NaCl-Induced Alterations in Both Cell Structure and Tissue-Specific Plasma Membrane H+ -ATPase Gene Expression
X. Niu1, B. Damsz, A. K. Kononowicz
1Center for Plant Environmental Stress Physiology, Purdue University, 1165 Horticulture Building, West Lafayette, Indiana 47907-1165.
Plant Physiology
|July 1, 1996
Summary
This study reveals specific root and leaf tissues in the halophyte Atriplex nummularia that regulate sodium and chloride uptake. These findings highlight intercellular and interorgan coordination for NaCl adaptation in plants.
Area of Science:
- Plant Physiology
- Molecular Biology
- Biochemistry
Background:
- Halophytes like Atriplex nummularia L. possess mechanisms to adapt to high salinity.
- Plasma membrane H+-ATPase plays a crucial role in ion transport and cellular homeostasis under salt stress.
Purpose of the Study:
- To investigate the tissue-specific localization of NaCl-induced plasma membrane H+-ATPase gene expression in Atriplex nummularia.
- To understand the cellular adaptations associated with salt tolerance in this halophyte.
Main Methods:
- In situ RNA hybridization to localize gene expression.
- Ultrastructural analysis of root cell cytological adaptations.
Main Results:
- NaCl exposure led to H+-ATPase gene expression accumulation in root epidermis and endodermis.
- In leaves, expression was localized to bundle-sheath cells.
- Root cells showed plasmolysis, plasma membrane invaginations, Hechtian strands, vesiculation, and vacuolation.
Conclusions:
- Specific tissues in roots and leaves are identified as key players in regulating Na+ and Cl- uptake.
- Evidence suggests intercellular and interorgan coordination in mediating NaCl adaptation in A. nummularia.
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