2012 Volume 77 Issue 2 Pages 123-129
Cardiolipin (CL) is widely distributed in various prokaryotes and eukaryotes as a membrane phospholipid. In eukaryotes, it is localized in the inner membrane and at the contact sites between the inner and outer membranes of mitochondria. CL is suggested to be involved in many mitochondrial functions. We previously identified the CLS gene for CL synthase in Arabidopsis thaliana and showed it to be a useful tool for understanding the physiological roles of CL in higher plants. In this study, we isolated homozygous cls mutants (cls-1 and cls-2) of A. thaliana, in which the CLS gene was disrupted by T-DNA insertion, by observing the development of embryos obtained after self-fertilization of heterozygous cls mutants. Both embryogenesis and growth of the homozygous cls mutants were substantially retarded relative to wild type, and additional phenotypes were observed, namely slow root growth, an abnormal veining pattern in cotyledons, and a low yield of seed production. The delayed embryogenesis and growth of homozygous cls mutants were recovered by introduction of CLS into the mutants. These findings demonstrate that CLS plays important roles in development of A. thaliana, presumably due to the biosynthesis of CL in the mitochondria.
