Abstract
In Brassica, alloplasmic lines which display cytoplasmic male sterility (CMS) were selected and established by combining the nucleus from B. rapa with the cytoplasm from Diplotaxis muralis. To investigate the molecular mechanism for the influence of nucleus on cytoplasm, we examined the expression of mitochondrial genes (coxI, coxII, coxIII, atpA, atp6, atp9, cob, nad3, nad6, and nad9) in the leaves of euplasmic and alloplasmic lines of B. rapa and D. muralis. Greater accumulations of mRNA for mitochondrial genes were detected in alloplasmic lines of B. rapa compared to D. muralis. On the other hand, reduced accumulations of mRNA for mitochondrial gene was detected in the young buds of alloplasmic lines of B. rapa compared to D. muralis (Yamasaki et al. 1998). Alterations in patterns for transcription of mitochondrial genes lead to the impairment of mitochondrial function, thus may cause some defects in alloplasmic lines of B. rapa.
