玻璃化超低温保存中拟南芥幼苗细胞膜ATPase的变化

运用氯化铈(CeCl3)沉淀的电镜细胞化学方法, 研究了玻璃化超低温保存中拟南芥(Arabidopsis thaliana)不同苗龄幼苗细胞ATPase活性变化及玻璃化保护处理对酶活性的影响. 种子萌发48 h形成的幼苗(2 d龄幼苗)细胞膜ATPase活性反应强于种子萌发72 h形成的幼苗(3 d龄幼苗),但直接投入液氮(LN2)冻融后,2 d及3 d龄幼苗的ATPase全部失活. 玻璃化技术保护处理后, 2 d及3 d龄幼苗ATPase活性有不同程度提高. 2 d龄幼苗经玻璃化处理后ATPase活性明显提高,细胞膜ATPase在随之的LN2冻融后仍保持了较高活性;3 d龄幼苗经玻璃化处理后ATPase活性稍有提高,但LN2冻融后酶活性丧失. 幼苗玻璃化超低温保存结果显示,2 d及3 d龄幼苗直接投入LN2幼苗全部死亡. 玻璃化处理后再投入LN2,2 d龄幼苗有76%的成活率,而3 d龄幼苗仍然全部死亡. 结果表明,幼苗细胞膜ATPase活性与幼苗耐受LN2冻融后的成活率相关联. 玻璃化处理可以提高幼苗细胞膜ATPase活性,对2 d龄幼苗抗LN2冻融伤害有保护作用.

Changes of ATPase in plasma membrane during cryopreservation by vitrification with seedlings of Arabidopsis thaliana

ATPase activities of plasma membrane in 2 days old and 3 days old seedlings of Arabidopsis thaliana and the effects of cryopreservation by vitrification on them were studied with electromicroscopic cytochemical assay in which cerium trichloride precipitation method was adopted.The ATPase activities in plasma membrane of 2 days old seedlings were higher than those of 3 days old. But LN 2 freeze thaw induced the complete enzyme inactivation of those two kinds of seedlings and no seedling survival LN 2. Vitrification increased the enzyme activities of both 2 days and 3 days old seedlings in varying degrees. The ATPase activities of 2 days old seedlings obviously increased after vitrification and still showed high enzyme activities after LN 2 freeze thaw with 76% seedlings survival. Although the enzyme activities of 3 days seedlings increased slightly after vitrification, the enzyme complete inactivation after LN 2 freeze thaw and no seedling survived. The above results indicate that the vitrification enhanced the ATPase activities in plasma membrane of Arabidopsis seedlings and it was helpful for 2 days old seedlings resistant LN 2 freeze thaw stress. The ATPase activities of seedlings had relation to resistant liquid nitrogen ( LN 2 ) freeze thaw.