Boguslavskaya L.V.
Researche institute of biology,
Oles Honchar Dnepropetrovsk National University
Protein system of meristematic cells of
roots under the combined effect of cadmium ions and soil herbicide
Herbicides
contribute significantly to the economics of each country. Today, they are the
integral part of modern agricultural industry. However, their intensive use for
agricultural crops treatment causes the addition of herbicide compound to the metabolic process of cultivated
plants [1]. It should be noted that there is largely combined influence of
substances of anthropogenic origin on plant facilities in natural environment.
If toxic effect of single ingredients of pollution has been fully examined,
then information about simultaneous effect of one or more stressors on one or
more physiological and biochemical systems of cultivated plants in process of
individual evolution was restricted [2]. The present research is extremely
important as the amount of pollutants in officially stated concentrations doesn’t
produce toxic effects in plants on organismic and tissular levels but may
appear on cellular level. The objects of laboratory research were roots of
two-day germs of three-linear middle-early hybrid of Byelozerskiy 295 SV that
were cultivated in cadmium nitrate medium in the strength of 50, 100 and 500 µM
and herbicidal preparation of chloroacetonilide dual group (metolachlor) in the
strength of 1 mg/l and their blend (1 mg/l of metolachlor + 50 µM Cd2+).
The polypeptide structure of cytoplasmic protein was analyzed in meristematic
cells of two-day maze roots by SDS- electrophoresis method
[3]. Their molecular mass (Mr, kD) and abundance (%) were
determined. The entry of cadmium ions and metolachlor into the cell has evoked
the reaction chain which caused synthesis of specific polypeptides as well as
material alterations in accumulation of standard proteins (table 1). Thus, the
emergence of protein with molecular weight equal to 27 kD was characteristic of
polypeptide structure of cytoplasmic proteins of maze root meristem which was
exposed to the cadmium ions, metolachlor and their mixture. But its content was
variable from 0,01% (500 µM Cd2+) to 9,3% (100 µM Cd2+)
according to species and concentration of toxicant.
Table
1
Molecular mass and abundance of easily soluble
proteins of root meristhem cells of
maize germs under the cadmium ions and herbicide effect
|
Valua Mr, кД |
Blanc |
(Cd(NO3)2 × 4 Н2О, mМ |
metolachlor, 1 мг/л |
Cd2+(50mМ)+metolachlor, (1 мг/л) |
||
|
50 |
100 |
500 |
||||
|
Peptide abundance, % |
||||||
|
97.8 |
0,43 |
0,3 |
0,01 |
0,41 |
3,41 |
- |
|
83.2 |
- |
- |
1,16 |
0,37 |
- |
- |
|
81.3 |
5,96 |
21,02 |
- |
5 |
7,33 |
5,25 |
|
79.5 |
0,28 |
3,02 |
5,51 |
- |
1,4 |
7,46 |
|
77.7 |
- |
- |
1,02 |
1,52 |
3,2 |
- |
|
75.9 |
3,22 |
3,19 |
- |
1,52 |
- |
- |
|
74.2 |
0,48 |
2,19 |
7,15 |
0,83 |
11,22 |
9,15 |
|
70.8 |
0,43 |
2,1 |
0,31 |
0,37 |
5,48 |
3,47 |
|
66.1 |
1,79 |
2,14 |
0,49 |
1,89 |
1,02 |
1,36 |
|
64.6 |
1,6 |
6 |
1,66 |
0,92 |
8,4 |
0,83 |
|
61.7 |
1,00 |
- |
- |
- |
- |
1,14 |
|
60.3 |
0,3 |
1,78 |
4,12 |
1,58 |
0,36 |
2,07 |
|
58.9 |
1,33 |
1 |
1,24 |
4,06 |
1,42 |
1,26 |
|
55.0 |
9,23 |
5,34 |
4,75 |
6,17 |
4,87 |
0,07 |
|
49.0 |
27,63 |
28,48 |
21,43 |
23,76 |
27,37 |
31,21 |
|
47.9 |
2,47 |
0,58 |
0,61 |
1,68 |
0,1 |
- |
|
46.8 |
0,49 |
1,55 |
0,24 |
0,52 |
0,25 |
0,07 |
|
45.8 |
3,94 |
6,32 |
3,03 |
2,44 |
6,89 |
12,02 |
|
44.7 |
0,93 |
1,5 |
8,1 |
13,94 |
- |
- |
|
43.7 |
9,14 |
6,93 |
8,83 |
0,26 |
1,33 |
2,8 |
|
41.7 |
0,39 |
0,06 |
1,41 |
0,27 |
1,89 |
0,92 |
|
39.9 |
1,74 |
- |
- |
5,16 |
2,43 |
3,24 |
|
39.0 |
3,66 |
- |
- |
8,93 |
- |
- |
|
34.7 |
3,64 |
1,32 |
- |
- |
0,44 |
3,26 |
|
31.7 |
19,92 |
3,64 |
19,61 |
18,39 |
10,93 |
13,09 |
|
27.0 |
- |
1,54 |
9,32 |
0,01 |
0,26 |
1,33 |
But
its content was variable from 0,01% (500 µM Cd2+) to 9,3% (100 µM Cd2+)
according to species and concentration of toxicant. Polypeptide synthesis with
molecular weight equal to 77,7 kD was noted under separate effect of two
cadmium nitrate concentrations (100 and 500 µM) and metolachlor, its content
was high in the latter case. Synthesis de novo polypeptide with molecular
weight equal to 83,2 kD was determined at a medium and high concentration of
cadmium ions. Synthesis of stressed proteins was observed against the
background of abrupt decrease or complete stop of synthesis of normal proteins.
Thus,
it was noted the essential accumulation of polypeptide with molecular weight
equal to 74,2 kD under the effect of all treatment variants of plants. Its
highest content was noted under separate effect of herbicide and joint
influence of xenobiotics (23 and 19 times higher than in control).
Combined
content of stressed proteins at the
lowest concentration of cadmium was 1,55, medium – 11,55 and the highest –
1,3%. The essential accumulation of polypeptide with molecular weight equal to
79,5 kD (27 times higher than in control) was found to be the characteristic
feature of combined effect of xenobiotics.
Thus,
common tendency of cells reaction of root meristem of maize germs at 48-hours
effect of cadmium, soil herbicide and their blend is depression of synthesis of
normal proteins and increase of stressed ones. Character of synthesis of
stressed polypeptides can be determined by nature of xenobiotic and depends on
its concentration in growth medium.
Literature:
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2. Глубока В.М. Зміни
компонентів ліпідного обміну за умов дії на рослини кукурудзи іонів важких
металів та гербіцидів: автореф. дис. кандидата біол.. наук: спец. 03.00.12. – Київ, 2007. – 16 с.
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the head of bacteriophage T4 // Nature. – 1970. – Vol. 227, № 52-59. – P. 680.