Ndufa3 Conditional Knockout mouse models

Human NDUFA3 corresponds to mouse Ndufa3, encoding the small B9 subunit that inserts into the membrane arm of complex I close to the mtDNA-encoded ND1 subunit, where it participates in the earliest membrane arm assembly module and helps stabilize the region forming the quinone-binding interface. Compared with better characterized accessory subunits, human pathogenic variants are rare, so its biology rests largely on assembly studies showing that loss impairs formation of the ND1-containing intermediate and lowers mature holoenzyme, producing an isolated complex I defect without affecting other respiratory complexes. Given this, a constitutive or conditional null is the informative first allele, and inducible deletion in adult tissues distinguishes developmental from maintenance requirements, while a humanized knockin becomes valuable when candidate variants of uncertain significance need functional adjudication. No paralogous subunit substitutes. Pair the allele with endpoints tracking assembly intermediates by BN-PAGE and complexome profiling, alongside rotenone-sensitive oxygen consumption, ATP synthesis rates, and tissue markers of energetic stress.

A floxed Ndufa3 allele paired with Cre gives spatial control that whole body knockouts cannot offer. People use it to separate developmental roles from adult homeostasis, to model somatic mutations, and to match disease that begins in one organ.