Fig. 5

Cell-type-specific differential expression of SDHs mRNAs and proteins. A Diagram showing the involvement of the SDH protein complex (CII) in both the electron transport system and TCA cycle. The ribbon representation of the crystal structure of Escherichia coli SDH, analogous to the mammalian mitochondrial respiratory complex II, was based on Protein Data Bank (PDB) entry: 1NEK [109]. Molecular graphics were prepared using UCSF Chimera package [110]. B Agarose gel showing four subunits of SDH complex (SDHA, SDHB, SDHC, SDHD) and their specific PCR products simultaneously co-amplified by multiplex RT-PCR. WT: wild-type (parental), KO: CAMKK2 deleted HEK293 and HepG2 cells, L: molecular weight ladder. C, D The ImageJ-based plot profile of the SDH-specific bands presented in Figure B showing relative band intensities (arbitrary units) corresponding to respective gene expression level. The green space-filled areas indicate the relatively increased/decreased SDHB expression corresponding to an increased/decreased area under the curve in the respective cell types. E–H SDHA and SDHB fold change normalized to SDHC. Data presented as Mean ± SEM. N = 3 replicates from 2 independent experiments. Statistical significance from one-way ANOVA followed by multiple comparisons test. Ns: not significant (P > 0.05). I, J Scatter plots showing SDHA, SDHB and SDHC protein levels in parental (WT) and CAMKK2 deleted HEK293 (clone A5, 10) and HepG2 (clone C1, D1) cell clones. The SDHB was detected using mouse monoclonal anti-SDHB antibody obtained from Santa Cruz Biotechnology Inc. (Table 1)