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1.
Yusuke Nakamura Michio Ogawa Takahiro Nishide Mitsuru Emi Goro Kosaki Seiichi Himeno Kenichi Matsubara 《Gene》1984,28(2):263-270
The nucleotide sequences of the cloned human salivary and pancreatic α-amylase cDNAs correspond to the continuous mRNA sequences of 1768 and 1566 nucleotides, respectively. These include all of the amino acid coding regions. Salivary cDNA contains 200 bp in the 5′-noncoding region and 32 in the 3′-noncoding region. Pancreatic cDNA contains 3 and 27 bp of 5′- and 3′-noncoding regions, respectively. The nucleotide sequence humology of the two cDNAs is 96% in the coding region, and the predicted amino acid sequences are 94% homologous.Comparison of the sequences of human α-amylase cDNAs with those previously obtained for mouse α-amylase genes (Hagenbuchle et al., 1980; Schibler et al., 1982) showed the possibility of gene conversion between the two genes of human α-amylase. 相似文献
2.
Molecular cloning and characterization of human atrial and ventricular myosin alkali light chain cDNA clones 总被引:9,自引:0,他引:9
M Kurabayashi I Komuro H Tsuchimochi F Takaku Y Yazaki 《The Journal of biological chemistry》1988,263(27):13930-13936
We have isolated essentially full-length cDNA clones for atrial (ALC1) and ventricular (VLC1) myosin alkali light chains from a human fetal heart cDNA library. Comparison of overall nucleotide sequences of ALC1 and VLC1 cDNA clones has revealed that, while these two inserts show significant DNA sequence homology (78.4%) with respect to their coding regions, the 5'- and 3'-untranslated regions are highly divergent. Our statistical analysis suggests that human ALC1 and VLC1 diverged approximately 300 million years ago, during the time of separation of birds and mammals. RNA blot analysis shows that ALC1 mRNA is expressed in fetal ventricular and fetal skeletal muscles as well as fetal and adult atrial muscles and VLC1 mRNA is expressed in adult slow skeletal muscle as well as fetal and adult ventricular muscles. Southern blot analysis indicates that each protein is encoded by a single gene. Finally, we show that VLC1 mRNA is induced in pressure-overloaded human atrium. 相似文献
3.
Fractionation of Nitrogen Isotopes during the Uptake and Assimilation of Ammonia by Plants 总被引:9,自引:0,他引:9
Yoneyama Tadakatsu; Omata Tatsuo; Nakata Satoshi; Yazaki Jinya 《Plant & cell physiology》1991,32(8):1211-1217
Two varieties (Nihonbare and Koshihikari) of rice plants (Oryzasativa L.) were grown hydro-ponically with two levels (20 and100 mg N liter 1) of ammonia. Variations in levels ofnatural abundance of 15N (15N) were analyzed in the ammoniaand organic nitrogen of shoots and roots, as well as in theammonia in the culture solution. There was substantial fractionationof nitrogen isotopes during the uptake of ammonia. When plantsabsorbed a large proportion of ammonia from a solution witha low concentration, less negative 15N values in plants andhigh positive 15N values in the ammonia remaining in solutionwere observed. The reverse was found when a smaller fractionof ammonia was absorbed from a solution with a higher concentrationof ammonia. The l5N values of ammonia in shoots and roots werehigher than in the respective constituent organic nitrogen,suggesting the fractionation of nitrogen isotopes during theassimilation of ammonia. Wild-type and mutant cells of the cyanobacterium(blue-green alga) Synechococcus PCC 7942 were grown in nitrate-or ammonia-containing medium as the source of nitrogen. Fractionationof nitrogen isotopes during the uptake of nitrate was limited,whereas that during the uptake of ammonia was considerable.
1 In this report, the term ammonia refers indiscriminately toboth NH3 or NH4+. (Received June 13, 1991; Accepted September 12, 1991) 相似文献
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J L Lin T Asano H Katagiri K Tsukuda H Ishihara K Inukai Y Yazaki Y Oka 《Biochemical and biophysical research communications》1992,184(2):865-870
We engineered the GLUT1 cDNA to delete C-terminal 12 amino acids of encoded GLUT1 protein. This mutated GLUT1 protein expressed in CHO cells by transfection of its cDNA was demonstrated to reside on the plasma membrane by cell surface labeling technique, and retain the transport activity, similar to that of the wild-type GLUT1. In addition, metabolic labeling of the intact cells with 35S indicated that the half-life of the mutated GLUT1 was not significantly different from that of the wild-type GLUT1. These results suggest that C-terminal 12 amino acids of GLUT1 are not important for the transport activity and the stability of the protein. Taken together with our previous results on the mutant without C-terminal 37 amino acids, the amino acids between the 37th and the 13th from the C-terminus appear to be essential for the transport activity. 相似文献
7.
E Okamoto K Imataka J Fujii M Kuro-o K Nakahara H Nishimura Y Yazaki R Nagai 《Biochemical and biophysical research communications》1992,185(1):459-464
Rabbit smooth muscles contain at least three types of myosin heavy chain (MHC) isoforms; SM1, SM2 and SMemb (NMHC-B), the expression of which is developmentally regulated. We have recently reported that smooth muscles with the embryonic phenotype accumulate in the neointimas produced by endothelial denudation or high-cholesterol feeding. In this study, we examined MHC isoform expression in the neointimas and the media of poststenotic dilatation of the rabbit carotid artery, and determined the phenotype of the smooth muscle cell in the dilated segment. We report here that neointimal cells in the dilated segment are smooth muscle cells with the embryonic phenotype as previously reported in our ballooning-injury study. The medial smooth muscles, however, are composed of heterogeneous population of smooth muscles which differ in stage of differentiation as determined by the MHC isoform expression. These results indicate that MHC isoforms are useful molecular markers to identify abnormally proliferating smooth muscles in diseased arteries and to understand the process of atherogenesis occurring following vascular injury. 相似文献
8.
Kenichi Ogasawara Makoto Bannai Naruya Saitou Ryuichi Yabe Kenichi Nakata Michiko Takenaka Kiyoshi Fujisawa Makoto Uchikawa Yoshihide Ishikawa Takeo Juji Katsushi Tokunaga 《Human genetics》1996,97(6):777-783
Polymorphism of the ABO blood group gene was investigated in 262 healthy Japanese donors by a polymerase chain reactions-single-strand conformation polymorphism (PCR-SSCP) method, and 13 different alleles were identified. The number of alleles identified in each group was 4 for A1 (provisionally called ABO*A101, *A102, *A103 and *A104 according to the guidelines for human gene nomenclature), 3 for B (ABO*B101, *B102 and *B103), and 6 for O (ABO*O101, *O102, *O103, *O201, *O202 and *O203). Nucleotide sequences of the amplified fragments with different SSCP patterns were determined by direct sequencing. Phylogenetic network analysis revealed that these alleles could be classified into three major lineages, *A/*O1, *B and *O2. In Japanese, *A102 and *13101 were the predominant alleles with frequencies of 83% and 97% in each group, respectively, whereas in group O, two common alleles, *O101 (43%) and *O201 (53%), were observed. These results may be useful for the establishment of ABO genotyping, and these newly described ABO alleles would be advantageous indicators for population studies. 相似文献
9.
Shinichi Kitamura Takashi Hirano Kenichi Takeo Mitsuru Mimura Kanji Kajiwara Bjrn T. Stokke Tsutomu Harada 《International journal of biological macromolecules》1994,16(6)
The conformation and dilute solution properties of (2→1)-β-d-fructan in aqueous solution were studied by gel permeation chromatography, low-angle laser light-scattering photometry, viscometry, small-angle X-ray scattering and electron microscopy. Fractions covering a broad range of weight-average molecular weights (Mw) from 1.49 × 104 to 5.29 × 106 were obtained from a native sample by ultrasonic degradation and fractional precipitation. For Mw < 4 × 104, the intrinsic viscosity [η] varies with Mw0.71, indicating that the fructan chain behaves as a random coil expanded by an excluded-volume effect in this molecular weight region. For Mw > 105, [η] exhibits an unusually weak dependence on Mw and finally becomes almost independent of molecular weight. This behaviour is interpreted in terms of a globular conformation of the high-molecular-weight fructan molecules. Small-angle X-ray-scattering measurements and electron microscopic observations support this interpretation of the values of [η] observed. 相似文献
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