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61.
Antibody was raised against a synthetic undecapeptide (PS 11) which corresponds to the prosegment of the rat tissue kallikrein precursor. The potential to recognize rat urinary active or inactive kallikrein was assessed by an enzyme immunoassay method for PS 11, using beta-D-galactosidase as the labeling enzyme. The active kallikrein failed to compete with the enzyme-labeled PS 11 in binding to the antibody. The inactive kallikrein displaced the enzyme-labeled PS 11 in this enzyme immunoassay, and the displacement curve was in parallel with that of PS 11. These results indicate that rat urinary inactive kallikrein contains a prosequence recognized by the antibody to PS 11. This inactive kallikrein is probably a proform of tissue kallikrein. 相似文献
62.
K Fujimori K E Rodgers R M Nakamura E Katt D L Yanagihara G S diZerega 《The journal of histochemistry and cytochemistry》1988,36(6):589-595
The granulosa cell secretes a protein (follicle regulatory protein: FRP) that affects the responsiveness of other follicles to gonadotropin stimulation. This protein was purified, partially characterized, and rabbit antisera as well as monoclonal antibodies were prepared against FRP. Fixed sections of porcine ovaries were prepared on slides and then incubated with the monoclonal antibody or polyclonal antisera and then incubated with either biotinylated mouse IgM or rabbit IgG antisera, respectively. These sections were then incubated with avidin conjugated to horseradish peroxidase, followed by substrate. Staining with both the monoclonal antibody and the antisera was present in the cytoplasm of granulosa cells of small- or medium-sized antral follicles. Staining distribution was localized preferentially to cells near the basal lamina; the antral granulosa cells of viable follicles did not stain. Neither primordial follicles nor pre-antral follicles (less than 300 microns in diameter) showed any positive staining. Thecal cells were not stained in follicles less than 5 mm in diameter, whereas some large follicles (greater than 5 mm) contained staining in the theca. In the latter, specific granulosa staining was only weakly positive with the polyclonal antibody and negative with the monoclonal antibody. Atretic follicles contained significant staining of all epithelial cells adjacent to the basal lamina by both the monoclonal and polyclonal antibody preparations. Staining of the luteal ovary by the monoclonal antibody was limited to the large luteal cells. These findings suggest that FRP is produced by the granulosa cells of porcine follicles at the stage of maturation corresponding to 0.5 mm in diameter. As the viable follicle increases in size, production of FRP in the granulosa is reduced below the detectable level when the follicle exceeds 5 mm in diameter. The main source of FRP during the luteal phase is the large cell of the corpus luteum. 相似文献
63.
Peter O''Connell G. Mark Lathrop Mark Leppert Yusuke Nakamura Ulrich Müller Jean-Marc Lalouel Ray White 《Genomics》1988,3(4):367-372
We have constructed a primary genetic map of human chromosome 18 consisting of 11 DNA markers and one serological marker (JK). Two of these loci define highly polymorphic VNTR systems. The markers define a continuous genetic linkage map of 97 cM in males and 205 cM in females; female genetic distances in a panel of 59 three-generation families were consistently about twice those observed in males. The high odds in support of the linear order of the markers on this recombination map, and the extent of coverage of chromosome 18, indicate that this map will permit efficient linkage studies of human genetic diseases that may be segregating on chromosome 18 and will provide anchor points for development of high-resolution maps for this chromosome. 相似文献
64.
65.
66.
Tomohiko Suzuki Akio Nakamura Yoshiaki Satoh Chisato Inai Takahiro Furukohri Tomikazu Arita 《Journal of Protein Chemistry》1992,11(6):629-633
The blood clamBarbatia virescens has a heterodimeric hemoglobin in erythrocytes. Interestingly, the congeneric clamsB. reeveana andB. lima contain quite different hemoglobins: tetramer and polymeric hemoglobin consisting of unusual didomain chain. The complete amino acid sequence of chain I ofB. virescens has been determined. The sequence was mainly determined from CNBr peptides and their subpeptides, and the alignment of the peptides was confirmed by sequencing of PCR-amplified cDNA forB. virescens chain I. The cDNA-derived amino acid sequence matched completely with the sequence proposed from protein sequencing.B. virescens chain I is composed of 156 amino acid residues, and the molecular mass was calculated to be 18,387 D, including a heme group. The sequence ofB. virescens chain I showed 35–42% sequence identity with those of the related clamAnadara trapezia and the congeneric clamB. reeveana. An evolutionary tree forAnadara andBarbatia chains clearly indicates that all of the chains are evolved from one ancestral globin gene, and that the divergence of chains has occurred in each clam after the speciation. The evolutionary rate for clam hemoglobins was estimated to be about four times faster than that of vertebrate hemoglobin. We suggest that blood clam hemoglobin is a physiologically less important molecule when compared with vertebrate hemoglobins, and so it evolved rapidly and resulted in a remarkable diversity in quaternary and subunit structure within a relatively short period. 相似文献
67.
Sylviane Olschwang Richard Fabre Pierre Laurent-Puig Anne Vassal Bernard Hamelin Yusuke Nakamura Gilles Thomas 《Human genetics》1992,88(6):658-660
Summary The EF5.44 locus is in close proximity to the chromosome 5 region to which the genetic defect responsible for familial adenomatous polyposis has been mapped. We have devised two oligonucleotides that promote the specific polymerase chain reaction (PCR) amplificiation of a 365-bp sequence in this region. Analysis by denaturing gradient gel electrophoresis of the resulting fragment has unravelled individual differences that could be identified as a single base pair change in aMnlI restriction site. This PCR assayable polymorphism increases the informativeness at this locus, and should be useful in the presymptomatic diagnosis of familial adenomatous polyposis. 相似文献
68.
Complete nucleotide sequence of the mitochondrial DNA from a liverwort,Marchantia polymorpha 总被引:1,自引:1,他引:0
Kenji Oda Katsuyuki Yamato Eiji Ohta Yasukazu Nakamura Miho Takemura Naoko Nozato Kinya Akashi Takeshi Kanegae Yutaka Ogura Takayuki Kohchi Kanji Ohyama 《Plant Molecular Biology Reporter》1992,10(2):105-163
Libraries of cosmid and plasmid clones covering the entire region of mtDNA from the liverwortMarchantia polymorpha were constructed. These clones were used for the determination of the complete nucleotide sequence of the liverwort mtDNA
totally 186,608 bp (GenBank no. M68929) and including genes for 3 species of ribosomal RNAs, 29 genes for 27 species of transfer
RNAs, and 30 genes for functionally known proteins (16 ribosomal proteins, 3 subunits of cytochromec oxidase, apocytochromeb protein, 3 subunits of H+-ATPase, and 7 subunits of NADH ubiquinone oxidoreductase). The genome also contains 32 unidentified open reading frames.
Thus the complete nucleotide sequences from both chloroplast and mitochondrial genomes have been determined in the same organism.
Plasmid clones are available upon the request.
Gene names are represented according to Lonsdale and Leaver (1988) with modifications recommended by Lonsdale (personal communication). 相似文献
69.
Physical mapping of a 950-kb region surrounding a locus (D10S102) tightly linked to the MEN2A gene. 总被引:4,自引:0,他引:4
We have constructed a long-range contig of cosmid and YAC clones around D10S102, a locus that is tightly linked to the gene responsible for multiple endocrine neoplasia type 2A (MEN2A). With D10S102 as a starting point, a 360-kb cosmid contig was constructed by bidirectional genomic walking, and at least six fragments from these cosmids showed high sequence homology to other species. Five YAC clones were also isolated at the D10S102 locus, and they formed a contig covering 950 kb of genomic DNA. Furthermore, we obtained six RFLP systems from the contig, which will serve as new resources for fine-scale genetic linkage mapping of the MEN2A locus. 相似文献
70.
Y Itoh A Oguro K Nakamura Y Ishizuka K Yamane 《Bioscience, biotechnology, and biochemistry》1992,56(6):867-871
An artificially inserted extra peptide (21 amino acid peptide) between the B. subtilis alpha-amylase signal peptide and the mature thermostable alpha-amylase was completely cleaved by B. subtilis alkaline protease in vitro. The cleavage to form a mature enzyme was observed between pH 7.5 and 10, but not between pH 6.0 and 6.5, although a similar protease activity toward Azocall was observed between pH 6.0 and 7.5. To analyze the effects of pH on the cleavage, CD spectra at pH 6, 8, and 11 of the NH2-terminally extended thermostable alpha-amylase were analyzed and the results were compared with those of the mature form of the alpha-amylase. It is suggested that the cleavage of the NH2-terminally extended peptide is controlled by the secondary and tertiary structure of the precursor enzyme. Similar cleavage of different NH2-terminally extended peptides by the alkaline protease was also found in other hybrid thermostable alpha-amylases obtained. 相似文献