Conservation of Arabidopsis flowering genes in model legumes.
The model plants Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) have provided a wealth of information about genes and genetic pathways controlling the flowering process, but little is known about the corresponding pathways in legumes. The garden pea (Pisum sativum) has been used for several decades as a model system for physiological genetics of flowering, but the lack of molecular information about pea flowering genes has prevented direct comparison with other systems. To address this problem, we have searched expressed sequence tag and genome sequence databases to identify flowering-gene-related sequences from Medicago truncatula, soybean (Glycine max), and Lotus japonicus, and isolated corresponding sequences from pea by degenerate-primer polymerase chain reaction and library screening. We found that the majority of Arabidopsis flowering genes are represented in pea and in legume sequence databases, although several gene families, including the MADS-box, CONSTANS, and FLOWERING LOCUS T/TERMINAL FLOWER1 families, appear to have undergone differential expansion, and several important Arabidopsis genes, including FRIGIDA and members of the FLOWERING LOCUS C clade, are conspicuously absent. In several cases, pea and Medicago orthologs are shown to map to conserved map positions, emphasizing the closely syntenic relationship between these two species. These results demonstrate the potential benefit of parallel model systems for an understanding of flowering phenology in crop and model legume species.
Hecht
Valérie
V
School of Plant Science, University of Tasmania, Hobart, Tasmania 7001, Australia.
Foucher
Fabrice
F
Ferrándiz
Cristina
C
Macknight
Richard
R
Navarro
Cristina
C
Morin
Julie
J
Vardy
Megan E
ME
Ellis
Noel
N
Beltrán
José Pío
JP
Rameau
Catherine
C
Weller
James L
JL
D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development*; D001483:Base Sequence; D002874:Chromosome Mapping; D002940:Circadian Rhythm / Q000235:genetics; D017124:Conserved Sequence; D018744:DNA, Plant / Q000235:genetics; D007887:Fabaceae / Q000235:genetics* / Q000254:growth & development*; D035264:Flowers / Q000254:growth & development; D017343:Genes, Plant; D008957:Models, Genetic; D008969:Molecular Sequence Data; D005810:Multigene Family; D009154:Mutation; D018532:Pisum sativum / Q000235:genetics / Q000254:growth & development; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics
D018744:DNA, Plant; D045322:Photosynthetic Reaction Center Complex Proteins; D010940:Plant Proteins