Comparative and evolutionary analysis of α-amylase gene across monocots and dicots

α-amylase is an important enzyme involved in starch degradation to provide energy to the germinating seedling. The present study was conducted to reveal structural and functional evolution of this gene among higher plants. Discounting polyploidy, most plant species showed only a single copy of the gene making multiple isoforms in different tissues and developmental stages. Genomic length of the gene ranged from 1472 bp in wheat to 2369 bp in soybean, and the size variation was mainly due to differences in the number and size of introns. In spite of this variation, the intron phase distribution and insertion sites were mostly conserved. The predicted protein size ranged from 414 amino acid (aa) in soybean to 449aa in Brachypodium. Overall, the protein sequence similarity among orthologs ranged from 56.4 to 97.4 %. Key motifs and domains along with their relative distances were conserved among plants although several species, genera, and class specific motifs were identified. The glycosyl hydrolase superfamily domain length varied from 342aa in soybean to 384aa in maize and sorghum while length of the C-terminal β-sheet domain was highly conserved with 61aa in all monocots and Arabidopsis but was 59aa in soybean and Medicago. Compared to rice, 3D structure of the proteins showed 89.8 to 91.3 % similarity among the monocots and 72.7 to 75.8 % among the dicots. Sequence and relative location of the five key aa required for the ligand binding were highly conserved in all species except rice.     

Comparison of Copy Number of HSF Genes in Two Buffalo Genomes

The copy number variation (CNV) is the number of copies of a particular gene in the genotype of an individual. Recent evidences show that the CNVs can vary in frequency and occurrence between breeds. These variations reportedly allowed different breeds to adapt to different environments. As copy number variations follow Mendelian pattern of inheritance, identification and distribution of these variants between populations can be used to infer the evolutionary history of the species. In this study, we have examined the absolute copy number of four Heat shock factor genes viz. HSF-1, 2, 4, and 5 in two different breeds of buffalo species using real-time PCR. Here, we report that the absolute copy number of HSF2 varies between the two breeds. In contrast no significant difference was observed in the copy number for HSF-1, 4, and 5 between the two breeds. Our results provide evidence for the presence of breed specific differences in HSF2 genomic copy number. This seems to be the first step in delineating the genetic factors underlying environmental adaptation between the two breeds. Nevertheless, a more detailed study is needed to characterize the functional consequence of this variation.     

Genetic Manipulation of Leishmania donovani to Explore the Involvement of Argininosuccinate Synthase in Oxidative Stress Management

Reactive oxygen and nitrogen species (ROS and RNS) produced by the phagocytic cells are the most common arsenals used to kill the intracellular pathogens. However, Leishmania, an intracellular pathogen, has evolved mechanisms to survive by counterbalancing the toxic oxygen metabolites produced during infection. Polyamines, the major contributor in this anti-oxidant machinery, are largely dependent on the availability of L-arginine in the intracellular milieu. Argininosuccinate synthase (ASS) plays an important role as the rate-limiting step required for converting L-citrulline to argininosuccinate to provide arginine for an assortment of metabolic processes. Leishmania produce an active ASS enzyme, yet it has an incomplete urea cycle as it lacks an argininosuccinate lyase (ASL). There is no evidence for endogenous synthesis of L-arginine in Leishmania, which suggests that these parasites salvage L-arginine from extracellular milieu and makes the biological function of ASS and the production of argininosuccinate in Leishmania unclear. Our previous quantitative proteomic analysis of Leishmania promastigotes treated with sub-lethal doses of ROS, RNS, or a combination of both, led to the identification of several differentially expressed proteins which included ASS. To assess the involvement of ASS in stress management, a mutant cell line with greatly reduced ASS activity was created by a double-targeted gene replacement strategy in L. donovani promastigote. Interestingly, LdASS is encoded by three copies of allele, but Western blot analysis showed the third allele did not appear to express ASS. The free thiol levels in the mutant LdASS^-/-/+ cell line were decreased. Furthermore, the cell viability in L-arginine depleted medium was greatly attenuated on exposure to different stress environments and was adversely impacted in its ability to infect mice. These findings suggest that ASS is important for Leishmania donovani to counterbalance the stressed environments encountered during infection and can be targeted for chemotherapeutic purpose to treat visceral leishmaniasis.     

Next generation sequencing of Apis mellifera syriaca identifies genes for Varroa resistance and beneficial bee keeping traits

Apis mellifera syriaca exhibits a high degree of tolerance to pests and pathogens including varroa mites. This native honey bee subspecies of Jordan expresses behavioral adaptations to high temperature and dry seasons typical of the region. However, persistent honey bee imports of commercial breeder lines are endangering local honey bee population. This study reports the use of next‐generation sequencing (NGS) technology to study the A. m. syriaca genome and to identify genetic factors possibly contributing toward mite resistance and other favorable traits. We obtained a total of 46.2 million raw reads by applying the NGS to sequence A. m. syriaca and used extensive bioinformatics approach to identify several candidate genes for Varroa mite resistance, behavioral and immune responses characteristic for these bees. As a part of characterizing the functional regulation of molecular genetic pathway, we have mapped the pathway genes potentially involved using information from Drosophila melanogaster and present possible functional changes implicated in responses to Varroa destructor mite infestation toward this. We performed in‐depth functional annotation methods to identify ～600 candidates that are relevant, genes involved in pathways such as microbial recognition and phagocytosis, peptidoglycan recognition protein family, Gram negative binding protein family, phagocytosis receptors, serpins, Toll signaling pathway, Imd pathway, Tnf, JAK‐STAT and MAPK pathway, heamatopioesis and cellular response pathways, antiviral, RNAi pathway, stress factors, etc. were selected. Finally, we have cataloged function‐specific polymorphisms between A. mellifera and A. m. syriaca that could give better understanding of varroa mite resistance mechanisms and assist in breeding. We have identified immune related embryonic development (Cactus, Relish, dorsal, Ank2, baz), Varroa hygiene (NorpA2, Zasp, LanA, gasp, impl3) and Varroa resistance (Pug, pcmt, elk, elf3‐s10, Dscam2, Dhc64C, gro, futsch) functional variations genes between A. mellifera and A. m. syriaca that could be used to develop an effective molecular tool for bee conservation and breeding programs to improve locally adapted strains such as syriaca and utilize their advantageous traits for the benefit of apiculture industry.     

Induction of carcinoembryonic-antigen-gene expression in human colorectal carcinoma by sodium butyrate.

The ability of the insulin-induced phospho-oligosaccharide to stimulate amino acid transport was studied in isolated rat hepatocytes. At low alpha-aminoisobutyric acid concentrations (0.1 mM), both 100 nM-insulin and 10 microM-phospho-oligosaccharide doubled amino acid uptake after 2 h of incubation. This stimulation was prevented by 0.1 mM-cycloheximide or 5 micrograms of actinomycin D/ml, indicating that the phospho-oligosaccharide, like insulin, was acting via the synthesis of a high-affinity transport component. The effects of the phospho-oligosaccharide and of insulin were blocked by Ins2P (2.5 mM), but not by myo-inositol, inositol hexaphosphoric acid or several monosaccharides such as mannose, glucosamine and galactose. Both the temporal effect on amino acid entry and the extent of stimulation of this process by the phospho-oligosaccharide indicate that this molecule mimics, and may mediate, some of the long-term actions of insulin. However, the effects of phospho-oligosaccharide and insulin were not exactly the same, since the effect of insulin, but not of the phospho-oligosaccharide, was additive with that of glucagon.     

The effect of some pesticides in conjunction with nitrogen sources on growth and carbohydrate and nitrogen constituents of sugarcane during formative phase

Summary The effect of gamma isomer of benzene hexachloride and Telodrin both in absence and presence of ammonium and nitrate nitrogen carriers on shoot and root growth and carboydrate and nitrogen constituents of sugarcane was studied. The pesticides induced shoot emergence and development of tillers and roots. Shoot growth, nitrogen intake and insoluble nitrogen content invariably increased by pesticide application while soluble carbohydrate and soluble nitrogen content of the shoot decreased. Pesticides also increased the water-soluble nitrate content of the soil.The effect of pesticides was not confined to ammonical source of nitrogen rather the pesticides proved equally effective under nitrate source of nitrogen and also in absence of additional nitrogen. Beneficial effect of pesticides on growth and development of sugarcane appears largely on account of more efficient utilisation of soil and fertilizer nitrogen. The results raise an interesting possibility of using these pesticides as growth stimulators to increase the efficiency of sugarcane plants growing under sub-optimal conditions of nitrogen     

Leakage of electrolytes and phenols and altered activity profile of peroxidase and its isoenzymes from wheat leaves inoculated withPuccinia recondita

Second and third leaves of 25-day old wheat (Triticum aestivum L.) planta, cultivar WL-711, were inoculated with three races of the brown rust pathogen,Puccinia recondita f. sp.tritici. The host reflected a differential interaction response towards these races, viz., susceptible reaction to race 77 (reaction type 4) intermediate reaction to race 104 (reaction type 1 - 3) and resistant reaction to race 63 (reaction type 0). Post-inoculation mutual interaction brought about observable changes in peroxidase activity along with leakage of electrolytes and phenolic constituents indicating altered permeability of host tissue. Differential increase in leakage of electrolytes and phenols occurred with increase of peroxidase activity during 12 h and 24 h post-inoculation, however, during 36 h, 48 h and 72 h post-inoculation, electrolyte leakage increased continuously with corresponding increases in peroxidase activity in all three interactions, while leakage of phenols showed a differential pattern. The differential changes in isoenzymic pattern of peroxidase activity were also noted during the progressive infection process which may also be an indication of altered permeability of the host issue at the very onset of brown rust infection.     

Biosurfactant production by Pseudomonas sp. and its role in aqueous phase partitioning and biodegradation of chlorpyrifos

Aim:  To study the effect of biosurfactant on aqueous phase solubility and biodegradation of chlorpyrifos.
Methods and Results:  A Pseudomonas sp. (ChlD), isolated from agricultural soil by enrichment culture technique in the presence of chlorpyrifos, was capable of producing biosurfactant (rhamnolipids) and degrading chlorpyrifos (0·01 g l⁻¹). The partially purified rhamnolipid biosurfactant preparation, having a CMC of 0·2 g l⁻¹, was evaluated for its ability to enhance aqueous phase partitioning and degradation of chlorpyrifos (0·01 g l⁻¹) by ChlD strain. The best degradation efficiency was observed at 0·1 g l⁻¹ supplement of biosurfactant, as validated by GC and HPLC studies.
Conclusion:  The addition of biosurfactant at 0·1 g l⁻¹ resulted in more than 98% degradation of chlorpyrifos when compared to 84% in the absence of biosurfactant after 120-h incubation.
Significance and Impact of the Study:  This first report, to the best of our knowledge, on enhanced degradation of chlorpyrifos in the presence of biosurfactant(s), would help in developing bioremediation protocols to counter accumulation of organophosphates to toxic/carcinogenic levels in environment.     

Neuroendocrine control of oocyte development in Poecilocera picta (Insecta: Orthoptera)

The neuroendocrine control of oocyte development in Poecilocera picta Fab. has been described. The secretory activity of the A type of neurosecretory cells has been correlated with ovarian development. In P. picta during the first four days after emergence the neurosecretory material is seen passing down the axons but the cells are largely devoid of neurosecretory material. When the oocytes are developed the A type cells are with stored neurosecretory material.
In P. picta the mature males do not appear to accelerate the process of maturation in females. The females which are reared without males or with castrated males also mature at the same time as the females which are reared with males. The corpus allatum also enlarges and decreases at the same period. The number of resorptive bodies is much more in the females which are reared with castrated males or without males. There appears to be some correlation in the secretion of the neurosecretory material, copulation, and the appearance of resorptive bodies. In P. picta the role of the mature male is only in copulation which very likely allows the cell to synthesize and secrete and release a large amount of neurosecretory material whose discharge in the haemolymph enables a successful development of the oocyte. Corpus allatum appears to be controlled by a precursor from the brain.
Cautery of the cerebral neurosecretory cells, allatectomy and sectioning of the nerves have been done to find out the role of neurosecretory material.