Both Conifer II and Gnetales are characterized by a high frequency of ancient mitochondrial gene transfer to the nuclear genome

Mitochondrial gene transfer/loss is common in land plants, but the fate of missing mitochondrial genes has received little attention. The gene content of gymnosperm mitochondria varies greatly, supplying an ideal system for studying the evolutionary fate of missing mitochondrial genes. In this work, we studied the tempo and pattern of mitochondrial gene loss/transfer in gymnosperms represented by all 13 families and 19 genera using high-throughput sequencing of both DNA and cDNA.