Fig. 4
In vivo pulsed SILAC reveals enhanced Lys-6 labeling for assembly factors and OXPHOS complex subunits. a Schematic overview of Lys-6 administration for 14 days followed by the ProFit assay. Experiments were conducted in biological quadruplicates (n = 4). Theoretical MS SILAC pairs indicate proteins with slow and fast turnover. b Density plot of Lys-6 incorporation into different fiber types from the soleus (Sol), EDL (E), Gast (G) and tibialis anterior (T). Type I soleus fibers (depicted in blue) exhibited the highest Lys-6 incorporation rate. c Boxplot analysis of Lys-6 incorporation into different MYH isoforms in the soleus, EDL, TA, and Gast muscle groups. d Selected proteins with high, intermediate and low Lys-6 incorporation into newly synthesized proteins. e Selected proteins with different Lys-6 incorporation between slow (soleus) and fast muscle fiber types (EDL, Gast, TA). f–k Scatter plots for different muscle fiber types from distinct muscle groups. Red dots represent proteins with significantly different Lys-6 (H)-to-Lys-0 (L) ratios (one-sample t test; p value < 0.05 and abs. difference > 1.5). l Map of OXPHOS proteins and assembly factors and their Lys-6 incorporation rates. Complex I modules are indicated by PD, PP; Q and N. m Lys-6 incorporation rates for complex IV subunits and complex IV assembly factors (AF) in the skeletal muscle (SM), liver (L), heart (H), and brain (B) tissue in biological triplicates (n = 3)