Tanaka K, Takio S, Yamamoto I, Satoh T
Department of Biological Science, Faculty of Science, Hiroshima University, Japan.
Plant Cell Physiol. 1998 Feb;39(2):235-40. doi: 10.1093/oxfordjournals.pcp.a029362.
Suspension-cultured cells of the liverwort Marchantia paleacea var. diptera contain a cytosolic CuZn-superoxide dismutase (SOD) whose N-terminal amino acid sequence is similar to those of the isozymes found in chloroplasts of higher plants [Tanaka et al. (1996) Plant Cell Physiol. 37: 523]. A cDNA (MSODCc) encoding the cytosolic CuZn-SOD was isolated from cDNA library constructed from a liverwort cell suspension culture. The deduced amino acid sequence showed a higher degree of homology with the sequences of CuZn-SODs in chloroplasts than those in the cytosol of higher plants and an unique additional peptide in the C-terminal region, but no plastid transit sequence. Northern blotting using MSODCc as a probe and immunoblot analysis with antiserum against the enzyme revealed that the steady state level of transcript was not affected by copper, but both CuZn-SOD protein and its activity increased.
苔类植物二歧紫背苔悬浮培养细胞含有一种胞质铜锌超氧化物歧化酶（SOD），其N端氨基酸序列与高等植物叶绿体中发现的同工酶相似[田中等人（1996年）《植物细胞生理学》37:523]。从苔类植物细胞悬浮培养构建的cDNA文库中分离出编码胞质铜锌超氧化物歧化酶的cDNA（MSODCc）。推导的氨基酸序列与叶绿体中铜锌超氧化物歧化酶的序列相比，与高等植物胞质中的序列具有更高的同源性，并且在C端区域有一个独特的额外肽段，但没有质体转运序列。以MSODCc为探针的Northern印迹分析和用该酶抗血清进行的免疫印迹分析表明，转录本的稳态水平不受铜的影响，但铜锌超氧化物歧化酶蛋白及其活性均增加。
