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T Harano

Publications and source records attributed to T Harano.

At least 73 records · Page 4Linked to original sources
PubMed1991

[Molecular analysis of an African family with sickle cell disease and alpha-thalassemia-2].

An etiological examination was performed on the DNA of a 13-year-old Zairean girl, who had some abnormalities in hematological and red cell morphological examinations and was homozygote for an abnormal Hb like HbS. DNA was amplified by the PCR method to obtain 1.7 kb size DNA containing the 5' region of the beta globin gene. The amplified DNA was digested with Eco 81 I and electrophoresis of the digest revealed the absence of its active site, which is on codons beta 5-7 (CCTGAGGAG) of the normal DNA. Sequencing of the cloned DNA by the dideoxy method confirmed that the codon beta 6 (GAG, Glu) mutated to a new codon GTG (Val) which is the beta S globin gene producing abnormal HbS. The haplotype of the chromosome having beta S gene was --+---++, which is the most common type in Zaire area. On the other hand, when the genomic DNA was digested with Bgl II or Bam HI and hybridized to an alpha probe, a fragment (16 kb/Bgl II or 10.5 kb/Bam HI) in addition to the normal ones (12.5 and 7.5 kb/Bgl II or 14 kb/Bam HI) was observed. This resulted from the deletion of 3.7 kb from the alpha gene arrangement, which led to alpha-thalassemia-2 (genotype: alpha 3.7-/alpha alpha). A family study demonstrated that her parents were heterozygote for HbS and her father had alpha-thalassemia-2.

Adolescent↗
PubMed1991

[Application of the polymerase chain reaction (PCR) in the diagnosis of Hb S-beta(+)-thalassemia].

Isoelectric focusing of the hemolysate prepared from a two-year-old American black boy with microcytic hypochromia showed the presence of a high percentage (63.3%) of such Hb variant as Hb S, while the levels of Hb A, Hb F and Hb A2 were 20.0%, 12.7%, and 4.0%, respectively. The ratio of the non-alpha-chain to the alpha-chain of the biosynthesized globin chains was 0.49. The variant was identified as Hb S by amino acid analysis of the abnormal peptide (beta T-1) and digestion of DNA amplified by the polymerase chain reaction with enzyme Eco 81 I. This was further confirmed by DNA sequencing. DNA sequencing of a beta-gene without the beta s-mutation revealed a nucleotide change of T to C in the polyadenylation signal sequence AATAAA 3' to the beta-gene, resulting in beta(+)-thalassemia. These results are consistent with the existence of a beta s-gene and a beta(+)-thalassemia gene in trans.

Child, Preschool↗
PubMed1990

[Structural analysis of abnormal hemoglobin by the polymerase chain reaction (PCR) of genomic DNA].

Determination of the primary structure of abnormal Hbs on the basis of DNA sequencing of the globin gene obtained from a carrier of abnormal Hb was performed. DNA obtained from the leukocytes of the peripheral blood was amplified by the polymerase chain reaction (PCR) using the proper amplification primer set. Amplified DNA was digested with two different restriction endonucleases and cloned to vector M 13 mp 18 or mp 19, which had been digested with the same enzymes. DNA sequencing was done by the dideoxy chain termination method using T 7 DNA polymerase, and the abnormal Hbs whose primary structure was determined were as follows: Hb Fukuoka [beta 2 His(CAC/T)----Tyr(TAT)], Hb Machida [beta 6 Glu(GAG)----Gln (CAG)], Hb Hope [beta 136 Gly(GGT)----Asp(GAT)], Hb Hiroshima [beta 146 His(CAC)----Asp(GAC)] and Hb Kodaira [beta 146 His(CAC)----Gln(CAA)]. This method for determining the primary structure of abnormal Hbs might be more effective than the ordinary method, which involves amino acid analysis and amino acid sequencing of the abnormal peptide obtained from abnormal Hb.

DNA↗
PubMed1989

Structure-function relationships in hemoglobin Kariya, Lys-40(C5) alpha----Glu, with high oxygen affinity. Functional role of the salt bridge between Lys-40 alpha and the beta chain COOH terminus.

The epsilon-amino group of Lys-40 alpha forms a salt bridge with the alpha-carboxyl group of beta chain in deoxyhemoglobin and is considered to impose a constraint upon hemoglobin tetramer, stabilizing the T quaternary structure. Hb Kariya, in which Lys-40 alpha is replaced by Glu, provides a unique opportunity to investigate the functional role of this salt bridge. Hb Kariya showed oxygen binding properties characterized by a high affinity, diminished cooperativity, a reduced alkaline Bohr effect, and a decreased effect of phosphates upon oxygen affinity. In deoxyHb Kariya the reactivity of the sulfhydryl groups of cysteins-93 beta with 4,4'-dipyridine disulfide was profoundly enhanced, being comparable to that for normal oxyhemoglobin (oxyHb A). The Soret band spectra, UV derivative spectra, and UV oxyminus-deoxy difference spectra indicated that oxyHb Kariya assumes a quaternary structure similar to that of oxyHb A whereas the T structure of deoxyHb Kariya is destabilized, and Hb Kariya remains predominantly in the R state upon deoxygenation. Resonance Raman scattering by deoxyHb Kariya showed that the Fe-N epsilon(proximal His) bond is less stretched than that of deoxyHb A. These experimental results provide structural basis for explaining the oxygen binding characteristics of Hb Kariya and further give direct evidence that the intersubunit salt bridge between Lys-40 alpha and the beta chain COOH terminus actually contributes to stabilization of the T quaternary structure, thereby playing a key role in cooperative oxygen binding by hemoglobin. The nature of another salt bridge between Asp-94 beta and the COOH-terminal His of beta chain was also discussed in comparison with the salt bridge involving Lys-40 alpha.

2,3-Diphosphoglycerate↗
PubMed1989

Hemoglobin Hope found in a patient with basal cell carcinoma of the genial region.

Hemoglobinopathy was detected in a 72-year-old female with basal cell carcinoma of the genial region during high-performance liquid chromatography of hemolysate for the assay of HbA1c. Structural analysis demonstrated that this abnormal hemoglobin was identical to Hb Hope [beta 136(H14)Gly----Asp]. No clinical or hematological abnormality was observed. A study of the family revealed that a younger sister and two sons of the propositus had the same hemoglobin variant. This is the second observation of Hb Hope in a Japanese family.

Aged↗
PubMed1989

[The molecular basis of HbH disease in a Japanese girl].

Hemoglobin H disease is often caused by deletion of three of the four alpha-globin genes (genotype: --/-alpha). We studied a Japanese girl who had microcytic hypochromic anemia, a decreased alpha/beta globin synthetic ratio and about 8% Hb H in her fresh hemolysate, by means of restriction endonuclease mapping of the alpha-like gene complex (5'-zeta-phi zeta-phi alpha 2-phi alpha 1-alpha 2-alpha 1-theta-3') with zeta- and alpha-specific probes. It was found that the defect of one chromosome was associated with the removal of about 18 kb of DNA, known as --SEA type alpha-thalassemia-1, including the deletion of the part of phi alpha 2, phi alpha 1, alpha 2, alpha 1, and theta globin genes, while the other one was associated with the removal of 3.7 kb of DNA, known as rightward deletion type alpha-thalassemia-2. The results of a family study demonstrated that the deletion haplotype --SEA was inherited from her father's side and the other -alpha 3.7 from her mother's side.

Asian People↗
PubMed1988

Biosynthesis and localization of rat liver microsomal carboxyesterase E1.

One of the microsomal carboxyesterases, carboxyesterase E1, was purified from rat liver to homogeneity. Carboxyesterase E1 is a glycoprotein of high mannose type, and is composed of three identical subunits of 59 kDa each. It is very similar to "esterase pI 6.0" described by Menthein et al. (Arch. Biochem. Biophys. 200, 547-559 (1980)) in molecular weight, amino acid composition, and enzymic activities. Carboxyesterase E1 was found to be evenly distributed between rough and smooth microsomes. The content of the enzyme in microsomes was about 1.5% of total microsomal protein. It was exclusively located on the luminal side of microsomes, and was not detected immunologically in Golgi fractions or serum. In vitro translation of rat liver RNA by reticulocyte lysate showed that carboxyesterase E1 was synthesized preferentially on the bound ribosomes, as a precursor peptide larger than the peptide of the mature enzyme. Carboxyesterase E1 was solubilized from microsomes by treatment with low concentrations of detergents. However, it was not released from microsomes by treatment with a synthetic peptide which made the microsomal membrane permeable to soluble protein molecules. Carboxyesterase E1 is not a soluble luminal protein, and seems to be bound to the luminal surface of the membrane.

Amino Acids↗
PubMed1988

Characterization of abnormalities in the gamma-globin gene arrangements of Japanese newborns.

Cord blood samples from 889 healthy Japanese newborns from three districts of Honshu Island were studied with the purpose of characterizing the gamma-globin genes in the Japanese. The A gamma T gene frequency was 0.159 which is the same as that found elsewhere in Japan. The haplotype of the chromosome with the A gamma T gene was [-- ++ - + (+ or -) (+ or -)] at eight polymorphic sites. Data from analyses of DNA and the proportion of gamma chains in Hb F showed the existence of various kinds of gamma-globin gene arrangements; six genotypes were observed for individuals with high G gamma values and triple or quadruple gamma-globin gene arrangements, and seven genotypes for babies with low G gamma values and a single gamma-globin gene. The in vivo expression of the gamma-globin gene located at the third or fourth position in the multiple gene arrangement was found to be about 5% and 2.5% of the total, respectively. The haplotype for the chromosomes with a triple gamma-globin gene was [+ --(-)---- +], but that for the chromosomes with a single gamma-globin gene remains unclear. In addition, a new type of Bgl II polymorphism in the G gamma-globin gene was observed.

Fetal Blood↗
PubMed1987

Effect of amino acid at the beta 6 position on surface hydrophobicity, stability, solubility, and the kinetics of polymerization of hemoglobin. Comparisons among Hb A (Glu beta 6), Hb C (Lys beta 6), Hb Machida (Gln beta 6), and Hb S (Val beta 6).

Surface hydrophobicity, stability, solubility, and kinetics of polymerization were studied using hemoglobins with four different amino acids at the beta 6 position: Hb A (Glu beta 6), Hb C (Lys beta 6), Hb Machida (Gln beta 6), and Hb S (Val beta 6). The surface hydrophobicity increased in the order of Hb C, Hb A, Hb Machida, and Hb S, coinciding with the hydrophobicity of the amino acid at the beta 6 position. Solubility of the oxy-form of these hemoglobins decreased in relation to increases in their surface hydrophobicity, suggesting that the solubility is controlled by the strength of hydrophobicity of the amino acid at the beta 6 position. The solubility of the oxy-form of these hemoglobins is always higher than that of the deoxy-form. There is a similar linear relationship between the solubility and surface hydrophobicity among deoxyhemoglobins A, C, and Machida. However, the solubility of deoxy-Hb S deviated significantly from the expected value, indicating that the extremely low solubility of deoxy-Hb S is not directly related to the hydrophobicity of the beta 6 valine. Kinetic studies on the polymerization of deoxy-Hb Machida revealed a distinct delay time prior to polymerization. This confirms our previous hypothesis that beta 6 valine is not responsible for the delay time prior to gelation. The kinetics of the polymerization of 1:1 mixtures of sickle and non-sickle hemoglobins were similar to those of pure Hb S, suggesting that only one of the two beta 6 valines is involved in an intermolecular contact. In mixtures of equal amounts of Hb S and Hb A, Hb C, or Hb Machida, half of the asymmetrical AS, SC, and S-Machida hybrid hemoglobins behaved like Hb S during nucleation, while the other half behaved like the non-sickle hemoglobin.

Drug Stability↗
PubMed1987

The beta-delta crossover leading to the beta delta hybrid gene of hemoglobin P-Nilotic is located within 54 base-pairs of the 5' end of exon 2 or between codons 31 and 50.

The crossover region of the beta delta hybrid gene of the hemoglobin variant Hb P-Nilotic was defined in detail through cloning and sequencing of appropriate DNA segments. The crossover must have occurred without loss of bases within a 54 base-pair stretch of DNA between bases 275 and 330 (or between amino acid residues 31 and 50), indicating that the exon 1 and IVS-1 originate from beta, and exon 2, IVS-2 and exon 3 from delta. The data support the speculation that the IVS-1, in contrast to IVS-2, has no effect on the expression of this hybrid gene.

Adult↗