uq 9  (MedChemExpress)

Journal: eLife

Article Title: Alternative splicing of coq-2 controls the levels of rhodoquinone in animals

doi: 10.7554/eLife.56376

Figure Lengend Snippet: ( A ) In aerobic metabolism, ubiquinone (UQ) shuttles electrons in the ETC from Complex I (CI; yellow box) and quinone-coupled dehydrogenases (QDHs), such as Complex II. These electrons are ultimately transferred to oxygen. In anaerobic metabolism, rhodoquinone (RQ) reverses electron flow in QDHs and facilitates an early exit of electrons from the ETC onto anaerobic electron acceptors (Ae - A), such as fumarate. ( B ) The RQ biosynthetic pathway in C. elegans requires L -tryptophan, a precursor in the kynurenine pathway. L -Trptophan is transformed into 3-hydroxyanthranilic acid (3HA) in four steps. It is proposed that 3HA is a substrate for COQ-2, producing 3-hydroxy-5-nonaprenylanthranilic acid (NHA), where n=9. The transformation of NHA to RQ requires several shared proteins from the UQ biosynthetic pathway. ( C ) Eukaryotes can use either p -aminobenzoic acid (pABA) or 4-hydroxybenzoic acid (4HB) as precursors to UQ. Prenylation is facilitated by Coq2 to form 3-hexaprenyl-4-hydroxybenzoic acid (HHB) or 3-hexaprenyl-4-aminobenzoic acid (HAB), where n = varies between species. Further functionalization of these intermediates occurs through a Coq synthome ( Coq 3–Coq9 and Coq11) to yield UQ.

Article Snippet: The UQ 3 standard was synthesized at Gonzaga University , the RQ 9 standard was isolated by preparative chromatography from A. suum lipid extracts ( ) and the UQ 9 standard was purchased (Sigma-Aldrich, St. Louis, MO).

Techniques: Transformation Assay

Journal: eLife

Article Title: Alternative splicing of coq-2 controls the levels of rhodoquinone in animals

doi: 10.7554/eLife.56376

Figure Lengend Snippet: ( A ) Mutant strains were generated in C. elegans by deletion of exon 6a ( coq-2 ∆6a) or exon 6e ( coq-2 ∆6e). ( B ) Deletion of exon 6a from the coq-2 gene significantly increased the level of RQ 9 (p=0.013) and significantly decreased UQ 9 (p<0.001) compared to the N2 control. By contrast, the deletion of exon 6e decreased RQ 9 to a negligible level (p<0.001) and slightly increased the level of UQ 9 (p=0.130) compared to N2. Statistically significant increases and decreases with respect to N2 levels are denoted with ★ and ◊, respectively; error bars reflect standard deviation where N = 4. ( C ) Deletion of coq-2 exon 6e affects the ability of worms to survive extended KCN treatment. Wild-type ( N2 ) and coq-2 mutant L1 worms were exposed to 200 µM KCN for 15 hr. KCN was then diluted 6-fold and worm movement was measured over 3 hr to track recovery from KCN exposure (see Materials and methods). Worms without exon 6e could not survive extended treatment with KCN while deletion of exon 6a had little effect on KCN survival. Cyanide titration is shown in . Curves show the mean of four biological replicates and error bars are standard errors of the mean.

Article Snippet: The UQ 3 standard was synthesized at Gonzaga University , the RQ 9 standard was isolated by preparative chromatography from A. suum lipid extracts ( ) and the UQ 9 standard was purchased (Sigma-Aldrich, St. Louis, MO).

Techniques: Mutagenesis, Generated, Standard Deviation, Titration