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51.
52.
L. Rajendran G. A. Ravishankar L. V. Venkataraman K. R. Prathiba 《Biotechnology letters》1992,14(8):707-712
Summary
Daucus
carota callus developed red pigments under the influence of indole-3 acetic acid and kinetin. Maximum yield of anthocyanin at the end of 3 weeks was 5.4% on dry weight basis. The callus subjected to phosphate and nitrate stress produced 7.2% and 8.5% anthocyanin respectively. Feeding of sucrose at 7.5% level resulted in production of 15% anthocyanin. Mannitol as osmoticum had positive influence on anthocyanin production. 相似文献
53.
T. Sudhakar Johnson G. A. Ravishankar L. V. Venkataraman 《Plant Cell, Tissue and Organ Culture》1996,46(2):117-121
Plant tissue culture medium which contained FeEDTA as sole iron source was incubated aseptically in light (16-h photoperiod, 100 mol m-2 s-1 PAR) at 20°C without plant tissue. Soluble iron dropped from an initial concentration of 4 mg 1-1 to less than 0.1 mg 1-1 in 4 weeks. This occurred in both glass and plastic culture vessels. No loss occurred when medium was incubated at 20°C in darkness. A further experiment showed that soluble iron concentration fell to <0.2 mg 1-1 in only 4 days but the loss was slower at lower irradiances.Effects of the loss of soluble iron on plantlet growth were assessed by culturing single node stem segments of in vitro potato (Solanum tuberosum L. cv. Arran Banner) plantlets on medium previously exposed to light. Pre-exposure sufficient to reduce soluble iron concentration to <0.1 mg 1-1 had no inhibitory effect on plantlet development in solidified medium or in liquid medium, except when the liquid medium had been centrifuged before inoculation to remove iron precipitated during pre-exposure to light. The plantlets then became chlorotic. 相似文献
54.
Ravishankar R. Patil Kiran D. Pawar Manali R. Rane Shrirang R. Yadav Vishwas A. Bapat Jyoti P. Jadhav 《Physiology and Molecular Biology of Plants》2016,22(2):207-217
Genus Mucuna which is native to China and Eastern India comprises of perennial climbing legume with long slender branches, trifoliate leaves and bear green or brown pod covered with soft or rigid hairs that cause intense irritation. The plants of this genus are agronomically and economically important and commercially cultivated in India, China and other regions of the world. The high degrees of taxonomical confusions exist in Mucuna species that make authentic identification and classification difficult. In the present study, the genetic diversity among the 59 accessions of six species and three varieties of M. pruriens has been assessed using DNA fingerprinting based molecular markers techniques namely randomly amplified polymorphic DNA (RAPD), inter simple sequence repeats (ISSR) and combined dataset of RAPD and ISSR. Also, genetic relationship among two endemic species of Mucuna namely M. imbricata and M. macrocarpa and two varieties namely IIHR hybrid (MHR) and Dhanwantari (MD) with other species under study was investigated by using cluster analysis and principal coordinate analysis. The cluster analysis of RAPD, ISSR and combined dataset of RAPD and ISSR clearly demonstrated the existence of high interspecific variation than intra-specific variation in genus Mucuna. The utility and efficacy of RAPD and ISSR for the study of intra species and interspecies genetic diversity was evident from AMOVA and PCoA analysis. This study demonstrates the genetic diversity in Mucuna species and indicates that these markers could be successfully used to assess genetic variation among the accessions of Mucuna species. 相似文献
55.
Isolation of a cytochrome P-450e gene variant and characterization of its 5' flanking sequences 总被引:1,自引:0,他引:1
P N Rangarajan H Ravishankar G Padmanaban 《Biochemical and biophysical research communications》1987,144(1):258-263
A cytochrome P-450e gene variant has been isolated from the rat liver genomic library. It is a typical e gene clone but unique in having b-like single base substitutions at specific sites in the 5' flanking region. It also appears to have certain additional restriction sites in the introns. When compared with the cytochrome P-450b gene, the e gene has some of the repetitive motifs interrupted in the 5' flanking region. In addition, this region is characterized by the presence of alternating pyrimidine-purine stretch, steroid hormone regulatory elements, consensus eukaryotic enhancer sequence and sequences involved in general amino acid regulation. 相似文献
56.
Balawant Kumar Chakrapani Tripathi Ranjana K. Kanchan Jitendra Kumar Tripathi Jimut K. Ghosh Ravishankar Ramachandran Smrati Bhadauria Raj Kamal Tripathi 《PloS one》2013,8(6)
FasL mediated preferential apoptosis of bystander CTLs while protection of infected CD4+T cells remains one of the hallmarks of immune evasion during HIV infection. The property of infected host cells to evade cell-autonomous apoptosis emanates from ability of HIV-1Nef -protein to physically interact with ASK-1 and thereby inhibit its enzymatic activity. The specific domains of HIV-1Nef through which it may interact with ASK1 and thereby impair the ASK1 activity remain unidentified so far and represent a major challenge towards developing clear understanding about the dynamics of this interaction. Using mammalian two hybrid screen in association with site directed mutagenesis and competitive inhibitor peptides, we identified constituent minimal essential domain (152 DEVGEANN 159) through which HIV-1Nef interacts with ASK1 and inhibits its function. Furthermore our study also unravels a novel alternate mechanism underlying HIV-1 Nef mediated ASK1 functional modulation, wherein by potentiating the inhibitory ser967 phosphorylation of ASK1, HIV-1Nef negatively modulated ASK1function. 相似文献
57.
Zachary D. Stephens Skylar Y. Lee Faraz Faghri Roy H. Campbell Chengxiang Zhai Miles J. Efron Ravishankar Iyer Michael C. Schatz Saurabh Sinha Gene E. Robinson 《PLoS biology》2015,13(7)
Genomics is a Big Data science and is going to get much bigger, very soon, but it is not known whether the needs of genomics will exceed other Big Data domains. Projecting to the year 2025, we compared genomics with three other major generators of Big Data: astronomy, YouTube, and Twitter. Our estimates show that genomics is a “four-headed beast”—it is either on par with or the most demanding of the domains analyzed here in terms of data acquisition, storage, distribution, and analysis. We discuss aspects of new technologies that will need to be developed to rise up and meet the computational challenges that genomics poses for the near future. Now is the time for concerted, community-wide planning for the “genomical” challenges of the next decade.We compared genomics with three other major generators of Big Data: astronomy, YouTube, and Twitter. Astronomy has faced the challenges of Big Data for over 20 years and continues with ever-more ambitious studies of the universe. YouTube burst on the scene in 2005 and has sparked extraordinary worldwide interest in creating and sharing huge numbers of videos. Twitter, created in 2006, has become the poster child of the burgeoning movement in computational social science [6], with unprecedented opportunities for new insights by mining the enormous and ever-growing amount of textual data [7]. Particle physics also produces massive quantities of raw data, although the footprint is surprisingly limited since the vast majority of data are discarded soon after acquisition using the processing power that is coupled to the sensors [8]. Consequently, we do not include the domain in full detail here, although that model of rapid filtering and analysis will surely play an increasingly important role in genomics as the field matures.To compare these four disparate domains, we considered the four components that comprise the “life cycle” of a dataset: acquisition, storage, distribution, and analysis (
Data Phase
Astronomy
Twitter
YouTube
Genomics
Acquisition
25 zetta-bytes/year 0.5–15 billion tweets/year 500–900 million hours/year 1 zetta-bases/year
Storage
1 EB/year 1–17 PB/year 1–2 EB/year 2–40 EB/year
Analysis
In situ data reduction Topic and sentiment mining Limited requirements Heterogeneous data and analysis Real-time processing Metadata analysis Variant calling, ~2 trillion central processing unit (CPU) hours Massive volumes All-pairs genome alignments, ~10,000 trillion CPU hours
Distribution
Dedicated lines from antennae to server (600 TB/s) Small units of distribution Major component of modern user’s bandwidth (10 MB/s) Many small (10 MB/s) and fewer massive (10 TB/s) data movement