| Solaneace plays a great role in both of agriculture and the study of biology science. In agronomy, it is the third most important plant taxa over the world's crops. Lots of Solaneace plants are widely cropped over the earth for staple food, vegetables, medicines, industry materials and so on. From the aspect of science research, Solaneace is essential to investigate the secret of adaptation and diversity for this family has widely habitats and high level phenotypic variation but all the members share very similar genomes and gene repertoire. In order to get insights of the genetics of this important family and develop related study, the model Solaneace tomato and the most economically important member potato are put into genome sequencing by two international projects separately. International Solanaceae Genome Project (SOL) is designated to obtain the sequence of complete 220 Mb euchromatin portion of tomato genome, expecting that portion containing the majority of genes, while the Potato Genome Sequencing Consortium (PGSC) aims at generating a draft sequence of the 840 Mb of potato genome.The map-based BAC-by-BAC strategy and sanger sequence technology are used in both of the two projects in order to get precisely sequence。It asks to construct developed BAC libraries covering the whole genomes and create FPC (Finger-printed-contigs) physical map. Then integrate the ultra high density genetic map and the physical map. From the integrating information, select the right BACs (seed BACs) for sequencing and then extend out from the both directions of these clones using the BAC ends sequences, physical map and Fish analysis until cover the goal interval.China participates both of the tomato and potato genome projects taking responsibility of Chromosome III, XI of tomato and Chromosome X, XI of potato. Chinese academy of agriculture science is in charge of sequencing all the chromosomes except tomato chromosome 3. Both projects have been initiated in China and set up a system of BAC selecting, verifying, sequencing, quality control, sequence assemlby, data integration, and bioinformatics analysis. Based on the discovery of highly degree of similarity of tomato and potato genomes, comparative genomics plays an important role when we sequence the chromosome XI of tomato and potato at the same time. This method has been proved to be useful in seed BAC selecting, improving physical map, and sequence asseMLBy. Analysis of the paired tomato and potato BACs in chromosome 11 using bioinformatics tools reveals homology level and different features between these two genomes in chromosome 11. Besides, a resistance gene cluster was found in the long arm of chromosome 11. This locus is every rich of R-gene analogs and homologous to the R3a locus in SH. Sequencing the BACs from this locus and comparing with the homologous sequence from SH revealed the features of the R-gene rich locus. Further investigation of these loci may give new insights to understand the evolution basis of R-gene clusters.These genome sequencing projects of two Solaneace plants will present a great bench for study of this family both in biology science and genetics and breeding. Participating these two genome projects not only gives China the opportunity to develop the Solanaceae research but improves China as a great country in genome research.
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