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51.
The chickpea (Cicer arietinum L.) is a self-pollinated grain legume with cleistogamous flowers. A spontaneous open-flower mutant, designated OFM-3, was identified in which reproductive organs were not enclosed by the keel petals and thus remained exposed. All 10 stamens in this mutant were free, whereas these are in diadelphous (9 fused + 1 free) condition in normal chickpea flowers. A large number of pods (73%) remained unfilled (empty) in OFM-3, though its pollen fertility was as high as the standard cultivars. The open-flower trait was found to be recessive and controlled by a single gene. OFM-3 was crossed with earlier reported open-flower mutants, ICC 16341 and ICC 16129, to establish trait relationships of genes controlling open flower traits in these mutants. It was found that each of these mutants has a unique gene for open flower trait. The genes controlling open flower trait in ICC 16341, ICC 16129, and OFM-3 were designated ofl-1, ofl-2, and ofl-3, respectively. Breeding lines with open flower trait and higher percentage of filled pods have been developed from the progenies of the crosses of OFM-3 with normal-flowered lines. The open flower trait offers opportunity for exploring hybrid technology in the chickpea. 相似文献
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54.
S. P. Tiwari Deepika Yadav Pradeep Kumar D. K. Chauhan 《Plant Systematics and Evolution》2012,298(4):723-730
A comparative study of Taxodium distichum
(L.) Rich. and Taxodium mucronatum
Ten. was carried out on the basis of pollen morphology and wood anatomy by light and scanning electron microscopy. We describe
a detailed analysis of the anatomical characteristics of the wood, including the tracheids, ray parenchyma, axial parenchyma
and number of cross-field pits. Palynological characters were also studied to reveal the shape, size and ultrastructure of
the pollen grains. These studies give taxonomic support for the recognition of T. distichum and T. mucronatum as two different species. 相似文献
55.
Choudhary S Gaur R Gupta S 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(8):1449-1462
Well-saturated linkage maps especially those based on expressed sequence tag (EST)-derived genic molecular markers (GMMs)
are a pre-requisite for molecular breeding. This is especially true in important legumes such as chickpea where few simple
sequence repeats (SSR) and even fewer GMM-based maps have been developed. Therefore, in this study, 2,496 ESTs were generated
from chickpea seeds and utilized for the development of 487 novel EST-derived functional markers which included 125 EST-SSRs,
151 intron targeted primers (ITPs), 109 expressed sequence tag polymorphisms (ESTPs), and 102 single nucleotide polymorphisms
(SNPs). Whereas EST-SSRs, ITPs, and ESTPs were developed by in silico analysis of the developed EST sequences, SNPs were identified
by allele resequencing and their genotyping was performed using the Illumina GoldenGate Assay. Parental polymorphism was analyzed
between C. arietinum ICC4958 and C. reticulatum PI489777, parents of the reference chickpea mapping population, using a total of 872 markers: 487 new gene-based markers
developed in this study along with 385 previously published markers, of which 318 (36.5%) were found to be polymorphic and
were used for genotyping. The genotypic data were integrated with the previously published data of 108 markers and an advanced
linkage map was generated that contained 406 loci distributed on eight linkage groups that spanned 1,497.7 cM. The average
marker density was 3.68 cM and the average number of markers per LG was 50.8. Among the mapped markers, 303 new genomic locations
were defined that included 177 gene-based and 126 gSSRs (genomic SSRs) thereby producing the most advanced gene-rich map of
chickpea solely based on co-dominant markers. 相似文献
56.
Deepika Nehra Hau D. Le Erica M. Fallon Sarah J. Carlson Dori Woods Yvonne A. White Amy H. Pan Lankai Guo Scott J. Rodig Jonathan L. Tilly Bo R. Rueda Mark Puder 《Aging cell》2012,11(6):1046-1054
Women approaching advanced maternal age have extremely poor outcomes with both natural and assisted fertility. Moreover, the incidence of chromosomal abnormalities and birth defects increases with age. As of yet, there is no effective and practical strategy for delaying ovarian aging or improving oocyte quality. We demonstrate that the lifelong consumption of a diet rich in omega‐3 fatty acids prolongs murine reproductive function into advanced maternal age, while a diet rich in omega‐6 fatty acids is associated with very poor reproductive success at advanced maternal age. Furthermore, even short‐term dietary treatment with a diet rich in omega‐3 fatty acids initiated at the time of the normal age‐related rapid decline in murine reproductive function is associated with improved oocyte quality, while short‐term dietary treatment with omega‐6 fatty acids results in very poor oocyte quality. Thus, omega‐3 fatty acids may provide an effective and practical avenue for delaying ovarian aging and improving oocyte quality at advanced maternal age. 相似文献
57.
It is known that folding a protein chain into a cubic lattice is an NP-complete problem. We consider a seemingly easier problem: given a three-dimensional (3D) fold of a protein chain (coordinates of its C(alpha) atoms), we want to find the closest lattice approximation of this fold. This problem has been studied under names such as "lattice approximation of a protein chain", "the protein chain fitting problem", and "building of protein lattice models". We show that this problem is NP-complete for the cubic lattice with side close to 3.8 A and coordinate root mean square deviation. 相似文献
58.
Pushpa Singh Archna Suman Priyanka Tiwari Namita Arya Asha Gaur A. K. Shrivastava 《World journal of microbiology & biotechnology》2008,24(5):667-673
Pretreatment of lignocellulosic biomasses, the first step in their conversion to utilizable molecules requires very high energy
(steam and electricity), corrosion resistant high-pressure reactors and high temperatures. These severe conditions not only
add to the cost component of the entire process but also lead to the loss of sugars to the side reactions. Microbial pretreatments
have been reported to be associated with reducing the cost factors as well as the severities of the reactions. Eight bioagents,
including fungi and bacteria, were screened for their pretreatment effects on sugarcane trash. They narrowed down the C:N
ratio of trash from 108:1 to a varying range of approximately 42:1 to 60:1.The maximum drop in C:N ratio of 61% was observed
using Aspergillus terreus followed by Cellulomonas uda (52%) and Trichoderma reesei and Zymomonas mobilis (49%). The bioagents helped in degradation of sugarcane trash by production of cellulases, the maximum being produced by
A. terreus, (12 fold) followed by C. uda (10 fold), Cellulomonas cartae (9 fold) and Bacillus macerans (8 fold). The microbial pretreatment of trash rendered the easy accessibility of sugars for enzymatic hydrolysis, which can be directed
for production of alcohol. 相似文献
59.
Summary Xylanase from Scytalidium thermophilum was immobilized on Eudragit L-100, a pH sensitive copolymer of methacrylic acid and methyl methacrylate. The enzyme was non-covalently
immobilized and the system expressed 70% xylanase activity. The immobilized preparation had broader optimum temperature of
activity between 55 and 65 °C as compared to 65 °C in case of free enzyme and broader optimum pH between 6.0 and 7.0 as compared
to 6.5 in case of free enzyme. Immobilization increased the t1/2 of enzyme at 60 °C from 15 to 30 min with a stabilization factor of 2. The Km and Vmax values for the immobilized and free xylanase were 0.5% xylan and 0.89 μmol/ml/min and 0.35% xylan and 1.01 μmol/ml/min respectively. An Arrhenius plot showed an increased value of activation energy for immobilized xylanase (227 kcal/mol)
as compared to free xylanase (210 kcal/mol) confirming the higher temperature stability of the free enzyme. Enzymatic saccharification
of xylan was also improved by xylanase immobilization. 相似文献
60.
Pores-Fernando AT Gaur S Grybko MJ Zweifach A 《Biochemical and biophysical research communications》2008,371(4):630-634
Cytotoxic T cells (CTLs) kill target cells by releasing lytic agents via regulated exocytosis. Three signals are known to be required for exocytosis: an increase in intracellular Ca2+, activation of protein kinase C (PKC) and activation of extracellular signal regulated signal kinase (ERK). ERK activation required for exocytosis depends on activity of PKC. The simplest possibility is that the sole effect of PKC required for exocytosis is ERK activation. Testing this requires dissociating ERK and PKC activation. We did this using TCR-independent stimulation of TALL-104 human leukemic CTLs. When cells are stimulated with thapsigargin and PMA, agents that increase intracellular Ca2+ and activate PKC, respectively, PKC-dependent ERK activation is required for lytic granule exocytosis. Expressing a constitutively active mutant MAP kinase kinase activates ERK independent of PKC. However, activating ERK without PKC does not support lytic granule exocytosis, indicating that there are multiple effects of PKC required for granule exocytosis. 相似文献