.1649.PubMed ID21743460
Comments p.2 right column top paragraph:"In HEK293 cells, more than 60% of the total cellular ubiquitin pool is estimated to be in the form of monoubiquitylation, about half of which is associated with a histone-enriched fraction [primary source]. The majority of this likely represents Ub-histone H2A (UbH2A), which is one of the most abundant cellular proteins (~1.7 × 10^7 copies per cell, HeLa). In many mammalian cell types, ~15% of H2A is monoubiquitylated, except during mitosis, when ubiquitin is quantitatively removed in a highly coordinated fashion [BNID 111556]."
Entered by Uri M
ID 111555