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71.
Dawn L. Thiselton Christiane Alexander Alex Morris Simon Brooks Thomas Rosenberg Hans Eiberg Birgit Kjer Poul Kjer Shomi S. Bhattacharya Marcela Votruba 《Human genetics》2001,109(5):498-502
Dominant optic atrophy (DOA) is a hereditary optic neuropathy characterised by decreased visual acuity, colour vision deficits, centro-coecal scotoma and optic nerve pallor. The gene OPA1, encoding a dynamin-related GTPase, has recently been identified within the genetic linkage interval for the major locus for DOA on chromosome 3q28 and shown to harbour genetic aberrations segregating with disease in DOA families. The prevalence of the disorder in Denmark is reported to be the highest of any geographical location, suggestive of a founder effect. In order to establish the genetic basis of disease in a sample of 33 apparently unrelated Danish families, we screened DNA from affected members for OPA1 gene mutations by heteroduplex analysis and direct sequencing. A novel identical mutation in exon 28 (2826delT) was associated with DOA in 14 pedigrees and led to a frameshift and abnormal OPA1 protein -COOH terminus. Haplotype analysis of a region of approximately 1 Mb flanking the OPA1 gene using eight polymorphic markers revealed a common haplotype shared by all 14 patients; this haplotype was markedly over-represented compared with ethnically matched controls. Statistical analysis confirmed significant linkage disequilibrium with DOA over approximately 600 kb encompassing the disease mutation. We have therefore demonstrated that the relatively high frequency of DOA in Denmark is attributable to a founder mutation responsible for approximately 42% of the examined families and suggest that presymptomatic screening for the (2826delT) mutation may facilitate diagnosis and genetic counselling in a significant proportion of DOA patients of Danish ancestry. 相似文献
72.
Epigenetic mechanisms of plant stress responses and adaptation 总被引:3,自引:0,他引:3
Pranav Pankaj Sahu Garima Pandey Namisha Sharma Swati Puranik Mehanathan Muthamilarasan Manoj Prasad 《Plant cell reports》2013,32(8):1151-1159
Epigenetics has become one of the hottest topics of research in plant functional genomics since it appears promising in deciphering and imparting stress-adaptive potential in crops and other plant species. Recently, numerous studies have provided new insights into the epigenetic control of stress adaptation. Epigenetic control of stress-induced phenotypic response of plants involves gene regulation. Growing evidence suggest that methylation of DNA in response to stress leads to the variation in phenotype. Transposon mobility, siRNA-mediated methylation and host methyltransferase activation have been implicated in this process. This review presents the current status of epigenetics of plant stress responses with a view to use this knowledge towards engineering plants for stress tolerance. 相似文献
73.
A ubiquitous beta-tubulin disrupts microtubule assembly and inhibits cell proliferation 总被引:10,自引:0,他引:10
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Vertebrate tubulin is encoded by a multigene family that produces distinct gene products, or isotypes, of both the alpha- and beta-tubulin subunits. The isotype sequences are conserved across species supporting the hypothesis that different isotypes subserve different functions. To date, however, most studies have demonstrated that tubulin isotypes are freely interchangeable and coassemble into all classes of microtubules. We now report that, in contrast to other isotypes, overexpression of a mouse class V beta-tubulin cDNA in mammalian cells produces a strong, dose-dependent disruption of microtubule organization, increased microtubule fragmentation, and a concomitant reduction in cellular microtubule polymer levels. These changes also disrupt mitotic spindle assembly and block cell proliferation. Consistent with diminished microtubule assembly, there is an increased tolerance for the microtubule stabilizing drug, paclitaxel, which is able to reverse many of the effects of class V beta-tubulin overexpression. Moreover, transfected cells selected in paclitaxel exhibit increased expression of class V beta-tubulin, indicating that this isotype is responsible for the drug resistance. The results show that class V beta-tubulin is functionally distinct from other tubulin isotypes and imparts unique properties on the microtubules into which it incorporates. 相似文献
74.
Payal Singh Pradipta Bandyopadhyay Sudha Bhattacharya A Krishnamachari Supratim Sengupta 《BMC bioinformatics》2009,10(1):325
Background
Riboswitches are a type of noncoding RNA that regulate gene expression by switching from one structural conformation to another on ligand binding. The various classes of riboswitches discovered so far are differentiated by the ligand, which on binding induces a conformational switch. Every class of riboswitch is characterized by an aptamer domain, which provides the site for ligand binding, and an expression platform that undergoes conformational change on ligand binding. The sequence and structure of the aptamer domain is highly conserved in riboswitches belonging to the same class. We propose a method for fast and accurate identification of riboswitches using profile Hidden Markov Models (pHMM). Our method exploits the high degree of sequence conservation that characterizes the aptamer domain. 相似文献75.
76.
77.
Deep S. Chini Manojit Bhattacharya Avijit Kar Ramesh C. Malick Bidhan C. Patra Shampa Patra Basanta K. Das 《Zeitschrift fur angewandte Ichthyologie》2019,35(2):585-586
The length–weight relationships (LWRs) of three freshwater fish species from the Kangsabati and Rupnaryan river in West Bengal, India are presented, namely as Amblypharyngodon microlepis (Bleeker, 1853), Parambassis lala (Hamilton, 1822) and Macrognathus aculeatus (Bloch, 1786). Gill‐nets (mesh sizes with 0.5 cm–4 cm), cast‐nets (up to 1 × 1 cm mesh size with up to 4.0 m2 area) and scoop‐nets (0.3 × 0.3 cm and 0.5 × 0.5 cm mesh size) were used from January, 2017 to April, 2018. Sampling was done every 15 days during this period. The value of parameter “b” ranged from 2.751 to 2.895 with highly significant correlations (r2 > 0.95). 相似文献
78.
A strain ofLactobacillus acidophilus (Strain HF) was isolated from human faeces. A chloramphenicol resistant strain (HFCm) and a strain (HFCmSm) restant to both
chloramphenicol and streptomycin were developed from the isolated strain (HF). All the three strains showed similarin vitro susceptibility against host defence factors like gastric acid, bile salts and volatile as well as non-volatile fatty acids.In vivo tests were done by feeding these strains to mice. When the resistant strains were orally administered along with the antibiotic(s)
they were stable up to 72 h 相似文献
79.
Amita?Bhattacharya P.?K.?NagarEmail author Paramvir?Singh?Ahuja 《Acta Physiologiae Plantarum》2004,26(4):399-404
The role of endogenous indole-3-acetic acid (IAA), soluble proteins and RNA in the development of tea (Camellia sinensis (L). O. Kuntze) seeds was investigated in the present study. The state of continuum even at full maturity and lack of a clear
end point to seed development as indicated by the persistence of appreciable contents of proteins at full maturity in all
the seed parts further confirmed the ‘recalcitrant nature’ of the tea seeds. Unlike the orthodox seeds, the level of free
IAA in tea embryos also remained high even at full maturity. The total RNA content remained high in the stages with high moisture
content but declined with progressive decline in moisture content. 相似文献
80.