Fig. 2

Genetic and biochemical findings. A Pedigree of the family investigated. Electropherogram showing the CHKB nucleotide substitutions detected in our patient and segregation analysis in his unaffected parents. B Transcript analysis of CHKB in patient’s muscle. Electropherograms show the sequences of RT-PCR amplicons obtained before (left) and after (right) subcloning. Subcloning experiment confirmed the partial intronic retention in CHKB ORF in patient’s muscle. C Sequence electropherograms of the intronic region between CHKB exons 3 and 4 and subcloning experiments confirming the the presence of a small deletion. D Western blot analysis of Mitofusin 2 (MFN2) and dynamin-related protein 1 (DRP1) protein levels in muscle samples from patient and controls. Actin levels were used as reference. E Graph showing respiratory chain enzymatic activities in Patient’s muscle compared to control levels assessed through spectrophotometric analysis (experiment in duplicate). Values are normalized to citrate synthetase (CS) activity and expressed as pmol/min/mg protein. F Western blot analysis of representative subunits of mitochondrial respiratory chain. No difference was observed between patients’ and control muscle samples. Actina and porin (VDAC) levels were used as reference