钙缺乏对南瓜下胚轴细胞的影响：（31）P 核磁共振研究。

The effects of calcium deficiency on Cucurbita pepo L. hypocotyl cells: A (31)P nuclear-magnetic-resonance study.

机构信息

Department of Biochemistry, University of Cambridge, Tennis Court Road, CB2 1QW, Cambridge, UK.

出版信息

Planta. 1993 Mar;189(3):306-11. doi: 10.1007/BF00194426.

DOI:10.1007/BF00194426

Abstract

Calcium deficiency in zucchini (Cucurbita pepo L.) is associated with reduced growth and a reduced ability to transport auxin (Allan and Rubery, 1991, Planta 183, 604-612). An investigation of the effects of calcium-deficiency on zucchini hypocotyl cells was made using weak-acid uptake and (31)P-nuclear-magneticresonance ((31)P-NMR) spectroscopy in vivo and in tissue extracts. Calcium-deficient tissue had the same cytoplasmic and vacuolar pHs as normal tissue when extracellular pH was near neutral. At acidic external pH the vacuolar pH was lower in deficient tissue. Adenine nucleotides were present predominantly as ATP in both control and calcium-deficient tissues. Addition of calcium to calcium-deficient tissue, under conditions which cause recovery of auxin transport induced no changes in the (31)P-NMR spectra of deficient tissue. The content of mobile, phosphorylated metabolites was reduced in calcium-deficient tissue in comparison to control tissue. However, a substantial increase in the content of phosphorylcholine occurs in calcium-deficient tissues compared with controls; this may reflect changes in lipid turnover in calcium-stressed cells.

摘要

西葫芦（Cucurbita pepo L.）缺钙会导致生长减缓，并降低生长素（Auxin）的运输能力（Allan 和 Rubery，1991，Planta 183，604-612）。本研究采用弱酸摄取和（31）P 核磁共振波谱（（31）P-NMR）技术，在活体和组织提取物中，对缺钙对西葫芦下胚轴细胞的影响进行了研究。当细胞外 pH 值接近中性时，缺钙组织的细胞质和液泡 pH 值与正常组织相同。在酸性外部 pH 值下，缺钙组织的液泡 pH 值较低。在对照和缺钙组织中，腺嘌呤核苷酸主要以 ATP 的形式存在。在诱导生长素运输恢复的条件下，向缺钙组织中添加钙，不会导致缺钙组织的（31）P-NMR 谱发生变化。与对照组织相比，缺钙组织中可移动的磷酸化代谢物含量降低；然而，与对照组织相比，缺钙组织中磷酸胆碱的含量显著增加；这可能反映了钙胁迫细胞中脂类周转率的变化。