68 research outputs found
Four genes encoding MYB28, a major transcriptional regulator of the aliphatic glucosinolate pathway, are differentially expressed in the allopolypoloid Brassica juncea
Glucosinolates are Capparales-specific secondary metabolites that have immense potential in human health and agriculture. Unlike Arabidopsis thaliana, our knowledge about glucosinolate regulators in the Brassica crops is sparse. In the current study, four MYB28 homologues were identified (BjuMYB28-1,-2,-3,-4) from the polyploid Brassica juncea, and the effects of allopolyploidization on the divergence of gene sequence, structure, function, and expression were assessed. The deduced protein sequences of the four BjuMYB28 genes showed 76.1–83.1% identity with the Arabidopsis MYB28. Phylogenetic analysis revealed that the four BjuMYB28 proteins have evolved via the hybridization and duplication processes forming the B. juncea genome (AABB) from B. rapa (AA) and B. nigra (BB), while retaining high levels of sequence conservation. Mutant complementation and over-expression studies in A. thaliana showed that all four BjuMYB28 genes encode functional MYB28 proteins and resulted in similar aliphatic glucosinolate composition and content. Detailed expression analysis using qRT-PCR assays and promoter-GUS lines revealed that the BjuMYB28 genes have both tissue- and cell-specific expression partitioning in B. juncea. The two B-genome origin BjuMYB28 genes had more abundant transcripts during the early stages of plant development than the A-genome origin genes. However, with the onset of the reproductive phase, expression levels of all four BjuMYB28 increased significantly, which may be necessary for producing and maintaining high amounts of aliphatic glucosinolates during the later stages of plant development. Taken together, our results suggest that the four MYB28 genes are differentially expressed and regulated in B. juncea to play discrete though overlapping roles in controlling aliphatic glucosinolate biosynthesis
Synthesis of plant growth regulator analogues from aleuritic acid
Plant growth regulators (PGR’S) having either stimulating or retarding activity are
non-pollutive and cost-effective compounds to bring about changes of desired productivity in
agricultural crops. Among these compounds one group comprises of the aliphatic nature with remarkable and definite activity in the physiology of plant growth. This paper covers syntheses of two unreported PGR analogues (VIII) and (V) from threo-aleuritic acid“, 9, 10
16-trihydroxyhexadecanoic acid (I), the major constituent acid of lac, believed to be present
to the extent of 35%
A Mild and Efficient Method for the Syntheses and Regioselective Ring-Opening of Aziridines
We have developed a new synthetic method for the synthesis of aziridines using Chloramine-T as an effective reagent in the presence of NH2OH center dot HCl and NaIO4. We found that the same combination of NH2OH center dot HCl and NaIO4 is also very effective for nucleophilic ring opening of aziridines.This research was funded by the Russian Science Foundation, grant number 18-19-00090
A Mild and Efficient Method for the Syntheses and Regioselective Ring-Opening of Aziridines
We have developed a new synthetic method for the synthesis of aziridines using Chloramine-T as an effective reagent in the presence of NH 2OH·HCl and NaIO 4. We found that the same combination of NH 2OH·HCl and NaIO 4is also very effective for nucleophilic ring opening of aziridines. Copyright © 2017 Georg Thieme Verlag Stuttgart · New York
Combination of NH2OHHCl and NaIO4: A new and mild reagent for the synthesis of vicinal diiodo carbonyl compounds
The synthesis of vicinal diiodo carbonyl compounds from α,β-unsaturated carbonyl compounds has been carried out for the first time using the combination of NH2OHHCl and NaIO4 under mild reaction conditions at room temperature. The present methodology is also applicable for the synthesis of vicinal diiodo derivatives of nitrostyrene. The remarkable advantages of the present protocol are room temperature reaction, easy operation, good yields, fast reaction, transition metal-free and neutral reaction conditions. The present methodology is applicable to gram scale synthesis. © 2016 Arkat. All rights reserved
LHC and lepton flavour violation phenomenology of a left-right extension of the MSSM
We study the phenomenology of a supersymmetric left-right model, assuming
minimal supergravity boundary conditions. Both left-right and (B-L) symmetries
are broken at an energy scale close to, but significantly below the GUT scale.
Neutrino data is explained via a seesaw mechanism. We calculate the RGEs for
superpotential and soft parameters complete at 2-loop order. At low energies
lepton flavour violation (LFV) and small, but potentially measurable mass
splittings in the charged scalar lepton sector appear, due to the RGE running.
Different from the supersymmetric 'pure seesaw' models, both, LFV and slepton
mass splittings, occur not only in the left- but also in the right slepton
sector. Especially, ratios of LFV slepton decays, such as Br()/Br() are sensitive to the
ratio of (B-L) and left-right symmetry breaking scales. Also the model predicts
a polarization asymmetry of the outgoing positrons in the decay , A ~ [0,1], which differs from the pure seesaw 'prediction' A=1$.
Observation of any of these signals allows to distinguish this model from any
of the three standard, pure (mSugra) seesaw setups.Comment: 43 pages, 17 figure
Right-handed Sneutrino Dark Matter in Supersymmetric B-L Model
We show that the lightest right-handed sneutrino in TeV scale supersymmetric
B-L model with inverse seesaw mechanism is a viable candidate for cold dark
matter. We find that it accounts for the observed dark matter relic abundance
in a wide range of parameter space. The spin-independent cross section of B-L
right-handed sneutrino is consistent with the recent results CDMS II and XENON
experiments and it is detectable in future direct detection experiments.
Although the B-L right-handed sneutrinos annihilate into leptons, the PAMELA
results can not be explained in this model unless a huge boost factor is
considered. Also the muon flux generated by B-L right-handed sneutrino in the
galactic center is smaller than Super-Kamiokande's upper bound.Comment: 16 pages, 7 figures; version accepted for publication in Journal of
High Energy Physic
Implications of Recent Data on Neutrino Mixing and Lepton Flavour Violating Decays for the Zee Model
We study implications of recent data on neutrino mixing from T2K, MINOS,
Double Chooz and from MEG for the Zee model. The simplest
version of this model has been shown to be ruled out by experimental data some
time ago. The general Zee model is still consistent with recent data. We
demonstrate this with a constrained Zee model based on naturalness
consideration. In this constrained model, only inverted mass hierarchy for
neutrino masses is allowed, and must be non-zero in order to have
correct ratio for neutrino mass-squared differences and for mixing in solar and
atmospherical neutrino oscillations. The best fit value of our model for
is from T2K and MINOS data, very close to the central
value obtained by Double Chooz experiment. There are solutions with non-zero CP
violation with the Jarlskog parameter predicted in the range , and respectively for a 1, 2 and 3
ranges of other input parameters. However, without any constraint on the
-parameter above respective ranges become ,
and . We analyse different cases to obtain a branching ratio for
close to the recent MEG bound. We also discuss other
radiative as well as the charged trilepton flavour violating decay modes of the
-lepton.Comment: References added, one extra figure added, typos corrected, few more
related phenomenology discussion added/modified; 25 pages, 10 figure
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