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Heat shook proteins localization in leaf cells of Arabidopsis
Cell Biology international
P165
LIPID BODY ACCUMULATION IN NITROGENFIXING ROOT NODULES OF PEANUT
Arya, K. Bal, Abubaker M. Siddique, Department of Biology, Memorial University of Newfoundland, St. John's, NF Canada AlB 3X9. Nitrogen-fixingpeanutnodules are characterized by the presence of lipid bodies (oleosomes) in the infected cells. (Bal et al Protoplasma 150, 1989). It has been suggested that they serve as a supplementary source of energy for the high energy demanding process of nitrogen fixation. In this investigation nodules induced by mutant strains of rhizobia, which are incapable of fixing nitrogen (fix-) have been studied with a view to understanding the functional significance of lipid bodies in the root nodules. Nodules at different stages of development were fixed for routine transmission electron microscopy. A special staining technique using p-phenylenediamine was employed to localize lipid bodies in plastic sections. Control preparations were made using lipid solvents to check for non-specific staining. measurements made using a Morphometric were digital analyser (Carl Zeiss MOP-3), and the number of lipid bodies and their % area in the cell were determined. In nodules induced by two fix- strains of rhizobia revealed 2-3 times snore lipid body accumulation than in the ones induced by the wild type, where nitrogen fixation occurs The accumulation of lipid bodies in vigorously. absence of nitrogen fixation indicates that they are utilized in the nitrogen reduction process. (Supported by Natural Sciences and Engineering Research Council of Canada).
EFFECTOF ENVIRONMENTAL STRESSES ON PLANT DELL ULTRASTRUCTURE Valentina Khokhlova, Svetlana Porfirova. Institute of Plant Physiology Aoad.of Soi. USSR, Botanicheskaya 35, Moscow, USSR We investigate the effect of heat (400), saline (0,5M NaCl), dehydration (0,5M mannitol) and wound stresses on cell ultrastructure end heat shock proteins (HSP) 70 and 17 kDa localization in tip root cells of Cucurbita pepo L. seedlings. These stresses induce unspecific and specific changes in cell ultrastructure. We were first to show that salinity, dehydration and wounding cause cytoplasmic stress granules (SO) formation as heat shock (HS) does. The morphology of SG depends on stress type, duration and severety. SG are transient structures which disappear during recovery period. Using immunogold techique we study cellular localization of HSP 70 and 17 kDa under various stresses (polyclonal antibodies to these HSP were courtesely presented US by dr. D.Neumann, Institute of Plant Biochemistry, GDR). SO formed under HS in pumpkin root cells are found to contain HSP 70 end 17 kDa,whereas SG formed under other stresses contain rather low quantities of these proteins. It is evidently that SG formed under ve,rious stresses have different protein composition but the phenomenon of their appeerenoe is universal plant response toward environmental stresses. Pm7
P166
Reports, Vol. 14, Abstracts Supplement
STARCH DETECTION
Canavalia
1990
AND DOSAGE IN DC.
Angelo Luiz Cortelazzo & Benedict0 Dept.Cell Biology - I.B. - UNICAMP 13081 - Campinas - SP - Brazil.
de Campos Vidal - C.P. 6109 -
reserves in To analyse the use of starch amyloplasts during the initial development of the plant species Canavalia ensiformis (L.)DC. and C. gladiata (Jacqmeasurements were made ?? variations in starch content of cotyledons at 0, 7, 14, 21 and 28 days after imbibing. The material was fixed, embedded in paraffin, sectioned ( 8 pm thick) and submitted to PAS reaction. The starch grains were counted for each cell and their area and volume calculated. Reserve material was also extracted and starch dosage measured for each of the development periods. The results for an area of approximately 400 pm'and a volume of 5,600 pm' showed that 4 grains per cell is the average number up to the 7th day of imbibing for G ensiformis and up to 14th day for C. gladiata. The quantity falls to almost zero after 21 or 28 days of respectively. Dosage measurements imbibing, revealed an initial content of 744 ma of starch oer seed ( 56% dry weight) in C. ensiformis and 2,394 mg per seed (53% dry weist.) in C. gladiata. This investiqation demonstrated the reEtion between number-of amyloplasts per cell and the the plants dosage (mg/g dry weight), and that consume about 98.5% of this reserve during development up to cotyledon abcision.
HEAT SHOONPROTEINS I&CALIZATION INLEAF CELLS OFIRILBIDOPSIS Svetlana Porfirova, Valentina Ehokhlova, Natalya Yu Nlyueva. Institute of Plant Physiology,Acad. of Sci. USSR, Botenicheskaya 35, Moecow, USSR The localization of heat shock proteins (HSP) in Arabidopsis thaliana leaf cells was studied with polyclonal antibodies raised again& HSP 70 and 17 kDa of tomato cell suspension culture using protein A-gold technique. High and low moleou3.ar weight HSP, immuuologiGally relative to tomato HSP 70 and 17 were looalized in nuclei and in cytoplasmic heat shook granules (HSG) under heat shock (37O). ml7 were mainly accumulated in HSG and HSP 70 in nuolei. The dynemios of HSG formation (37O) and their degradation in normal conditions (23OI was studied. Dependenoe of HSG formation on RNA end protein synthesis was oharacterized. Cordycepin (200 mkg/ml) inhibited the synthesis of HSP 17 and HSGformation, slightly reduce ted the synthesis of HSP 70 and didn't change its nuolesr looalization. Cycloheximide (IO mkg/ml) oompletly inhibited HSP 70 and 17 synthesis and HSG formation in cells. Chloramphenicol (100 mkg/ml) didn't influenoe these processes~ The signifioance of HSP synthesis in HSGformation is disoussed. of We thank Dr. D.Neumann (Institute Plant Biochemistry,GDR) for providing the antibodies to make possible this work. P168
P165
LIPID BODY ACCUMULATION IN NITROGENFIXING ROOT NODULES OF PEANUT
Arya, K. Bal, Abubaker M. Siddique, Department of Biology, Memorial University of Newfoundland, St. John's, NF Canada AlB 3X9. Nitrogen-fixingpeanutnodules are characterized by the presence of lipid bodies (oleosomes) in the infected cells. (Bal et al Protoplasma 150, 1989). It has been suggested that they serve as a supplementary source of energy for the high energy demanding process of nitrogen fixation. In this investigation nodules induced by mutant strains of rhizobia, which are incapable of fixing nitrogen (fix-) have been studied with a view to understanding the functional significance of lipid bodies in the root nodules. Nodules at different stages of development were fixed for routine transmission electron microscopy. A special staining technique using p-phenylenediamine was employed to localize lipid bodies in plastic sections. Control preparations were made using lipid solvents to check for non-specific staining. measurements made using a Morphometric were digital analyser (Carl Zeiss MOP-3), and the number of lipid bodies and their % area in the cell were determined. In nodules induced by two fix- strains of rhizobia revealed 2-3 times snore lipid body accumulation than in the ones induced by the wild type, where nitrogen fixation occurs The accumulation of lipid bodies in vigorously. absence of nitrogen fixation indicates that they are utilized in the nitrogen reduction process. (Supported by Natural Sciences and Engineering Research Council of Canada).
EFFECTOF ENVIRONMENTAL STRESSES ON PLANT DELL ULTRASTRUCTURE Valentina Khokhlova, Svetlana Porfirova. Institute of Plant Physiology Aoad.of Soi. USSR, Botanicheskaya 35, Moscow, USSR We investigate the effect of heat (400), saline (0,5M NaCl), dehydration (0,5M mannitol) and wound stresses on cell ultrastructure end heat shock proteins (HSP) 70 and 17 kDa localization in tip root cells of Cucurbita pepo L. seedlings. These stresses induce unspecific and specific changes in cell ultrastructure. We were first to show that salinity, dehydration and wounding cause cytoplasmic stress granules (SO) formation as heat shock (HS) does. The morphology of SG depends on stress type, duration and severety. SG are transient structures which disappear during recovery period. Using immunogold techique we study cellular localization of HSP 70 and 17 kDa under various stresses (polyclonal antibodies to these HSP were courtesely presented US by dr. D.Neumann, Institute of Plant Biochemistry, GDR). SO formed under HS in pumpkin root cells are found to contain HSP 70 end 17 kDa,whereas SG formed under other stresses contain rather low quantities of these proteins. It is evidently that SG formed under ve,rious stresses have different protein composition but the phenomenon of their appeerenoe is universal plant response toward environmental stresses. Pm7
P166
Reports, Vol. 14, Abstracts Supplement
STARCH DETECTION
Canavalia
1990
AND DOSAGE IN DC.
Angelo Luiz Cortelazzo & Benedict0 Dept.Cell Biology - I.B. - UNICAMP 13081 - Campinas - SP - Brazil.
de Campos Vidal - C.P. 6109 -
reserves in To analyse the use of starch amyloplasts during the initial development of the plant species Canavalia ensiformis (L.)DC. and C. gladiata (Jacqmeasurements were made ?? variations in starch content of cotyledons at 0, 7, 14, 21 and 28 days after imbibing. The material was fixed, embedded in paraffin, sectioned ( 8 pm thick) and submitted to PAS reaction. The starch grains were counted for each cell and their area and volume calculated. Reserve material was also extracted and starch dosage measured for each of the development periods. The results for an area of approximately 400 pm'and a volume of 5,600 pm' showed that 4 grains per cell is the average number up to the 7th day of imbibing for G ensiformis and up to 14th day for C. gladiata. The quantity falls to almost zero after 21 or 28 days of respectively. Dosage measurements imbibing, revealed an initial content of 744 ma of starch oer seed ( 56% dry weight) in C. ensiformis and 2,394 mg per seed (53% dry weist.) in C. gladiata. This investiqation demonstrated the reEtion between number-of amyloplasts per cell and the the plants dosage (mg/g dry weight), and that consume about 98.5% of this reserve during development up to cotyledon abcision.
HEAT SHOONPROTEINS I&CALIZATION INLEAF CELLS OFIRILBIDOPSIS Svetlana Porfirova, Valentina Ehokhlova, Natalya Yu Nlyueva. Institute of Plant Physiology,Acad. of Sci. USSR, Botenicheskaya 35, Moecow, USSR The localization of heat shock proteins (HSP) in Arabidopsis thaliana leaf cells was studied with polyclonal antibodies raised again& HSP 70 and 17 kDa of tomato cell suspension culture using protein A-gold technique. High and low moleou3.ar weight HSP, immuuologiGally relative to tomato HSP 70 and 17 were looalized in nuclei and in cytoplasmic heat shook granules (HSG) under heat shock (37O). ml7 were mainly accumulated in HSG and HSP 70 in nuolei. The dynemios of HSG formation (37O) and their degradation in normal conditions (23OI was studied. Dependenoe of HSG formation on RNA end protein synthesis was oharacterized. Cordycepin (200 mkg/ml) inhibited the synthesis of HSP 17 and HSGformation, slightly reduce ted the synthesis of HSP 70 and didn't change its nuolesr looalization. Cycloheximide (IO mkg/ml) oompletly inhibited HSP 70 and 17 synthesis and HSG formation in cells. Chloramphenicol (100 mkg/ml) didn't influenoe these processes~ The signifioance of HSP synthesis in HSGformation is disoussed. of We thank Dr. D.Neumann (Institute Plant Biochemistry,GDR) for providing the antibodies to make possible this work. P168