response to high-salt stress in Halophyte cells

盐生植物能够在高盐环境下生长。为了研究盐生植物细胞对盐胁迫的反应，用0.2M NaCl处理和不处理来自3种滨藜属（Atriplex）的培养细胞：1 entiformis（AL）、halimus（AH）和halimus（AH），并通过二维电泳分析多肽模式。在NEPHGE/SDS电泳上，盐处理的滨藜细胞不溶性蛋白质组分中的多肽斑点显著增加。一种名为SP1的多肽分子量为27 kDa，pI大于8.5。该多肽为具有ConA结合活性的糖蛋白。从LH电泳点洗脱的蛋白用于小鼠制备抗体和N-末端氨基酸测序。从盐处理的LH细胞中提取mRNA，制备cDNA文库，并使用由N端氨基酸序列构建的引物通过PCR扩增的探针进行文库筛选。我们已经测定了SP1的全长cDNA的核苷酸序列，并提交到DDBJ/EMBL/GenBank数据库（AB 024338）。还原的氨基酸序列显示SP1为224-AA，24 kDa，pI=9.72。检索GenBank数据库的SP1氨基酸序列显示与Germin和琥珀酸氧化酶相似。

Halophyte plants are able to grow under high saline environments. For examining cellular response of Halophyte cells to salt stress, cultured cells from 3 Atriplex species ; 1 entiformis (AL), halimus (AH) and halimus (AH) were treated with and without 0.2M NaCl, and polypeptide patterns were analyzed by 2-D electrophoresis. Significant increase of polypeptide spot were detected in insoluble protein fractions of salt treated Atriplex cells on NEPHGE/SDS electrophoresis. A polypeptide named SP1 was with a molecular mass of 27 kDa with pI over 8.5. The polypeptide was glycoprotein with Con A binding activity. Eluted proteins from electrophoretic spot of LH were used for antibody preparation by mice and N-terminal amino acid sequencing. mRNA were isolated from salt-treated LH cells and cDNA library was prepared, and library screening were done using a probe, which amplified by PCR on primers constructed from N-terminal amino-acid sequences. We have determined the nucleotide sequence of a full length cDNA for SP1 and submitted on the DDBJ/EMBL/GenBank databases (AB024338). Reduced amino acid sequences reveals that SP1 is 224-AA, 24 kDa and pI=9.72. A search of the GenBank data base for SP1 amino acid sequence showed similarity to Germin and oxalate-oxidase.