Mitochondrial ATP synthase activity assay
Mitochondrial ATP synthase activity was measured by a colorimetric assay
using the ATPase activity assay kit (D799641-0050, Shenggong, China)
following the manufacturer’s instructions. The seedlings were cultured
on 1/2 MS medium for 2 weeks and leaves were collected for determination
of ATP synthase activity. To approximately 0.1g of tissue, 1mL of
reagent I was added, and the mixture was homogenized in an ice bath,
centrifuged at 8000g for 10min at 4°C and the supernatant was used as
the ATP synthase extract. Sample processing was according to the
manufacturer’s protocol. Finally, ATP synthase activity was determined
by measuring the OD at 660 nm. Each experiment was performed with three
biological samples, each with three technical replicates.