CHOLINE SYNTHESIS IN SPINACH IN RELATION TO SALT STRESS

被引:58
作者
SUMMERS, PS [1 ]
WERETILNYK, EA [1 ]
机构
[1] MCMASTER UNIV,DEPT BIOL,HAMILTON L8S 4K1,ONTARIO,CANADA
关键词
D O I
10.1104/pp.103.4.1269
中图分类号
Q94 [植物学];
学科分类号
071001 ;
摘要
Choline metabolism was examined in spinach (Spinacia oleracea L.) plants growing under nonsaline and saline conditions. In spinach, choline is required for phosphatidylcholine synthesis and as a precursor for the compatible osmolyte glycine betaine (betaine). When control (nonsalinized) leaf discs were incubated for up to 2 h with [1,2-C-14]ethanolamine, label appeared in the N-methylated derivatives of phosphoethanolamine including phosphomono-, phosphodi-, and phosphotri- (i.e. phosphocholine) methyl-ethanolamine, as well as in choline and betaine, whereas no radioactivity could be detected in the mono- and dimethylated derivatives of the free base ethanolamine. Leaf discs from salinized plants showed the same pattern of labeling, although the proportion of label that accumulated in betaine was almost 3-fold higher in the salinized leaf discs. Enzymes involved in choline metabolism were assayed in crude leaf extracts of plants. The activities of ethanolamine kinase and of the three S-adenosylmethionine:phospho-base N-methyltransferase enzymes responsible for N-methylating phosphoethanolamine to phosphocholine were all higher in extracts of plants salinized step-wise to 100, 200, or 300 mm NaCl compared with controls. In contrast, choline kinase, phosphocholine phosphatase, and cytidine 5'-triphosphate:phosphocholine cytidylyltransferase activities showed little variation with salt stress. Thus, the increased diversion of choline to betaine in salt-stressed spinach appears to be mediated by the increased activity of several key enzymes involved in choline biosynthesis.
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页码:1269 / 1276
页数:8
相关论文
共 24 条
[1]  
BRADFORD MM, 1976, ANAL BIOCHEM, V72, P248, DOI 10.1016/0003-2697(76)90527-3
[2]   EVIDENCE FOR A FERREDOXIN-DEPENDENT CHOLINE MONOOXYGENASE FROM SPINACH CHLOROPLAST STROMA [J].
BROUQUISSE, R ;
WEIGEL, P ;
RHODES, D ;
YOCUM, CF ;
HANSON, AD .
PLANT PHYSIOLOGY, 1989, 90 (01) :322-329
[3]   GLYCINEBETAINE BIOSYNTHESIS AND ITS CONTROL IN DETACHED SECONDARY LEAVES OF SPINACH [J].
COUGHLAN, SJ ;
JONES, RGW .
PLANTA, 1982, 154 (01) :6-17
[4]   PHOSPHATIDYLCHOLINE SYNTHESIS - DIFFERING PATTERNS IN SOYBEAN AND CARROT [J].
DATKO, AH ;
MUDD, SH .
PLANT PHYSIOLOGY, 1988, 88 (03) :854-861
[5]   ENZYMES OF PHOSPHATIDYLCHOLINE SYNTHESIS IN LEMNA, SOYBEAN, AND CARROT [J].
DATKO, AH ;
MUDD, SH .
PLANT PHYSIOLOGY, 1988, 88 (04) :1338-1348
[6]   NEW METHOD FOR ASSAY OF TISSUE S-ADENOSYLHOMOCYSTEINE AND S-ADENOSYLMETHIONINE - EFFECT OF PYRIDOXINE-DEFICIENCY ON METABOLISM OF S-ADENOSYLHOMOCYSTEINE, S-ADENOSYLMETHIONINE AND POLYAMINES IN RAT-LIVER [J].
ELORANTA, TO ;
KAJANDER, EO ;
RAINA, AM .
BIOCHEMICAL JOURNAL, 1976, 160 (02) :287-294
[7]   COMPARATIVE PHYSIOLOGICAL EVIDENCE THAT BETA-ALANINE BETAINE AND CHOLINE-O-SULFATE ACT AS COMPATIBLE OSMOLYTES IN HALOPHYTIC LIMONIUM SPECIES [J].
HANSON, AD ;
RATHINASABAPATHI, B ;
CHAMBERLIN, B ;
GAGE, DA .
PLANT PHYSIOLOGY, 1991, 97 (03) :1199-1205
[8]   BETAINE ACCUMULATION AND [FORMATE-C-14 METABOLISM IN WATER-STRESSED BARLEY LEAVES [J].
HANSON, AD ;
NELSEN, CE .
PLANT PHYSIOLOGY, 1978, 62 (02) :305-312
[9]   C-14 TRACER EVIDENCE FOR SYNTHESIS OF CHOLINE AND BETAINE VIA PHOSPHORYL BASE INTERMEDIATES IN SALINIZED SUGARBEET LEAVES [J].
HANSON, AD ;
RHODES, D .
PLANT PHYSIOLOGY, 1983, 71 (03) :692-700
[10]   RADIOTRACER EVIDENCE IMPLICATING PHOSPHORYL AND PHOSPHATIDYL BASES AS INTERMEDIATES IN BETAINE SYNTHESIS BY WATER-STRESSED BARLEY LEAVES [J].
HITZ, WD ;
RHODES, D ;
HANSON, AD .
PLANT PHYSIOLOGY, 1981, 68 (04) :814-822