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11.
A major difference between the divergence patterns within the lines-1 families in mice and voles 总被引:3,自引:0,他引:3
Vanlerberghe F; Bonhomme F; Hutchison CA d; Edgell MH 《Molecular biology and evolution》1993,10(4):719-731
L1 retroposons are represented in mice by subfamilies of interspersed
sequences of varied abundance. Previous analyses have indicated that
subfamilies are generated by duplicative transposition of a small number of
members of the L1 family, the progeny of which then become a major
component of the murine L1 population, and are not due to any active
processes generating homology within preexisting groups of elements in a
particular species. In mice, more than a third of the L1 elements belong to
a clade that became active approximately 5 Mya and whose elements are >
or = 95% identical. We have collected sequence information from 13 L1
elements isolated from two species of voles (Rodentia: Microtinae: Microtus
and Arvicola) and have found that divergence within the vole L1 population
is quite different from that in mice, in that there is no abundant
subfamily of homologous elements. Individual L1 elements from voles are
very divergent from one another and belong to a clade that began a period
of elevated duplicative transposition approximately 13 Mya. Sequence
analyses of portions of these divergent L1 elements (approximately 250 bp
each) gave no evidence for concerted evolution having acted on the vole L1
elements since the split of the two vole lineages approximately 3.5 Mya;
that is, the observed interspecific divergence (6.7%-24.7%) is not larger
than the intraspecific divergence (7.9%-27.2%), and phylogenetic analyses
showed no clustering into Arvicola and Microtus clades.
相似文献
12.
Bhushan D Pandey A Chattopadhyay A Choudhary MK Chakraborty S Datta A Chakraborty N 《Journal of proteome research》2006,5(7):1711-1720
The extracellular matrix (ECM) or cell wall is a dynamic system and serves as the first line mediator in cell signaling to perceive and transmit extra- and intercellular signals in many pathways. Although ECM is a conserved compartment ubiquitously present throughout evolution, a compositional variation does exist among different organisms. ECM proteins account for 10% of the ECM mass, however, comprise several hundreds of different molecules with diverse functions. To understand the function of ECM proteins, we have developed the cell wall proteome of a crop legume, chickpea (Cicer arietinum). This comprehensive overview of the proteome would provide a basis for future comparative proteomic efforts for this important crop. Proteomic analyses revealed new ECM proteins of unknown functions vis-à-vis the presence of many known cell wall proteins. In addition, we report here evidence for the presence of unexpected proteins with known biochemical activities, which have never been associated with ECM. 相似文献
13.
Baisakh N Rehana S Rai M Oliva N Tan J Mackill DJ Khush GS Datta K Datta SK 《Plant biotechnology journal》2006,4(4):467-475
We have developed near-isogenic introgression lines (NIILs) of an elite indica rice cultivar (IR64) with the genes for β-carotene biosynthesis from dihaploid (DH) derivatives of golden japonica rice (cv. T309). A careful analysis of the DH lines indicated the integration of the genes of interest [phytoene synthase ( psy ) and phytoene desaturase ( crtI )] and the selectable marker gene (hygromycin phosphotransferase, hph ) in two unlinked loci. During subsequent crossing, progenies could be obtained carrying only the locus with psy and crtI , which was segregated independently from the locus containing the hph gene during meiotic segregation. The NIILs (BC2 F2 ) showed maximum similarity with the recurrent parent cultivar IR64. Further, progenies of two NIILs were devoid of any fragments beyond the left or right border, including the chloramphenicol acetyltransferase ( cat ) antibiotic resistance gene of the transformation vector. Spectrophotometric readings showed the accumulation of up to 1.06 µg total carotenoids, including β-carotene, in 1 g of the endosperm. The accumulation of β-carotene was also evident from the clearly visible yellow colour of the polished seeds. 相似文献
14.
Guangxi Wu He Zhao Chenhao Li Menaka Priyadarsani Rajapakse Wing Cheong Wong Jun Xu Charles W. Saunders Nancy L. Reeder Raymond A. Reilman Annika Scheynius Sheng Sun Blake Robert Billmyre Wenjun Li Anna Floyd Averette Piotr Mieczkowski Joseph Heitman Bart Theelen Markus S. Schr?der Paola Florez De Sessions Geraldine Butler Sebastian Maurer-Stroh Teun Boekhout Niranjan Nagarajan Thomas L. Dawson Jr. 《PLoS genetics》2015,11(11)
Malassezia is a unique lipophilic genus in class Malasseziomycetes in Ustilaginomycotina, (Basidiomycota, fungi) that otherwise consists almost exclusively of plant pathogens. Malassezia are typically isolated from warm-blooded animals, are dominant members of the human skin mycobiome and are associated with common skin disorders. To characterize the genetic basis of the unique phenotypes of Malassezia spp., we sequenced the genomes of all 14 accepted species and used comparative genomics against a broad panel of fungal genomes to comprehensively identify distinct features that define the Malassezia gene repertoire: gene gain and loss; selection signatures; and lineage-specific gene family expansions. Our analysis revealed key gene gain events (64) with a single gene conserved across all Malassezia but absent in all other sequenced Basidiomycota. These likely horizontally transferred genes provide intriguing gain-of-function events and prime candidates to explain the emergence of Malassezia. A larger set of genes (741) were lost, with enrichment for glycosyl hydrolases and carbohydrate metabolism, concordant with adaptation to skin’s carbohydrate-deficient environment. Gene family analysis revealed extensive turnover and underlined the importance of secretory lipases, phospholipases, aspartyl proteases, and other peptidases. Combining genomic analysis with a re-evaluation of culture characteristics, we establish the likely lipid-dependence of all Malassezia. Our phylogenetic analysis sheds new light on the relationship between Malassezia and other members of Ustilaginomycotina, as well as phylogenetic lineages within the genus. Overall, our study provides a unique genomic resource for understanding Malassezia niche-specificity and potential virulence, as well as their abundance and distribution in the environment and on human skin. 相似文献
15.
16.
Hardies SC; Martin SL; Voliva CF; Hutchison CA d; Edgell MH 《Molecular biology and evolution》1986,3(2):109-125
17.
Narayanan Narayanan N. Baisakh Niranjan Oliva Norman P. VeraCruz Casiana M. Gnanamanickam Samuel S. Datta Karabi Datta Swapan K. 《Molecular breeding : new strategies in plant improvement》2004,14(1):61-71
Based on blast pathogen population dynamics and lineage exclusion assays, we found that the major blast resistance genes Pi-1 and Piz-5 confer resistance against most Magnaporthe grisea lineages. Near-isogenic rice lines C101LAC and C101A51 carrying these two major genes for blast resistance in the background of a most blast-susceptible genotype were used for developing the pyramids. The closely linked RFLP marker RZ536 and NBS-LRR r10 marker for Pi-1 and a PCR-based SAP marker RG64 for Piz-5 were used to identify the genes in the parents and in marker-assisted breeding of the pyramided populations. To achieve multiple resistance against blast and blight in this cultivar, these blast-resistant pyramids were transformed with the cloned bacterial blight resistance gene Xa21 known to confer resistance to all races of Xanthomonas oryzae pv. oryzae (Xoo). Bioassays with six independent transformants showed that transgenic CO39 plants were resistant to both pathogens, M. grisea and Xoo. We report here the stacking of three major genes (Pi-1 + Piz-5 + Xa21) into rice using two different approaches of molecular breeding: marker-assisted selection (MAS) and genetic transformation. 相似文献
18.
Experimental evidences have confirmed that matrix metalloproteinases (MMPs) play a fundamental role in a wide variety of pathologic conditions and recent advances in medicinal chemistry approach to the design of MMP inhibitors with desired structural and functional properties. Among MMPs, MMP-9 has demonstrated to play a major role in the establishment of metastases and it is substantially increased in the majority of malignant tumors. Inhibition of MMP-9 is thought to have a therapeutic benefit to cancer. Results of this study present a novel synthetic MMP-9 inhibitor that downregulates MMP-9 expression level in HT1080, human fibrosarcoma cells. 相似文献
19.
Kim MM Ta QV Mendis E Rajapakse N Jung WK Byun HG Jeon YJ Kim SK 《Life sciences》2006,79(15):1436-1443
Matrix metalloproteinase (MMP) inhibitors have been identified as potential therapeutic candidates for metastasis, arthritis, chronic inflammation and wrinkle formation. For the first time here we report a detailed study on the inhibitory effects of phlorotannins in brown algae, Ecklonia cava (EC) on MMP activities in cultured human cell lines. A novel gelatin digestion assay could visualize complete inhibition of bacterial collagenase-1 activity at 20 microg/ml of EC extract during preliminary screening studies. Sensitive fluorometric assay revealed that EC extract can specifically inhibit both MMP-2 and MMP-9 activities significantly (P < 0.001) at 10 microg/ml. In addition, artificially induced activities of MMP-2 and MMP-9 in human dermal fibroblasts and HT1080 cells were inhibited by EC extract in a more or less similar manner to the positive control doxycycline. Even though the expression levels of MMPs differ from one cell type to the other, gelatin zymography clearly revealed that both MMP expression and activity in cells can be inhibited by EC extract. More interestingly, EC extract did not exert any cytotoxic effect even at 100 microg/ml anticipating its potential use as a safe MMP inhibitor. 相似文献
20.
Renu Deswal Ravi Gupta Vivek Dogra Raksha Singh Jasmeet Kaur Abat Abhijit Sarkar Yogesh Mishra Vandana Rai Yelam Sreenivasulu Ramesh Sundar Amalraj Manish Raorane Ram Prasad Chaudhary Ajay Kohli Ashok Prabhakar Giri Niranjan Chakraborty Sajad Majeed Zargar Vishwanath Prasad Agrawal Ganesh Kumar Agrawal Dominique Job Jenny Renaut Randeep Rakwal 《Physiology and Molecular Biology of Plants》2013,19(4):461-477
Plant proteomics has made tremendous contributions in understanding the complex processes of plant biology. Here, its current status in India and Nepal is discussed. Gel-based proteomics is predominantly utilized on crops and non-crops to analyze majorly abiotic (49 %) and biotic (18 %) stress, development (11 %) and post-translational modifications (7 %). Rice is the most explored system (36 %) with major focus on abiotic mainly dehydration (36 %) stress. In spite of expensive proteomics setup and scarcity of trained workforce, output in form of publications is encouraging. To boost plant proteomics in India and Nepal, researchers have discussed ground level issues among themselves and with the International Plant Proteomics Organization (INPPO) to act in priority on concerns like food security. Active collaboration may help in translating this knowledge to fruitful applications. 相似文献