LEE, JUNGHO* and JAMES R. MANHART. Department of Biology, Texas A&M University, College Station, TX 77843-3258, U.S.A.,. - The transition from algae to embryophytes: Chloroplast phylogenomic evidence II
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The transition of plant life from aquatic algae to land plants was one
of the major events in the history of life. However, in hypothesizing
the evolutionary path of the transition, limited shared phenotypic
characters in aquatic algae and land plants (embryophytes) have been a
major hinderance. Chloroplast genomes contain characters useful in
tracing evolutionary histories. Embryophyte chloroplast genomes are
distinguished from algal cpDNAs by the presence of over 20 group II
introns and three ribosomal protein operons ( rpl23,
clpP and 3Śrps12 operons). These phylogenomic features
indicate a phylogenetic relationship of charophytes and embryophytes.
In addition to these operons and introns, the evolution of rRNA
and psbB operon evolution of streptophyte lineages will be
incorporated with major biological phenotypic features to produce a
phylogenetic tree. Basal embryophytes, the antithetic hypothesis,
monophyly of embryophytes, and paraphyly of charophytes will be
discussed. Strepotophytes are classified into three major groups,
(basal streptophytes, mid-divergent streptophytes and late divergent
charophytes-embryophytes).
Key words: 3'rps12 operon, basal streptophytes, charophytes, clpP operon, embryophytes, rpl23 operon
clpP operon, rpl23 operon