Isolation And Screening Of Gene Fragments Related To Salt Stress In Wheat

The soil salification is a serious problem for aghcultUre and envirOnment. Theshrinkage in arable land and the lack of freshwaer resource has forced mankind toexPlore the USage of large areas of saline soil, sea shores and beaches. Therefore,scientistS in the world have devoted much attention to stUdy the biochendcal andmolecular biological mechbosms of salt-tolerance in high plans Which has been due toitS irnportance in the theory StUdy and prachcal aPplication. It is a key problem in therecent stUdies of plan molecular biology ResultS from Saccharomyces cerevisiae andthe model orgbosms such as Arabmpis thahana and rice are paving the way forMing the molecular basis of salt tOlerane. Howevet the molecLilarmechbosm of salt tolerane in wheat remains largely Imknown. To addrss this, aW finger prining technique c DNA-AFLP (c DNA- amp l ifi e d fragInellt lengthPOlyInophism) is used to anaisis gene expression difference in saltthessed andwtssed Wheat 98-l60, Which is a salt-stress resistan line. Seventy four pairs ofselective priInrs with used for aInPlification, 26 differential disPlay of cDNAfragInents, including l2 salt-forssed induced exPression fragmnts, 4 salt-sbessedintensive exPression fragInents and l0 salt-Stressed dribition exPression fragments,have been isolated from salt-StrCss Whe8t leaves by cDNA-AFLR Thre fragInentShave been screened by Reverse NOrthern Blot. IhaItheImere,chBfoforthat2 wtS I' SII)are identified. The result reveals that expression of S I, S II isStrongly induced in Wheat.leaftissue by salt-Stress. In thes studX S I' S II have beencloned and sequenced for ther StUdy the StructUre of them. The result indicates thatS I is comPosed of 307bP and S II is comPosed of 200bp. cDNA sequence analysisshows 50W70% homologUe to a system of ldnases in GenBank. May bc S I is a genefragInent related to salttolerance. S II shows no datectable homology to known genes,suggesting that it probably rePresents fragInent of a novel gene.