Cloning of genes conferring allergenic proteins and salt tolerance by screening a full length cDNA library in soybean.

摘要

To obtain genes conferring allergenic proteins and salt tolerance of vegetable soybean (Glycine max (L.) Merr.), a full-length cDNA library from the developing seeds of 'NN99-10' was constructed and characterized. Gel-electrophoresis results showed that most of the cDNA inserts ranged from 0.40 to 2.0 kb, with an average size c. 800 bp. Randomly-picked clones showed that the recombination rate was >99%. This indicated that the cDNA library constructed was a full-length library with high quality. After blue/white selection followed by sequencing of the positive cDNA clones from the constructed library, a total of 642 expressed sequence tags (ESTs) were identified, 468 of which contained full-length coding regions. Based on bioinformatic analysis of the sequences, a total of 395 full-length cDNA clones were homologous to various known genes in soybean and other species. The remaining 73 full-length cDNA clones showed little homology to known sequences, which might be considered novel. The identified 395 full-length cDNA clones fell into 8 functional categories, including modifications and precursors of protein (26.31%), protein synthesis (22.24%), and defense proteins (22.20%). A total of eleven genes of agronomic importance were identified, among which eight related to seed quality (four genes conferring allergenic proteins) and three conferring salt tolerance.