Figure 4.

Organelle proteomics. (A) Western blot of human HepG2 homogenate (H), crude mitochondrial fraction (M), and Percoll-purified mitochondria (P) probed with an antibody against cytochrome c, a marker for mitochondria, and calreticulin, a marker for contamination by endoplasmic reticulum. Two different loading volumes (5 and 10 μl) were used for each sample. (B) Representative tandem mass spectrum showing y-ion and b-ion series along with the deduced peptide sequence. (C) The predicted LRPPRC (GenBank accession no. XP_031527.3) amino acid sequence with high-scoring peptides, identified by organelle proteomics, marked in red.