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121.
Christina Brahe Isabella Velonà Gerrit van der Steege Stefania Zappata Anneke Y. van de Veen Jan Osinga Carli M. J. Tops Riccardo Fodde P. Meera Khan Charles H. C. M. Buys Giovanni Neri 《Human genetics》1994,93(5):494-501
The locus responsible for the childhood-onset proximal spinal muscular atrophies (SMA) has recently been mapped to an area of 2–3 Mb in the region q12–13.3 of chromosome 5. We have used a series of radiation hybrids (RHs) containing distinct parts of the SMA region as defined by reference markers. A cosmid library was constructed from one RH. Thirteen clones were isolated and five of these were mapped within the SMA region. Both RH mapping and fluorescence in situ hybridization analysis showed that two clones map in the region between loci D5S125 and D5S351. One of the cosmids contains expressed sequences. Polymorphic dinucleotide repeats were identified in both clones and used for segregation analysis of key recombinant SMA families. One recombination between the SMA locus and the new marker 9Ic (D5S685) indicates that 9Ic is probably the closest distal marker. The absence of recombination between the SMA locus and marker Fc (D5S684) suggests that Fc is located close to the disease gene. These new loci should refine linkage analysis in SMA family studies and may facilitate the isolation of the disease gene. 相似文献
122.
A simple and efficient method for DNA extraction from grapevine cultivars andVitis species 总被引:3,自引:0,他引:3
Muhammad A. Lodhi Guang-Ning Ye Norman F. Weeden Bruce I. Reisch 《Plant Molecular Biology Reporter》1994,12(1):6-13
A quick, simple, and reliable method for the extraction of DNA from grapevine species, hybrids, andAmpelopsis brevipedunculata (Vitaceae) has been developed. This method, based on that of Doyle and Doyle (1990), is a CTBA-based extraction procedure
modified by the use of NaCl to remove polysaccharides and PVP to eliminate polyphenols during DNA purification. The method
has also been used successfully for extraction of total DNA from other fruit species such as apple (Malus domestica), apricot (Prunus armeniaca), cherry (Prunus avium), peach (Prunus persica), plum (Prunus domestica), and raspberry (Rubus idaeus). DNA yield from this procedure is high (up to 1 mg/g of leaf tissue). DNA is completely digestible with restriction endonucleases
and amplifiable in the polymerase chain reaction (PCR), indicating freedom from common contaminating compounds. 相似文献
123.
Muhammad W. Raza C. Caroline Blackwell Marie M. Ogilvie Abdulrahman T. Saadi John Stewart Robert A. Elton Donald M. Weir 《FEMS immunology and medical microbiology》1994,10(1):25-30
Abstract Viral glycoproteins G and F are expressed on the surface of cells infected with respiratory syncytial virus (RSV). We investigated the role of these proteins in the previously reported enhanced binding of Neisseria meningitidis to RSV-infected HEp-2 cells. Virus particles attached to bacteria were detected by immunofluorescence with flow cytometry. Binding of FITC-labelled bacteria to RSV-infected cells was significantly inhibited by monoclonal antibody against glycoprotein G. Unlabelled bacteria interfered with binding of the anti-G monoclonal antibody to these cells. These interactions were not found with a monoclonal antibody against glycoprotein F. We propose that glycoprotein G of RSV expressed on the surface of infected cells might act as an additional receptor for meningococci. 相似文献
124.
M. Hossain M. R. Karim R. Islam O. I. Joarder 《Plant Cell, Tissue and Organ Culture》1993,34(2):199-203
A protocol for organogenesis from nucellar explants excised from fertilized ovules of immature fruits of Aegle marmelos Corr. was developed. Adventitious buds were initiated on Murashige and Skoog's (MS) medium containing various combinations of 6-benzyladenine (BA), -naphthalene-acetic acid (NAA), 3-indoleacetic acid and gibberellic acid. Medium containing 4.4 m BA and 2.7 M NAA produced the maximum number of adventitious buds per explant. Shoots were elongated by transferring explants with shoot buds to medium with a low concentration of BA (0.44 M). Rooting of in vitro-regenerated shoots was obtained in half-strength MS medium with 4.9 M indole-3-butyric acid. This is the first report of plant regeneration from nucellar explants of A. marmelos.Abbreviations BA
benzyladenine
- IAA
indoleacetic acid
- IBA
indolebutyric acid
- NAA
naphthaleneacetic acid
- GA3
gibberellic acid 相似文献
125.
126.
Citric acid production in surface culture process with reuse of mycelia for more than one batch of media has been reported in this work. A strategy for replacing media and thus increasing productivity in subsequent batches is discussed. An explanation for the decrease in citric acid accumulation beyond the second batch is suggested on the basis of oxygen limitation. 相似文献
127.
S Khan 《Journal of bacteriology》1993,175(8):2169-2174
128.
K. M. Mearow B. G. Thilander I. Khan R. E. Garfield A. K. Grover 《Molecular and cellular biochemistry》1993,121(2):155-165
Heart tissue contains large amounts of the protein encoded by the Ca2+ pump gene SERCA2. The SERCA2 RNA can be spliced alternatively to produce mRNA encoding the proteins SERCA2a and SERCA2b which differ in their C-terminal sequences. In this study we report the tissue distribution of SERCA2a and SERCA2b isoforms byin situ hybridization to rabbit heart and stomach. The expression of SERCA2 mRNA was high in myocardial cells, being the highest in the atrial region. In contrast, there was more SERCA2 protein in Western blots in ventricles than in atria. Myocardial cells expressed predominantly the mRNA for the isoform SERCA2a. Whereas the stomach smooth muscle and the neuronal plexus expressed SERCA2 at levels much lower than myocardial cells, the expression was very high in the stomach mucosa. Mucosa contained mainly the mRNA for SERCA2b. From immunocytochemistry it was concluded that the anti-heart SR Ca2+ pump antibody IID8 reacted much better with heart and surface mucosal cells in the stomach than with the stomach smooth muscle, and that IID8 reactivity was intracellular. In contrast PM4A2B, an antibody against the plasma membrane Ca2+ pump, reacted well with heart and stomach smooth muscle, plexus and mucosa, and its localization appeared to be in the plasma membrane. Thus, stomach smooth muscle expressed SERCA2b mRNA and protein at low levels, mucosa expressed SERCA2b mRNA and protein at high levels, atria and ventricle expressed SERCA2a mRNA and protein at high levels, mRNA being more in atria, but protein being more in ventricles.Deceased August 14, 1992 相似文献
129.
130.
E. J. Breslau-Siderius J. Th. Wijnen J. G. Dauwerse J. M. de Pater F. A. Beemer P. Meera Khan 《Human genetics》1993,92(5):481-485
A de novo duplication of the proximal part of the long arms of chromosome 5 was found in a male born with craniostenosis, ear tags and kidney dysplasia. The nature of the chromosomal aberration was defined by fluorescence in situ hybridization and the orgin of the duplication was traced by polymorphic DNA markers. A comparison is made with the published cases showing similar duplications in the long arm of chromosome 5. 相似文献