1998 Fiscal Year Final Research Report Summary
Early evolution of land plants
| Project/Area Number |
08404055
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
系統・分類
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
KATO Masahiro The University of Tokyo, Graduate School of Science, Professor, 大学院・理学系研究科, 教授 (20093221)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
HASEBE Mitsuyasu National Institute of Basic Biology, Associate Professor, 基礎生物学研究所, 助教授 (40237996)
|
|---|
| Project Period (FY) |
1996 – 1998
|
| Keywords | land plant / early evolution / bryophyte / chloroplast DNA / molecular phylogeny / Psilotum nudum / MADS / homeotic genes |
|---|
| Research Abstract |
Our studies on (he early evolution of land plants had the following results :
1. A phylogenetic tree among three bryophyte classes and vascular plants was deduced based on partial nucleotide sequences of rbeL, psaA, psaB, psbD, and rpoC2 (456.3 bp in total). It was suggested that the hornworts are basal in land plant diversification and the mosses and liverworts are a monophyletic group which form sister groups with vascular Plants.
2. The nucleotide sequences were letermined of eDNA of MADS, HD-ZIP AND KNOX gene families isolated from Ceratopteris richardii (fern) and Physcomitrella pa tens (moss). The gene families are understood to play significant. roles in organ formation in flowering plants. A molecular phylogenetic tree suggested that. gene duplication took place prior to diversification of the land plant. groups. Analyses of gene expression showed that the genes may be organ-specific or generation-specific or not. show such specificity.
3. A library of tagged transforms was formed to establish an experimental system for isolating genes from transforms in Physcomitrella pa tens.
4. Cell lineages of apices were analyzed to determine the homology of the subterranean rhizome of the extant. primitive vascular plant. Psilotum nudum. The apical cell of the subterranean rhizome produces daughter apical cells in an irregular manner, resulting in the irregular branching pattern. Such irregularities are unique to the Psilotum nudum subterranean rhizome.
|
