3 research outputs found
A modified method of total RNA isolation and quantitative analysis of superoxide dismutase gene expression from different organs of Ipomoea carnea
Ipomoea carnea (I. carnea) has unique biological features for the study of cellular and molecular adaptation mechanisms due to presence of diverse alkaloid and its cadmium tolerance capacity. The present study was directed to quantify total SOD content in different organs of the plant and further extended to relative quantification of cytosolic CuZn-SOD, Fe-SOD and Mn-SOD mRNA. A modified method of total RNA isolation from the plant I. carnea which is rich in alkaloids has been described. Total SOD content of apical and lateral bud was highest, but transcript abundance of cytosolic CuZn-SOD was much lower as compared to root and leaves. In these cases Mn- and Fe-SOD mRNA was relatively higher and perhaps that was contributing to the high SOD activity. However, less photosynthetically active organs like root and petal show less SOD activity but mRNA level of cytosolic CuZn-SOD was competitive in these cases. The results showed that SODs in different compartments are differently regulated and each SOD isoenzyme must be performing specific function related to its cellular localization and expression of the protein isoforms depend upon local accumulation of superoxide
Superoxide dismutase-mentor of abiotic stress tolerance in crop plants
Abiotic stresses impact growth, development,
and productivity, and significantly limit the global agricultural
productivity mainly by impairing cellular
physiology/biochemistry via elevating reactive oxygen
species (ROS) generation. If not metabolized, ROS
(such as O2
•−, OH•, H2O2, or 1O2) exceeds the status
of antioxidants and cause damage to DNA, proteins,
lipids, and other macromolecules, and finally cellular
metabolism arrest. Plants are endowed with a family
of enzymes called superoxide dismutases (SODs) that
protects cells against potential consequences caused by
cytotoxic O2
•− by catalyzing its conversion to O2 and
H2O2. Hence, SODs constitute the first line of defense
against abiotic stress-accrued enhanced ROS and its reaction
products. In the light of recent reports, the present
effort: (a) overviews abiotic stresses, ROS, and their
metabolism; (b) introduces and discusses SODs and
their types, significance, and appraises abiotic stressmediated
modulation in plants; (c) analyzes major reports
available on genetic engineering of SODs in
plants; and finally, (d) highlights major aspects so far
least studied in the current context. Literature appraised
herein reflects clear information paucity in context with
the molecular/genetic insights into the major functions
(and underlying mechanisms) performed by SODs, and
also with the regulation of SODs by post-translational
modifications. If the previous aspects are considered in
the future works, the outcome can be significant in sustainably
improving plant abiotic stress tolerance and efficiently
managing agricultural challenges under changing
climatic conditions