title: Adaptive evolution of rbcL in Conocephalum (Hepaticae, bryophytes).
abstract: An excess of nonsynonymous substitutions over synonymous ones has been regarded as an important indicator of adaptive evolution or positive selection at the molecular level. We now report such a case for rbcL sequences among cryptic species in Conocephalum (Hepaticae, Bryophytes). This finding can be regarded as evidence of adaptive evolution in several cryptic species (especially in F and JN types) within the genus. Bryophytes are small land plants with simple morphology. We can therefore expect the existence of several biologically distinct units or cryptic species within each morphological species. In our previous study, we found three rbcL types in Asian Conocephalum japonicum (Thunb.) Grolle and also found evidence strongly suggesting that the three types are reproductively isolated cryptic species. Additionally, we examined rbcL sequence variation in six cryptic species of C. conicum (L.) Dumort. previously recognized by allozyme analyses. As a result, we were able to discriminate the six cryptic species based only on their rbcL sequences. We were able to show that rbcL sequence variation is also useful in finding cryptic species of C. conicum.
authors.affiliation: Genome and Drug Research Center, Tokyo University of Science, Chiba, Japan.
authors.forename: Hidetsugu
authors.initials: H
authors.lastname: Miwa
authors.forename: Ireneusz J
authors.initials: IJ
authors.lastname: Odrzykoski
authors.forename: Atsushi
authors.initials: A
authors.lastname: Matsui
authors.forename: Masami
authors.initials: M
authors.lastname: Hasegawa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Akiyama
authors.forename: Yu
authors.initials: Y
authors.lastname: Jia
authors.forename: Renat
authors.initials: R
authors.lastname: Sabirov
authors.forename: Hideki
authors.initials: H
authors.lastname: Takahashi
authors.forename: David E
authors.initials: DE
authors.lastname: Boufford
authors.forename: Noriaki
authors.initials: N
authors.lastname: Murakami
mesh_terms: D019943:Amino Acid Substitution; D001483:Base Sequence; D005075:Biological Evolution; D044002:Bryophyta / Q000235:genetics*; D019143:Evolution, Molecular; D007527:Isoenzymes / Q000235:genetics; D010802:Phylogeny; D012273:Ribulose-Bisphosphate Carboxylase / Q000235:genetics
chemical_list: D007527:Isoenzymes; C101625:RbcL protein, plastid; D012273:Ribulose-Bisphosphate Carboxylase