LOSS OF ALL NDH GENES AS DETERMINED BY SEQUENCING THE ENTIRE CHLOROPLAST GENOME OF THE BLACK PINE PINUS-THUNBERGII

The complete nucleotide sequence (119,707 bp) of the black pine (Pinus thunbergii) chloroplast genome has been determined, it contains 4 rRN A genes and 32 tRNA genes. To our knowledge, the tRNA(Pro) (GGG) gene has not been found in any other chloroplast genome analyzed. Sixty-one genes encoding proteins and 11 conserved open reading frames are also found. Extensive rearrangements are apparent in tbe chloroplast genom e relative to those of other land plants. The most striking feature is the loss of all 11 functional genes (ndh genes) for subunits of a put ative NADH dehydrogenase that are found in the chloroplast genomes of angiosperms and a bryophyte. Four ndh genes were completely lost and t he other 7 genes remain as obvious pseudogenes. This unexpected findin g raises the possibility that ail ndh genes have been transferred to t he nucleus or that an NADH dehydrogenase is not essential in black pin e chloroplasts.