Respiratory complex I and embryo development

Complex I (CI) is a large membranous mitochondrial enzyme that serves as the major entry point for electrons from NADH into the respiratory chain. The CI enzyme is considered to be conserved between different organisms, but plant CI includes an extra 'eggshaped' module - the gamma-carbonic anhydrase domain - and a paper by Cordoba et al. in this issue of Journal of Experimental Botany (pages 1589-1603) indicates that its functions are required during Arabidopsis embryogenesis.