Density of integral membrane proteins

Range in human HeLa cell 4-5: in baby hamster kidney (BHK) fibroblast 3 integral membrane proteins/100nm^2
Organism Mammalian tissue culture cell
Reference Itzhak DN, Tyanova S, Cox J, Borner GH. Global, quantitative and dynamic mapping of protein subcellular localization. Elife. 2016 Jun 9 5. pii: e16950. doi: 10.7554/eLife.16950. p.9 top paragraphPubMed ID27278775
Primary Source Quinn P, Griffiths G, Warren G. Density of newly synthesized plasma membrane proteins in intracellular membranes II. Biochemical studies. J Cell Biol. 1984 Jun98(6):2142-7.PubMed ID6563038
Method Abstract: "[Investigators] have developed and applied Dynamic Organellar Maps, a proteomic method that allows global mapping of protein translocation events. [They] initially used maps statically to generate a database with localization and absolute copy number information for over 8,700 proteins from HeLa cells, approaching comprehensive coverage. All major organelles were resolved, with exceptional prediction accuracy (estimated at >92%). Combining spatial and abundance information yielded an unprecedented quantitative view of HeLa cell anatomy and organellar composition, at the protein level. [They] subsequently demonstrated the dynamic capabilities of the approach by capturing translocation events following EGF [epidermal growth factor] stimulation, which [they] integrated into a quantitative model." Primary source abstract: "Using two independent methods, incorporation of radioactive amino-acid and quantitative immunoblotting, [investigators] have determined that the rate of synthesis of each of the Semliki Forest virus (SFV) proteins in infected baby hamster kidney (BHK) cells is 1.2×10^5 copies/cell/min."
Comments P.9 top paragraph: "This predominance probably reflects the adaptation of HeLa cells for fast nutrient uptake to support rapid growth. Supporting this view, all plasma membrane transporters combined (40 million copies) contribute approximately 25% of the total compartment protein mass. Other integral membrane proteins (such as adhesion and signalling receptors) contribute ∼30 million copies. Assuming a cell surface area of ∼1,600 μm^2 typical of adherent HeLa cells (Fisher and Cooper, 1967 BNID 103718) yields an estimated density of 4-5 integral membrane proteins per 100 nm^2, in excellent agreement with a previous biochemically derived estimate of 3 for baby hamster kidney (BHK) fibroblasts (primary source)."
Entered by Uri M
ID 112707