Table I

Biological half-lives of individual proteins in U937 cells determined by calculations from protein amounts and synthesis rates in comparison to pulse-chase experiments

FI, as determined by fluorimaging; PI, as determined by phosphoimaging. S.E. values of protein amounts, synthesis rates, and biological half-lives determined from pulse-chase experiments were obtained from three individual experiments, and error values of calculated biological half-lives were calculated combining the error rates of protein amounts and synthesis rates, respectively.

ProteinSwissProt accession no.ng of protein per 106 cells (FI)Synthesis in ng/h per 106 cells (PI)Theoretical time required for synthesisCalculated biological half-lifeAutoradiograph intensity recovered after pulse-chase vs. controlBiological half-life determined from pulse-chase
h h % h
hsp70P08107118 ± 117.2 ± 0.6216.418.1 ± 3.343.520.0 ± 1.6
CalreticulinP27797460 ± 6218.8 ± 0.2824.566.5 ± 1977.565.3 ± 7.2
StathminP16949280 ± 1314.3 ± 0.8419.628.2 ± 3.056.328.9 ± 2.2
PGMP18669166 ± 108.2 ± 0.3720.232.4 ± 3.663.536.6 ± 3.6
eIF-5AP10159150 ± 177.0 ± 0.4121.437.5 ± 6.560.833.4 ± 4.4
TIMP00938345 ± 3717.1 ± 1.220.231.0 ± 5.455.528.3 ± 2.2
ER-60P27797136 ± 298.1 ± 1.516.019.2 ± 6.745.621.2 ± 2.3
EF-2P13639224 ± 1611.4 ± 1.119.628.3 ± 4.752.826.0 ± 3.1
GST-πP09211540 ± 2325.4 ± 1.621.236.4 ± 3.866.040.0 ± 2.8
hsc70P11142915 ± 7148.4 ± 6.118.925.6 ± 5.247.222.2 ± 2.4
grp75P38646295 ± 2814.5 ± 1.920.331.6 ± 7.256.128.8 ± 3.0
grp78P11021325 ± 4916.5 ± 1.819.728.8 ± 7.561.634.4 ± 4.2
TM30P07226132 ± 256.2 ± 1.021.337.0 ± 1360.833.4 ± 2.9
hsp60Q9POX2320 ± 1915.7 ± 1.120.431.8 ± 4.260.032.5 ± 1.9
rho GDI 2P52566185 ± 159.3 ± 0.919.929.2 ± 5.255.328.0 ± 1.6