Abstract:

【Objective】 The objective of the study is to obtain full-length genes related to seed development and to provide resources for soybean genomics. 【Method】 A normalized cDNA library enriched in full-length sequences was constructed using DSN (duplex-specific nulease)-normalization method combined with SMARTTM(switching mechanism at 5’ end of RNA transcript) technique. 【Result】The titer of unamplified cDNA library was about 6.0×105 cfu/mL. The average cDNA inserts was more than 1.0 kb with a recombination rate of nearly 100%. After large-scale plasmid extraction and sequencing, 36 656 EST sequences were generated from the soybean seed cDNA library and the average length was more than 600 bp. All the EST sequences were assembled and 27 982 unigenes were gotten, which indicated that the cDNA library was a non-redundant library. 【Conclusion】 These results indicate that the normalized full-length cDNA library has been established successfully, which is convenient for further studying the molecular mechanism and gene cloning of seed development.

Key words: soybean, cDNA library, normalization, EST