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This paper surveys the major developments in the field of consumer protection in India since 1984, when the statutory provisions for regulating unfair trade practices were incorporated for the first time.

In view of its adverse effect on consumer welfare, misleading advertising is sought to be regulated in most of the countries of the world. This note presents the legal provisions and institutional framework that regulate misleading advertisements in our country such as the MRTP Act, the Consumer Protection. Act, etc.

Cytokinesis in a plant cell is accomplished by the formation of a cell plate in the center of the phragmoplast. Little is known of the molecular events associated with this process. In this study, we report the identification of a dynamin-like protein from soybean and demonstrate that this protein is associated with the formation of the cell plate. Plant dynamin-like (PDL) protein contains 610 amino acids showing high homology with other members of the dynamin protein family. Western blot experiments demonstrated that it is associated with the non-ionic detergent-resistant fraction of membranes. Indirect immunofluorescence microscopy localized PDL to the cell plate in dividing soybean root tip cells. Double labeling experiments demonstrated that, unlike phragmoplast microtubules which are concentrated on the periphery of the forming plate, PDL is located across the whole width of the newly formed cell plate. Based on the temporal and spatial organization of PDL in the phragmoplast, we termed this protein 'phragmoplastin'. The data suggest that phragmoplastin may be associated with exocytic vesicles that are depositing cell plate material during cytokinesis in the plant cell.

Proline (Pro) accumulation has been correlated with tolerance to drought and salinity stresses in plants. Therefore, overproduction of Pro in plants may lead to increased tolerance against these abiotic stresses. To test this possibility, we overexpressed in tobacco the mothbean [delta]-pyrroline-5-carboxylate synthetase, a bifunctional enzyme able to catalyze the conversion of glutamate to [delta]-pyrroline-5-carboxylate, which is then reduced to Pro. The transgenic plants produced a high level of the enzyme and synthesized 10- to 18-fold more Pro than control plants. These results suggest that activity of the first enzyme of the pathway is the rate-limiting factor in Pro synthesis. Exogenous supply of nitrogen further enhanced Pro production. The osmotic potentials of leaf sap from transgenic plants were less decreased under water-stress conditions compared to those of control plants. Overproduction of Pro also enhanced root biomass and flower development in transgenic plants under drought-stress conditions. These data demonstrated that Pro acts as an osmoprotectant and that overproduction of Pro results in the increased tolerance to osmotic stress in plants.

One of the amazing features of the cellular machinery is that all organeller and membrane proteins, as well as those destined for secretion, have an attached address label for targeting to a specific site. Following synthesis, these proteins are folded, shipped, delivered, and received at the right compartment. Their assigned functions are performed only when they are properly placed at a designated site in the cell. Membrane vesicles play an essential role in protein transport as carriers of specific proteins to intracellular compartments. This process begins immediately after perception of specific signals and involves membrane ruffling, budding and transport of ER vesicles, fusion and passage through the Golgi, and release of vesicles from trans-Golgi cisternae to target to the vacuoles and plasma membrane. The components of the vesicle-mediated protein trafficking system are not, however, well defined. It is not known what kind of biochemical principles are operative for unidirectional transport of vesicles. How are vesicles fused to the target compartment? Although much remains to be understood, many studies from yeast and mammalian systems have identified some key players in this pathway. Isolation of plant homologs of some of these proteins has confirmed that these steps are conserved in evolution and must involve well-defined reactions. We focus here on the relevance of small GTP-binding proteins in vesicle-mediated protein transport (for earlier reviews, see Balch, 1990; Bednarek and Raikhel, 1992; Pryer et al., 1992; Terryn et al., 1993; Zerial and Stenmark, 1993).

The peribacteroid membrane (PBM) in legume root nodules is derived from plasma membrane following endocytosis of Rhizobium by fusion of newly synthesized vesicles. We studied the roles of plant Rab1p and Rab7p homologs, the small GTP-binding proteins involved in vesicular transport, in the biogenesis of the PBM. Three cDNAs encoding legume homologs of mammalian Rab1p and Rab7p were isolated from soybean (sRab1p, sRab7p) and Vigna aconitifolia (vRab7p). sRab1p was confirmed to be a functional counterpart of yeast Ypt1p (Rab1p) by complementation of a yeast ypt1-1 mutant. Both srab1 and vrab7 genes are induced during nodulation with the level of vrab7 mRNA being 12 times higher than that in root meristem and leaves. This induction directly correlates with membrane proliferation in nodules. Antisense constructs of srab1 and vrab7, under a nodule-specific promoter (leghemoglobin, Lbc3), were made in a binary vector and transgenic nodules were developed on soybean hairy roots obtained through Agrobacterium rhizogenes-mediated transformation. Both antisense srab1 and vrab7 nodules were smaller in size and showed lower nitrogenase activity than controls. The antisense srab1 nodules showed lack of expansion of infected cells, fewer bacteroids per cell and their frequent release into vacuoles. In contrast, antisense vrab7 expressing nodules showed accumulation of late endosomal structure and multivesicular bodies in the perinuclear region. These data suggest that both Rab1p and Rab7p are essential for the development of the PBM compartment in effective symbiosis.

The symbiotic root nodule, an organ formed on leguminous plants, is a product of successful interactions between the host plant and the soil bacteria, Rhizobium spp. Plant hormones play an important role in the genesis of this organ. The hormonal balance appears to be modulated by the signals produced by bacteria. Many host genes induced during nodule organogenesis and the symbiotic state have beenidentified and characterized from several legumes

Ornithine delta-aminotransferase (OAT) is an important enzyme in proline biosynthetic pathway and is implicated in salt tolerance in higher plants. OAT transaminates ornithine to pyrroline 5-carboxylate, which is further catalyzed to proline by pyrroline 5-carboxylate reductase. The Vigna aconitifolia OAT cDNA, encoding a polypeptide of 48.1 kDa, was expressed in Escherichia coli and the enzyme was partially characterized following its purification using (NH(4))(2)SO(4) precipitation and gel filtration techniques. Optimal activity of the enzyme was observed at a temperature of 25 degrees C and pH 8.0. The enzyme appeared to be a monomer and exhibited high activity at 4mM ornithine. Proline did not show any apparent effect but isoleucine, valine and serine inhibited the activity when added into the assay mixture along with ornithine. Omission of pyridoxal 5'-phosphate from the reaction mixture reduced the activity of this enzyme by 60%. To further evaluate these biochemical observations, homology modeling of the OAT was performed based on the crystal structure of the ornithine delta-aminotransferase from humans (PDB code 1OAT) by using the software MODELLER6v2. With the aid of the molecular mechanics and dynamics methods, the final model was obtained and assessed subsequently by PROCHECK and VERIFY-3D graph. With this model, a flexible docking study with the substrate and inhibitors was performed and the results indicated that Gly106 and Lys256 in OAT are the important determinant residues in binding as they have strong hydrogen bonding contacts with the substrate and inhibitors. These observations are in conformity with the results obtained from experimental investigations.

Availability of water is the most important factor for crop productivity. A vast area (more than 50 million hectares) of agricultural land throughout the world suffers from recurring droughts, resulting in poor crop productivity (Carter, 1975). An equally large area of land is affected by high salinity. Even though irrigated agriculture has increased significantly during the past twenty years, the high capital cost of this process and the resulting increase in salinity is making this approach difficult to adopt. Furthermore, excessive irrigation is lowering the water tables, reducing water availability even more. Drought and salinity are formidable obstacles to the development of new varieties that can give sufficient yield under water stress conditions (Boyer, 1982). Some plants have evolved adaptations to water deficit and high salinity. These adaptations encompass a wide variety of plant characteristics (McCue and Hanson, 1990), including developmental and structural traits, time of flowering, rooting patterns, leaf waxiness, and physiological mechanisms such as the ability to exclude salt or the compartmentalization of ions within the cell (Binzel et al., 1988). Obviously, these are Multigenic traits, and most of them are determined by gene products that have not yet been characterized. The Multigenic nature of the phenotypes has thwarted attempts to characterize these mechanisms at the genetic level and has hindered efforts to produce osmotolerant plants by traditional breeding and somaclonal variations (Vasil, 1990). Among the biochemical traits in the adaptation of plants to water stresses, synthesis and accumulation of compatible osmolytes and changes in patterns of carbon and nitrogen metabolism are most important. Plants accumulate energy-rich metabolites under water stress; the most prevalent of these are proline and betaines (Yancey et al., 1982). Concentration of K+ and organic solutes (primarily polyols) has been shown to increase in direct proportion to changes in osmotic stress in many bacteria, algae, and higher plants. With the recent advances in genetic transformation of crop plants, genes encoding entire biosynthetic pathways or that augment the rate-limiting step in an adaptive process can now be transferred to any crop plant.

Tropical legumes, such as soybean and Vigna, transport fixed nitrogen as ureides. We have earlier demonstrated that glutamine produced in the host cell cytoplasm as a result of ammonia assimilation is not transported out of the infection zone and is funneled in to plastids of the infected cells where it is converted in to purines. These de novo synthesized purines are then exported to the uninfected cells of the infection zone and inner cortex of the nodule where they are oxidized into allantoin and allantoic acids (ureides) and transported to the shoot. This pathway of nitrogen assimilation is apparently more energy efficient in comparison to amides that are normally transported in temperate nodules. To understand the regulation of assimilation of reduced nitrogen through ureide synthesis, we cloned phosphoribosylpyrophosphate amidotransferase (PRPP-AT) gene from soybean and showed that its expression is regulated by glutamine. This was accomplished by fusing the promoter of this gene with GUS reporter and transfer to hairy roots of soybean. The transgenic hairy roots showed glutamine-induced expression of GUS. Since PRPP-AT gene controls the entire de novo purine biosynthesis understanding the mechanism of its regulation is important for our ability to modify nitrogen assimilation process. Purines also induce peroxisome proliferation in the uninfected cells and the synthesis of enzymes necessary for oxidation of purines.

The human population increases by between 93 to 95 million people annually and it is estimated that it will be about 8 billion by 2020 (Gore, 1993). As a result, there is a growing concern for the total world environment and the realisation that food production must be markedly increased during the next century. The optimistic view is that as nations become wealthier, they experience general economic security, improved education, and falling birthrates. If present trends continue, we can project a human population of about 11 billion in the next 100 years. This may not be the most ideal global community but the situation does demand that we find solutions to the various problems. The most fundamental problem will be feeding a population of this size.

The symbiotically reduced nitrogen is assimilated in the host cytoplasm with the help of cytosolic glutamine synthetase. We have shown that this enzyme is induced directly in response to ammonia. The glutamine formed in the cytoplasm is funneled to the plastids where it is converted to purines. The latter are synthesized via de novo biosynthesis pathway. The purines are then oxidized into ureides inside the uninfected cells of root nodules. We have demonstrated that the de novo purine biosynthesis pathway is induced prior to the onset of nitrogen fixation, apparently due to high demand for purines for DNA endoreduplication in the infected cells. We have also demonstrated that glutamine enhances the expression of PRAT gene, encoding the first enzyme of the pathway. Because the level of uricase increases prior to that of PRAT, it suggests that purine catabolism may begin prior to the increase in de novo purine biosynthesis and the commencement of nitrogen fixation. The access of purines, exported to the uninfected cells, apparently induce peroxisome proliferation for the oxidation of uric acid to ureides. We have demonstrated that purines are able to induce peroxisome proliferation in yeast. Using urate as a source of nitrogen, we have been able to isolate several yeast mutants defective in peroxisome proliferation/assembly. We have complemented one of these mutants with a soybean gene encoding a putative peroxisome proliferation transcriptional factor with similarity to G-box binding proteins. In addition, we have determined two independent pathways for the conversion of uric acid to ureides in root nodules and have isolated corresponding genes involved in these pathways.

Rhizobia in the infected cells of root nodules are compartmentalized inside a membrane, peribacteroid membrane (PBM), where they are differentiated into bacteroids and begin fixing nitrogen. Since bacteria are never free inside the plant cell during symbiosis, the PBM serves as an interface between the two organisms and its integrity is vital for symbiotic nitrogen fixation. As bacteria are released from the infection thread they are endocytosed by the plasma membrane of the host and this membrane proliferates to enclose bacteria individually or in a group to eight per envelope. This necessitates a tight coordination of PBM biogenesis with the bacterial cell division and the number of bacteroids per envelope reflects when cell division ceases following endocytosis. This event is determined by the host. Although derived from the plasma membrane (PM), the PBM undergoes significant chandes and becomes a mosaic membrane having properties in common with the vacuolar and the PM (Verma, 1992). Thus, vesicular traffic in root nodules must be unique to direct appropriate PBM nodulins and the peribacteroid fluid proteins to their proper sites. The plant genetics data (Tikhonovich et al., 1995) is consistent with this interpretation. The mechanism controlling PBM biogenesis and proliferation is poorly understood. Recent studies on plant and bacterial genetics have shed some lights on biogenesis of this compartment and suggest that both bacteria and the host plant control the synthesis of PBM and its effectiveness in symbiosis.

GS (EC 6.3.1.2) occupies a key position in controlling nitrogen metabolism, a pathway directly affecting plant productivity. It catalyzes the first step in the assimilation of ammonia in higher plants, converting inorganic ammonia produced by different metabolic routes into organic nitrogen. GS is encoded by a small gene family in higher plants, the members of which are expressed in different tissues, cell types, and subcellular compartments under the control of both metabolic status and developmental programs of the plant (Hirel et al., 1993). This temporal and spatial regulation of GS genes meets the requirements of ammonia assimilation under various physiological conditions. In legume-Rhizobium symbiosis, the symbiotically reduced ammonia is assimilated by host root nodule-specific and/or root/nodule-specific GS. Both nodule-specific (alfalfa, Dunn et al., 1988; and soybean, Roche et al., 1993) and nodule-enhanced (French bean, Cullimore et al., 1984) GS isoforms have been reported. In pea no nodule-specific GS has been found (Tingey et al., 1987). In addition to the nodule-specific GS, soybean also contains a root/nodule GS, the expression of which is strongly enhanced in nodules. The latter occurs in direct response to the availability of ammonia (Hirel et al., 1987; Mia0 et al., 1991). We report here the isolation of a full-length cDNA sequence encoding mothbean (Vigna aconitifolia) GS, expression of which appears to be nodule specific. Mothbean is a diploid tropical legume that can be easily transformed by Agrobacterium-mediated transformation methods (Lee et al., 1993) and regenerated (our unpublished results). Thus, mothbean is a plant of choice toward understanding the regulation and role of specific GS isoforms in plant nitrogen metabolism. Using a soybean cytosolic GS sequence (GS20; Mia0 et al., 1991) as a probe, we isolated severa1 GS cDNA sequences from a mothbean nodule cDNA library (Table I). One of these sequence, VGSn-1, contains an open reading frame of 1068 nucleotides and encodes a GS polypeptide of 356 amino acids. Sequence homology comparison showed that VGSn-1 shares more than 85% similarity at the amino acid level

Concomitant with the release of rhizobia from infection thread, rapid proliferation of endomembrane system occurs, which encloses the invading bacteria in a membrane envelope, peribacteroid membrane (PBM). Although derived from the plasma membrane, the PBM shares features common to both plasma membrane and vacuolar membrane and appears to be a mosaic membrane. We have initiated studies to search for plant genes involved in vectorial transport of proteins to PBM and the peribacteroid space. In yeast, several small GTP-binding proteins mediate protein transfer from the ER to the Golgi. We have isolated soybean homologs of yeast YPT1 and sarl genes and mammalian rab7 genes. The soybean YPT1 homolog (SOYPT1) was shown to complement a yeast ypt1 mutant. Transgenic nodules containing antisense SOYPT1 under a leghemoglobin (Lbc3) promoter were developed on soybean hairy roots. These nodules showed retarded growth and reduced nitrogen fixation activity. Early senesence of PBM occurs in these nodules releasing bacteria inside the vacuole. We have determined topology of a major PBM nodulin, nodulin-26, and have established minimum sequences required for targeting this protein to PBM. We have shown that expression of nodulin-26 gene is negatively controlled in soybean roots and this control is not operative in heterologous transgenic plants.

Nodulin-26 is an intrinsic membrane protein of the peribacteroid membrane in soybean root nodules. This protein contains six transmembrane domains and forms an ion channel translocating specific molecules to the bacteroids. We have determined the topology of this protein by co-translational processing and protease protection experiments. Our results suggest that the carboxy and amino termini of this protein face the cytoplasm while the glycosylation site at amino acid position 150 is located on the surface facing the bacteroids. Two transmembrane domains are sufficient for the integration of nodulin-26 into the membrane as revealed by deletion analysis. Nodulin-26 is phosphorylated by a kinase located in the peribacteroid membrane. The phosphorylation mechanism may allow nodulin-26 to be an active channel.

A highly coordinated activity of many bacterial and plant genes gives rise to an organ capable of housing Rhizobium and supporting the metabolic demands of symbiotic nitrogen fixation. Several host genes encoding nodule-specific proteins (nodulins) have been isolated and characterized from many legumes. Most of the early nodulin genes identified to date appear to encode structural proteins while the late nodulins mainly participate in the metabolic functions of nodules. The nodulin genes are derived from other plant genes encoding structural and metabolic proteins as they have similar functions or sequence homologies. However, the nodulin genes have come under the nodule developmental control in order to adapt to this unique organ. We have demonstrated that endocytosis release of Rhizobium is not necessary for the development of an organized nodule structure, suggesting that certain bacterial signals trigger the nodule developmental program prior to the release of bacteria inside the “infected” cells. Recent studies suggest that “physiological internalization” of the peribacteroid membrane compartment, housing the bacteria, is essential for the establishment of the symbiotic state. One of the nodulins, nodulin-26, is shown to play a critical role in this process. This nodulin forms an ion channel in the peribacteroid membrane. Symbiotically fixed nitrogen seems to be entering the host cell by diffusion, as all cells in the infection zone, delimited by the endodermis, have a uniform concentration of ammonia. The latter was determined by an ammonia-sensitive glutamine synthetase promoter linked with a reporter gene. Conversion of amides into ureides is essential in tropical legumes and several nodulins, including nodulin-35, are involved in this pathway.

A genetic locus in fast-growing Rhizobium japonicum (fredii) USDA 191 (Fix+ on several contemporary soybean cultivars) was identified by random Tn5 mutagenesis as affecting the development and differentiation of root nodules. This mutant (MU042) is prototrophic and shows no apparent alterations in its surface properties. It induces aberrant nodules, arrested at the same early level of differentiation, on all its host plants. An 8.1-kilobase EcoRI fragment containing Tn5 was cloned from MU042. In USDA 191 as well as another fast-growing strain, USDA 201, the affected locus was found to be unlinked to the large symbiotic plasmid and appears to be chromosomal. An analogous sequence has been shown to be present in Bradyrhizobium japonicum (J. Stanley, G.G. Brown, and D.P.S. Verma, J. Bacteriol. 163:148-154, 1985) as well as in R. trifolii and R. meliloti. MU042 was complemented for effective nodulation of soybean by a cosmid clone from USDA 201, and the complementing locus was delimited to a 6-kilobase EcoRI subfragment. An R. trifolii strain (MU225), whose indigenous symbiotic plasmid was replaced by that of strain USDA 191, induced more highly differentiated nodules on soybean than did MU042. This suggests that the mutation in MU042 can be functionally substituted by similar loci of other fast-growing rhizobia. Leghemoglobin and nodulin-35 (uricase II) were present in the differentiated Fix- nodules induced by MU225, whereas both were absent in MU042-induced pseudonodule structures.

Leghaemoglobin genes in soybean (Glycine max) are present as a moderately reiterated family of sequences. Since there are identical restriction site patterns of these sequences in DNA isolated from leaf, root, or nodule tissue, the data suggest that no major changes in the organization or methylation of leghaemoglobin genes occur during their induction. Cloned soybean leghaemoglobin–cDNA cross hybridized with RNA from root nodules of kidney bean (Phaseolus vulgaris), and to a lesser extent, of pea (Pisum sativum) indicating sequence homology in the leghaemoglobin genes of these species. Hybridization to the genomic DNA restriction fragments of two other species, Glycine soja and Vicia faba, also indicated interspecies sequence homologies. Several restriction fragments appear to be common to all the species examined. The induction of these genes occurs following infection of the plant by Rhizobium and is independent of the appearance of nitrogenase activity in the nodules. The level of expression is, however, influenced by various mutations in Rhizobium that result in the development of ineffective (nonnitrogen fixing) nodules.

Having attained self-sufficiency in food production, India is now concentrating in using wastelands to increase its production of other products of agroforestry namely, fodder, fuel and small timber for the poorer section of society. Many agroforestry practices are being tried towards the attainment of this goal. In one such attempt, a 4 ha plantation was established in 1974 on Community grazing land in the village of Dhanori in Gujarat as a part of the State Village Forests Scheme. Casuarina equisetifolia was planted beca se it suited the site and because the villagers wished it. Grasses grew up naturally as a result of the enclosure. The trees were felled in 1983–4 and the distribution of benefits determined by the village panchayat. The internal Rate of Return was 35%. Villagers benefited from grasses, fuelwood and small timber for house construction and repair and from the employment generated. The success of the project led the village to organize itself into a Tree Grower's Society and undertake further planting in 1985–6. The demonstrated efficiency of the woodlot let to 200 ha of other plantations being established in the area. the poor benefited considerably from the project but if they had a greater say in the deliberations of the panchayat, the benefits could have been even greater. this agroforestry system has the potential of increasing the production of grasses, fuelwood, small timber and fruits (food) from wastelands.

A suspension culture obtained from peanut (Arachis hypogaea L.) cotyledons was passed through three standard sieves of 0.15, 0.5, and 2.0 mm and the subsequent four fractions were studied for morphological differences and molecular heterogeneity in peroxidase isozymes. Quantitative and qualitative differences occur in this enzyme between groups of cells of different sizes. The appearance of two new peroxidase isozymes is correlated with cellular differentiation as the cell mass enlarges from 0.5 to 4.0 mm in diameter.

Treatment of soybean root nodule tissue with a nonionic detergent, Nonidet P-40, after aldehyde fixation, results in a selective solubilization of membranes. The cell wall membrane of bacteroids and of free-living Rhizobium is resistant to this treatment. Fragments of "extra" membrane present inside the membrane envelope enclosing the bacteroids are also resistant to the detergent and are morphologically similar to the outer membrane of the cell wall of Rhizobium grown in broth culture. These observations, along with electrophoretic profiles of detergent resistant membranes from nodules, free-living Rhizobium, and isolated nodule bacteroids, suggest that the Rhizobium cell wall membrane undergoes significant changes during establishment of the root nodule symbiosis.

The advent of recombinant DNA technology has enabled the isolation of virtually any gene; indeed, the construction of complete gene libraries from any given organism is now routine. However, in many instances, it is extremely difficult to ascertain the biological function of a cloned gene sequence. Similarly, it is difficult to isolate a gene with a known phenotype for which there is no biochemical marker, e.g., a gene(s) affecting the shape or size of an organ.

The legume-Rhizobium endosymbiosis may be the most highly evolved and perhaps ultimate association between a microbe and a plant in which the two partners can still grow independently. Undoubtedly the strong selective pressure on this association is the resulting nutritional complementation: the plant can be considerd a carbon-rich, nitrogen-deficient phototroph and the Rhizobium a carbon-deficient, nitrogen-fixing heterotroph. The resulting symbiosis which occurs in a specialized organ, the root nodule, makes the plant autotrophic with respect to the availability of reduced nitrogen, a limiting factor in plant nutrition. This unique intracellular association contributes significantly towards the yield of the agriculturally important legume crops.

In a suspension culture of peanut cotyledons (Arachis hypogaea L.) the rate of protein synthesis decreased as the cell mass increased in diameter, with a decrease in free amino acids except in a cell mass of 0.15–0.5 mm. A high level of catalase and low level of peroxidase activity was related to a higher rate of protein synthesis in single cell ( 0.5 mm in diameter. Another peroxidase isozyme appeared in a cell mass of 2–4 mm in diameter. Quantitatively there was a significant increase in peroxidase with a decrease in catalase activity between cell clumps of increasing sizes.

WE report here the isolation from messenger-free 80S wheat embryo ribosomes of 40S and 60S ribosomal subunits active in protein synthesis directed by natural messenger RNA (Table 1). This has enabled us to provide firm biochemical evidence satisfying the hypothesis that initiation in eukaryotic cells proceeds through the formation of a 40S ribosomal subunit-mRNA-Met-tRNA complex (complex I) which subsequently combines with a 60S ribosomal subunit to form an 80S monoribosome (complex II) functional in protein synthesis.

Protein synthesis and respiration of 3 day old V-56R peanut (Arachis hypogaea, L.) cell-suspension cultures are reduced to 45-55% of controls immediately after a massive dose (500 Krad) of radiation. However, they apparently recovered during 3-4 days of postirradiation period. Recovery in protein synthesis and respiration continued and exceeded the control levels one week after radiation. Analysis of the proteins synthesized during the postirradiation period indicated that the distribution of radioactivity in labeled proteins is changed and large molecular weight proteins are directly or indirectly broken down to low molecular weight fractions. A significant increase in endogenous free amino acids is observed during the postirradiation period. Both respiration and protein synthesis started to decline 2 weeks after irradiation and levelled well below the controls during subsequent postirradiation period. Although quantitatively protein synthesis showed an apparent recovery after massive irradiation, the pr...

The growth of V-56R peanut (Arachis hypogaea, L.) cell-suspension cultures was inhibited as a function of dose (5-500 krad) of radiation, however, protein synthesis showed an immediate response only after a dose of more than 50 krad. Morphological observations made on the irradiated cells indicated that while cell division is completely arrested after a dose of 50-500 krad, cell expansion seems to be least affected and 50-60% cells become large filamentous giant cells. The frequency of giant cells increased during postirradiation period of 4-5 weeks. Radiation-induced giant cells showed an active cyclosis, denser cytoplasm and higher number of starch grains. Protein synthesis continued even after a massive dose (500 krad) of radiation at approximately 45-55% of controls, if the cells were incubated in fresh medium after irradiation, and showed an apparent recovery during postirradiation period. The effect of radiation on protein synthesis was also dependent on the age of the cultures and presence of condi...