Abstract
In plant vegetative cell, mitochondria are usually small grain-shaped. On the other hand, it was reported that unusually shaped, giant mitochondria (large cup-shaped or long, stretched rod-shaped) appeared in the egg cells of geranium and maize. However, studies on the egg cell mitochondria were reported only in geranium and maize. In this study, to characterize the mitochondria of rice egg cell, we isolated unfertilized egg cells of rice by means of non-enzymatic, manual dissection, and observed the egg cell mitochondria and mitochondrial DNA (mtDNA) simultaneously. These observations showed that the egg cell mitochondria of rice were small grain-shaped, unlike geranium and maize. Quantitative-PCR reveals that an egg cell of rice contained at least 15-fold mtDNA compared with a rice leaf protoplast.
