植物学报
植物學報
식물학보
ACTA BOTANICA SINICA
2003年
1期
93-97
,共5页
马长乐%王萍萍%曹子谊%赵彦修%张慧
馬長樂%王萍萍%曹子誼%趙彥脩%張慧
마장악%왕평평%조자의%조언수%장혜
过氧化氢酶%盐胁迫%盐地碱蓬%活性氧
過氧化氫酶%鹽脅迫%鹽地堿蓬%活性氧
과양화경매%염협박%염지감봉%활성양
catalase%salt stress%Suaeda salsa%reactive oxygen species
过氧化氢酶是清除H2O2的重要酶类.从400 mmol/L NaCl处理的盐地碱蓬(Suaeda salsa(L.)Pall)地上部分的cDNA文库中克隆了两个编码过氧化氢酶的cDNA(Sscat1和Sscat2),其中Sscat1(1.7kb)是一个全长cDNA克隆,编码一个492个氨基酸的开放阅读框架,而Sscat2(1.1kb)是一个cDNA片段.据编码Sscat1 3＇端的287个氨基酸的cDNA序列与Sscat2的cDNA序列进行的BLAST同源性分析表明,Sscat1和Sscat2在核苷酸水平的一致性为71.9%,在氨基酸水平上的一致性为75%.Southem杂交表明,Sscat1在盐地碱蓬基因组中为多拷贝基因,Sscat2则为一个单拷贝基因.Northern杂交结果表明在盐胁迫条件下Sscat1和Sscat2的表达存在差异:400 mmol/L NaCl处理48h的盐地碱蓬根中的Sscat1和Sscat2 mRNA水平比对照显著提高,但是在叶中仅Sscatl受盐诱导表达.不同盐处理时间下的表达分析也证实,在盐地碱蓬叶中仅Sscat1受盐诱导表达.这说明Sscat1和Sscat2在盐地碱蓬中是差异调控的.生理分析表明过氧化氢酶的活性在盐胁迫条件下显著提高.
過氧化氫酶是清除H2O2的重要酶類.從400 mmol/L NaCl處理的鹽地堿蓬(Suaeda salsa(L.)Pall)地上部分的cDNA文庫中剋隆瞭兩箇編碼過氧化氫酶的cDNA(Sscat1和Sscat2),其中Sscat1(1.7kb)是一箇全長cDNA剋隆,編碼一箇492箇氨基痠的開放閱讀框架,而Sscat2(1.1kb)是一箇cDNA片段.據編碼Sscat1 3＇耑的287箇氨基痠的cDNA序列與Sscat2的cDNA序列進行的BLAST同源性分析錶明,Sscat1和Sscat2在覈苷痠水平的一緻性為71.9%,在氨基痠水平上的一緻性為75%.Southem雜交錶明,Sscat1在鹽地堿蓬基因組中為多拷貝基因,Sscat2則為一箇單拷貝基因.Northern雜交結果錶明在鹽脅迫條件下Sscat1和Sscat2的錶達存在差異:400 mmol/L NaCl處理48h的鹽地堿蓬根中的Sscat1和Sscat2 mRNA水平比對照顯著提高,但是在葉中僅Sscatl受鹽誘導錶達.不同鹽處理時間下的錶達分析也證實,在鹽地堿蓬葉中僅Sscat1受鹽誘導錶達.這說明Sscat1和Sscat2在鹽地堿蓬中是差異調控的.生理分析錶明過氧化氫酶的活性在鹽脅迫條件下顯著提高.
과양화경매시청제H2O2적중요매류.종400 mmol/L NaCl처리적염지감봉(Suaeda salsa(L.)Pall)지상부분적cDNA문고중극륭료량개편마과양화경매적cDNA(Sscat1화Sscat2),기중Sscat1(1.7kb)시일개전장cDNA극륭,편마일개492개안기산적개방열독광가,이Sscat2(1.1kb)시일개cDNA편단.거편마Sscat1 3＇단적287개안기산적cDNA서렬여Sscat2적cDNA서렬진행적BLAST동원성분석표명,Sscat1화Sscat2재핵감산수평적일치성위71.9%,재안기산수평상적일치성위75%.Southem잡교표명,Sscat1재염지감봉기인조중위다고패기인,Sscat2칙위일개단고패기인.Northern잡교결과표명재염협박조건하Sscat1화Sscat2적표체존재차이:400 mmol/L NaCl처리48h적염지감봉근중적Sscat1화Sscat2 mRNA수평비대조현저제고,단시재협중부Sscatl수염유도표체.불동염처리시간하적표체분석야증실,재염지감봉협중부Sscat1수염유도표체.저설명Sscat1화Sscat2재염지감봉중시차이조공적.생리분석표명과양화경매적활성재염협박조건하현저제고.
Two different cDNA clones (Sscatl and Sscat2) encoding catalase, the primary important H2O2-scavenging enzyme, were isolated from a λZap-cDNA library constructed from a 400 mmol/L NaCl-treated library of Suaeda salsa ( L. ) Pall aerial tissue. Sscatl ( 1.7 kb) contains a full open reading frame of 492amino acids and Sscat2 (1.1 kb) is a partial clone. BLAST analysis indicates that the two clones share 71.9 % identity in nucleotide sequence and 75 % identity in deduced amino acid sequence within the last 287amino acid residues of Sscatl. Southern blotting analysis showed that Sscatl is multicopy in S. salsa genome, while Sscat2 is a single copy gene. Northern blotting analysis showed a rapid increase in the steadylevel of both genes in roots after 48 h salt treatment, but only Sscatl was induced in salinity treated leaves.Time-course analysis carried out in leaves confirmed that Sscatl was induced by salt stress, in contrast to Sscat2. These implied that the expression of Sscatl and Sscat2 genes are differentially regulated in S. salsa.The activity of total catalase is dramatically increased in response to salt stress.
