The B-Cell Specific Transcription Factor, Oct-2, Promotes Epstein-Barr Virus Latency by Inhibiting the Viral Immediate-Early Protein, BZLF1

The Epstein-Barr virus (EBV) latent-lytic switch is mediated by the BZLF1 immediate-early protein. EBV is normally latent in memory B cells, but cellular factors which promote viral latency specifically in B cells have not been identified. In this report, we demonstrate that the B-cell specific transcription factor, Oct-2, inhibits the function of the viral immediate-early protein, BZLF1, and prevents lytic viral reactivation. Co-transfected Oct-2 reduces the ability of BZLF1 to activate lytic gene expression in two different latently infected nasopharyngeal carcinoma cell lines. Furthermore, Oct-2 inhibits BZLF1 activation of lytic EBV promoters in reporter gene assays, and attenuates BZLF1 binding to lytic viral promoters in vivo. Oct-2 interacts directly with BZLF1, and this interaction requires the DNA-binding/dimerization domain of BZLF1 and the POU domain of Oct-2. An Oct-2 mutant (Δ262–302) deficient for interaction with BZLF1 is unable to inhibit BZLF1-mediated lytic reactivation. However, an Oct-2 mutant defective for DNA-binding (Q221A) retains the ability to inhibit BZLF1 transcriptional effects and DNA-binding. Importantly, shRNA-mediated knockdown of endogenous Oct-2 expression in several EBV-positive Burkitt lymphoma and lymphoblastoid cell lines increases the level of lytic EBV gene expression, while decreasing EBNA1 expression. Moreover, treatments which induce EBV lytic reactivation, such as anti-IgG cross-linking and chemical inducers, also decrease the level of Oct-2 protein expression at the transcriptional level. We conclude that Oct-2 potentiates establishment of EBV latency in B cells

Exploitation of pearl millet germplasm for identification of low grain phytate containing parental line

The present study was carried out to identify low grain phytate containing pearl millet parental lines amongst advanced inbred lines and designated B-line (counterpart of CMS lines) . A total number of 92 lines (46 each of inbreds and designated B line) were grown in a randomized block design with two replications during kharif-2013 and 33 selected (14 inbreds and 19 designated B-lines) from kharif-2013 were grown in kharif-2014 as well. Analysis of variance indicated significant differences between the tested genotypes during both the seasons. the phytate content varied from 4.45 to 6.80 mg/g and 1.31 to 6.19 mg/g during kharif-2013 in advanced inbred lines and designated B-lines respectively. Almost similar results were observed during kharif-2014, except the like with 1.31 mg/g phytate content during kharif-2013 was not stable and in kharif -2014, the phytate content for this line was 6.87 mg/g. Since none of the genotype screened showed low phytate content, therefore a large number of breeding lines are needed to be tested to know their genetic potential for low phytate

Not Available

Not AvailableThe present study was carried out to identify low grain phytate containing pearl millet parental lines amongst advanced inbred lines and designated B-line (counterpart of CMS lines) . A total number of 92 lines (46 each of inbreds and designated B line) were grown in a randomized block design with two replications during kharif-2013 and 33 selected (14 inbreds and 19 designated B-lines) from kharif-2013 were grown in kharif-2014 as well. Analysis of variance indicated significant differences between the tested genotypes during both the seasons. the phytate content varied from 4.45 to 6.80 mg/g and 1.31 to 6.19 mg/g during kharif-2013 in advanced inbred lines and designated B-lines respectively. Almost similar results were observed during kharif-2014, except the like with 1.31 mg/g phytate content during kharif-2013 was not stable and in kharif -2014, the phytate content for this line was 6.87 mg/g. Since none of the genotype screened showed low phytate content, therefore a large number of breeding lines are needed to be tested to know their genetic potential for low phytate.Not Availabl

Not Available

Not AvailableFlag leaves play an important role in synthesis and translocation of photo-assimilates in the pearl millet plant, affecting grain yield; similarly it was believed to be a major source of remobilizing micronutrients (Fe and Zn) for the seeds. At the same time, the seed’s sink strength plays an important role in dry matter accumulation. To investigate the relative contribution of pearl millet flag leaves to protein, micronutrient (Fe and Zn) and phytate accumulation, a field experiment was conducted to evaluate the effect of flag leaf removal on grain test weight (1000 grain weight), protein, micronutrients (Fe and Zn) and Phytate deposition in developing grains of two pearl millet cultivars viz. HC 20 and WHC 901-445. Flag leaf was removed on anthesis. Major effect of flag leaf removal was observed on test weight and protein content. A reduction of 10-12 % in test weight and 4-6 % in protein content was recorded in flag leaf removed plants than that of control plants. No significant reduction was observed in both the micronutrients (Fe and Zn), while phytate content behaved cultivar specific, a significant reduction was observed in HC 20 while it was unaffected in WHC 901-445. Perusal, a significant reduction was observed in all the nutrients in respect of test weight basis. From this investigation it is concluded that flag leaf plays vital role in grain maturation i.e. in supply of carbohydrate and protein fractions while might have limited role in micronutrient remobilization and transportation to developing grains in pearl millet.Not Availabl

Nitrogen metabolism enzymes activity in flag leaf and roots of pearl millet during grain development stage

Nitrate reductase (NR), Glutamine synthatase (GS), Glutamate dehydrogenase (GDH) and Aspartate aminotransaminase (AspAT) were assayed in flag leaves and roots of four pearl millet genotypes, started from ear emergence till grain maturity at four days intervals. All enzymes showed higher activities in flag leaf than that of roots irrespective of growth stage and genotypes. A slight increase in flag leaf NR, GS and AspAT activity till anthesis started decreasing while GDH increased till 12 days after anthesis (DAA) and almost constant till 18 DAA and then started decreasing. While in roots a steep declining trend was observed in NR, GS and AspAT and reached to almost non-detectable level till maturity while GDH increased up to 6 DAA and then decreased sharply irrespective of the genotypes. The almost stable GDH activity and decreasing trend in NR, GS and AspAT suggested that re-assimilation of amino nitrogen takes place in flag leaf instead of direct assimilation from the roots for nitrogen deposition in pearl millet developing grains

Not Available

Not AvailableAntioxidant potential was measured by estimation of total antioxidant activity (TAA) of 92 pearl millet genotypes comprising 46 each of inbreds and designated B-lines (maintainer of CMS lines) grown during kharif-2013 and those of the 27 genotypes (9 inbreds and 18 designated B-lines) selected during kharif-2013 further grown during kharif-2014. TAA was estimated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) method as well as by 2,2'-azino-bis(3-ethylbenzothiazoline -6-sulphonic acid) (ABTS+) method. All the genotypes showed appreciable amount of TAA irrespective of the method used. Average TAA of total genotypes screened during kharif-2013 was 1032 ìg Vit. C equi./g with a wide significant variation from 332 to 1529 µg Vit. C equi./g. The designated B-lines had higher average TAA (1127 µg Vit. C equi./g) than that of inbred lines. During kharif 2014 the average TAA of selected lines varied from 549 to 1880 µg Vit. C equi./g with an average value of 1087 µg Vit. C equi./g (DPPH method) and from 3970 to 6804 µg Trolox equi./g with an average value of 5360 µg Trolox equi./g (ABTS+ method). The average TAA of pearl millet genotypes (DPPH method) was significantly higher than that of commercial samples of wheat (550 µg Vit.C equi./g) and maize (680 µg Vit. C equi./g) procured from local market and tested along with.Not Availabl

Not Available

Not AvailableTo find out the distribution of phytate in pearl millet grain, grains samples of 7 hybrids and 4 composites were decorticated and phytate content of whole grain along with decorticated grain and bran fraction was estimated simultaneously. Bran yield of analyzed hybrids/composites varied from 9.2 to 13.8 %. In decorticated grains (endosperm fraction) phytate content varied from 5.0 mg/g (HC 20) to 6.54 mg/g (HHB 67 improved) with an average value of 5.92 mg/g while in bran fraction it varied from 3.96 mg/g to 4.90 mg/g with an average value of 4.42 mg/g. On an average 5.34 % increment in phytate content was observed on decortications which varied from 3.5 to 9.2 %. A positive correlation was observed between bran content and increase in phytate content in decorticated grains. It is concluded that phytate deposition occurs throughout the endosperm and bran fractions but deposition in endosperm fraction is significantly denser than that in bran fraction. Therefore, decortications might not be the effective process in reduction of phytate content in pearl millet to improve the micronutrient bioavailability.Not Availabl