- high-resolution terminology - matching measurements at high-resolution
F-junction
Description
The F-junction is a junction for convergent electron flow in the electron transfer system (ETS) from fatty acids (type F substrates) through fatty acyl CoA dehydrogenase (reduced form FADH2) to electron transferring flavoprotein (CETF), and further transfer through the Q-junction to Complex III (CIII). The concept of the F-junction and N-junction provides a basis for defining categories of SUIT protocols. Fatty acid oxidation (FAO) not only depends on electron transfer through the F-junction (which is typically rate-limiting) but simultaneously generates NADH and thus depends on N-junction throughput. Hence FAO can be inhibited completely by inhibition of Complex I (CI). In addition and independent of this source of NADH, the type N substrate malate is required as a co-substrate for FAO in mt-preparations, since accumulation of AcetylCo inhibits FAO in the absence of malate. Malate is oxidized in a reaction catalyzed by malate dehydrogenase to oxaloacetate (yielding NADH), which then stimulates the entry of AcetylCo into the TCA cycle catalyzed by citrate synthase.
Reference: Gnaiger 2014 MitoPathways
MitoPedia methods: Respirometry
MitoPedia O2k and high-resolution respirometry: "SUIT protocol" is not in the list (O2k hardware, DatLab, Oroboros QM, O2k-Open Support, O2k-Respirometry, O2k-FluoRespirometry) of allowed values for the "MitoPedia O2k and high-resolution respirometry" property.
SUIT protocol"SUIT protocol" is not in the list (O2k hardware, DatLab, Oroboros QM, O2k-Open Support, O2k-Respirometry, O2k-FluoRespirometry) of allowed values for the "MitoPedia O2k and high-resolution respirometry" property.
Contributed by Gnaiger E 2016-02-12
