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Jagannath A Sodhi YS Gupta V Mukhopadhyay A Arumugam N Singh I Rohatgi S Burma PK Pradhan AK Pental D 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(6):1091-1103
Oil content and oil quality fractions (viz., oleic, linoleic and linolenic acid) are strongly influenced by the erucic acid
pathway in oilseed Brassicas. Low levels of erucic acid in seed oil increases oleic acid content to nutritionally desirable
levels, but also increases the linoleic and linolenic acid fractions and reduces oil content in Indian mustard (Brassica juncea). Analysis of phenotypic variability for oil quality fractions among a high-erucic Indian variety (Varuna), a low-erucic east-European
variety (Heera) and a zero-erucic Indian variety (ZE-Varuna) developed by backcross breeding in this study indicated that
lower levels of linoleic and linolenic acid in Varuna are due to substrate limitation caused by an active erucic acid pathway
and not due to weaker alleles or enzyme limitation. To identify compensatory loci that could be used to increase oil content
and maintain desirable levels of oil quality fractions under zero-erucic conditions, we performed Quantitative Trait Loci
(QTL) mapping for the above traits on two independent F1 doubled haploid (F1DH) mapping populations developed from a cross
between Varuna and Heera. One of the populations comprised plants segregating for erucic acid content (SE) and was used earlier
for construction of a linkage map and QTL mapping of several yield-influencing traits in B. juncea. The second population consisted of zero-erucic acid individuals (ZE) for which, an Amplified Fragment Length Polymorphism
(AFLP)-based framework linkage map was constructed in the present study. By QTL mapping for oil quality fractions and oil
content in the ZE population, we detected novel loci contributing to the above traits. These loci did not co-localize with
mapped locations of the fatty acid desaturase 2 (FAD2),
fatty acid desaturase 3 (FAD3) or fatty acid elongase (FAE) genes unlike those of the SE population wherein major QTL were found to coincide with mapped locations of the FAE genes. Some of the new loci identified in the ZE population could be detected as ‘weak’ contributors (with LOD < 2.5) in
the SE population in which their contribution to the traits was “masked” due to pleiotropic effects of erucic acid genes.
The novel loci identified in this study could now be used to improve oil quality parameters and oil content in B. juncea under zero-erucic conditions. 相似文献
104.
Ramchiary N Padmaja KL Sharma S Gupta V Sodhi YS Mukhopadhyay A Arumugam N Pental D Pradhan AK 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,115(6):807-817
Quantitative trait loci (QTL) analysis of yield influencing traits was carried out in Brassica juncea (AABB) using a doubled haploid (DH) mapping population of 123 lines derived from a cross between Varuna (a line representing
the Indian gene pool) and Heera (representing the east European gene pool) to identify potentially useful alleles from both
the parents. The existing AFLP based map of B. juncea was further saturated with RFLP and SSR markers which led to the identification of the linkage groups belonging to the A
(B. rapa) and B (B. nigra) genome components of B. juncea. For QTL dissection, the DH lines were evaluated at three different environments and phenotyped for 12 quantitative traits.
A total of 65 QTL spread over 13 linkage groups (LG) were identified from the three environments. QTL analysis showed that
the A genome has contributed more than the B genome to productivity (68% of the total QTL detected) suggesting a more prominent
role of the A genome towards domestication of this crop. The east European line, Heera, carried favorable alleles for 42%
of the detected QTL and the remaining 58% were in the Indian gene pool line, Varuna. We observed clustering of major QTL in
a few linkage groups, particularly in J7 and J10 of the A genome, with QTL of different traits having agronomically antagonistic
allelic effects co-mapping to the same genetic interval. QTL analysis also identified some well-separated QTL which could
be readily transferred between the two pools. Based on the QTL analysis, we propose that improvement in yield could be achieved
more readily by heterosis breeding rather than by pure line breeding.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Sehgal PB Mukhopadhyay S 《American journal of physiology. Heart and circulatory physiology》2007,293(1):H77-H85
Histological and electron microscopic studies over the past four decades have highlighted "plump," "enlarged" endothelial, smooth muscle, and fibroblastic cellular elements with increased endoplasmic reticulum, Golgi stacks, and vacuolation in pulmonary arterial lesions in human and in experimental (hypoxia and monocrotaline) pulmonary arterial hypertension. However, the contribution of disrupted intracellular membrane trafficking in the pathobiology of this disease has received insufficient attention. Recent studies suggest a pathogenetic role of the disruption of intracellular trafficking of vasorelevant proteins and cell-surface receptors in the development of this disease. The purpose of this essay is to highlight the molecular regulation of vesicular trafficking by membrane tethers, SNAREs and SNAPs, and to suggest how their dysfunction, directly and/or indirectly, might contribute to development of pulmonary arterial hypertension in experimental models and in humans, including that due to mutations in bone morphogenetic receptor type 2. 相似文献
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Synonymous codon usage and cellular tRNA abundance are thought to be co-evolved in optimizing translational efficiencies in highly expressed genes. Here in this communication by taking the advantage of publicly available gene expression data of rice and Arabidopsis we demonstrated that tRNA gene copy number is not the only driving force favoring translational selection in all highly expressed genes of rice. We found that forces favoring translational selection differ between GC-rich and GC-poor classes of genes. Supporting our results we also showed that, in highly expressed genes of GC-poor class there is a perfect correspondence between majority of preferred codons and tRNA gene copy number that confers translational efficiencies to this group of genes. However, tRNA gene copy number is not fully consistent with models of translational selection in GC-rich group of genes, where constraints on mRNA secondary structure play a role to optimize codon usage in highly expressed genes. 相似文献
110.
Mukhopadhyay BP Ghosh B Bairagya HR Bera AK Roy RK 《Journal of biomolecular structure & dynamics》2007,24(4):369-378
The invariant water molecular interaction involving in the Rusticyanin of Thiobacillus ferrooxidans is thought to be important for its molecular complexation with other proteins at differential acidophilic situation. The comparative analysis of the different x-ray, energy minimized, and auto solvated structures of Rusticyanin revealed the presence of five specific invariant bound water molecules (among the approximately 150 water molecules per monomer) in the crystals. The five W 205, W 206, W 112, W 214, and W 221 water molecules (in Rusticyanin PDB code: 1RCY) were seem to be invariant in all the seven structures (PDB codes: 1RCY, 1A3Z, 1A8Z, 1E3O, 1GY1, 1GY2, 2CAL). Among the five conserved water molecules the W 221 (of 1 RCY or the equivalent water molecules in the other oxidized form of Rusticyanin structures) had endowed an interesting coordination potentiality to Cu(+2) ion during the energy minimization. The W 221 was observed to approach toward the tetrahedrally bonded Cu(+2) ion through the opposite (or trans) route of metal-bonded Met 148. This direct water molecular coordination affected the tetrahedral geometry of Cu(+2) to trigonal bipyramidal. Presumably this structural dynamics at the Cu(+2) center could involve in the electron transport process during protein-protein complexation. 相似文献