Phan Huyen T T, Ellwood Simon R, Ford Rebecca, Thomas Steve, Oliver Richard
Australian Centre of Necrotrophic Plant Pathogens, State Agricultural Biotechnology Centre, Murdoch University, South Street, Murdoch, WA 6150, Australia.
BioMarka, Faculty of Land and Food Resources, The University of Melbourne, Parkville, Vic. 3010, Australia.
Funct Plant Biol. 2006 Aug;33(8):775-782. doi: 10.1071/FP06102.
Orthologous markers transferable between distantly related legume species allow for the rapid generation of genetic maps in species where there is little pre-existing genomic or EST information. We are using the model legume Medicago truncatula Gaertn. to develop such markers in legumes of importance to Australian agriculture. This will enable the construction of comparative genetic maps, help to determine patterns of chromosomal evolution in the legume family, and characterise syntenic relationships between M. truncatula and cultivated legumes. This information can then be used to identify markers that are tightly linked to the genes of interest, candidate gene(s) for a trait, and expedite the isolation of such genes. Among the Papilionoideae, we compared ESTs from the phylogenetically distant species, M. truncatula, Lupinus albus and Glycine max, to produce 500 intron-targeted amplified polymorphic markers (ITAPs). In addition to 126 M. truncatula cross-species markers from Department of Plant Pathology, University of California (USA), these markers were used to generate comparative genetic maps of lentil (Lens culinaris Medik.) and white lupin (Lupinus albus Linn.). Our results showed that 90% of the ITAPs markers amplified genomic DNA in M. truncatula, 80% in Lupinus albus, and 70% in Lens culinaris. The comparative map of Lens culinaris was constructed based on 79 ITAP markers. The Lupinus albus comparative map was developed from 105 gene-based markers together with 223 AFLP markers. Although a direct and simple syntenic relationship was observed between M. truncatula and Lens culinaris genomes, there is evidence of moderate chromosomal rearrangement. This may account for the different chromosome numbers in the two species. A more complicated pattern among homologous blocks was apparent between the Lupinus albus and M. truncatula genomes.
可在亲缘关系较远的豆科植物物种之间转移的直系同源标记，能够在几乎没有预先存在的基因组或EST信息的物种中快速构建遗传图谱。我们正在利用豆科模式植物蒺藜苜蓿（Medicago truncatula Gaertn.）来开发对澳大利亚农业具有重要意义的豆科植物中的此类标记。这将有助于构建比较遗传图谱，有助于确定豆科家族的染色体进化模式，并表征蒺藜苜蓿与栽培豆科植物之间的同线关系。然后，这些信息可用于识别与感兴趣基因紧密连锁的标记、性状的候选基因，并加速此类基因的分离。在蝶形花亚科中，我们比较了系统发育关系较远的物种蒺藜苜蓿、白羽扇豆（Lupinus albus）和大豆（Glycine max）的EST，以产生500个内含子靶向扩增多态性标记（ITAP）。除了来自美国加利福尼亚大学植物病理学系的126个蒺藜苜蓿跨物种标记外，这些标记还用于构建小扁豆（Lens culinaris Medik.）和白羽扇豆（Lupinus albus Linn.）的比较遗传图谱。我们的结果表明，90%的ITAP标记能在蒺藜苜蓿中扩增基因组DNA，80%能在白羽扇豆中扩增，70%能在小扁豆中扩增。基于79个ITAP标记构建了小扁豆的比较图谱。白羽扇豆的比较图谱由105个基于基因的标记和223个AFLP标记构建而成。虽然在蒺藜苜蓿和小扁豆基因组之间观察到直接而简单的同线关系，但有证据表明存在中度的染色体重排。这可能解释了这两个物种染色体数目的差异。在白羽扇豆和蒺藜苜蓿基因组之间，同源区段之间的模式更为复杂。
