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A Inoue

Publications and source records attributed to A Inoue.

At least 595 records · Page 33Linked to original sources

Nucleotide sequence of cloned cDNA for bovine corticotropin-beta-lipotropin precursor.

The nucleotide sequence of a 1,091-base pair cloned cDNA insert encoding bovine corticotropin-beta-lipotropin precursor mRNA is reported. The corresponding amino acid sequence indicates that the precursor protein consists of repetitive units and includes a third melanotropin sequence in its cryptic portion. Pairs of lysine and arginine residues separate the component peptides of the precursor.

Adrenocorticotropic Hormone↗

Purification and characterization of the messenger RNA coding for bovine corticotropin/beta-lipotropin precursor.

The mRNA coding for the common precursor of corticotropin and beta-lipotropin has been purified to homogeneity from neurointermediate lobes of bovine pituitaries. The homogeneity of the mRNA preparation is evidenced by analysis of its translation product, electrophoresis on polyacrylamide gel in the presence of formamide and analysis of the kinetics of hybridization with its cDNA. The purification procedure involves the isolation of RNA from membrane-bound polysomes, chromatography on oligo(dT)-cellulose and on poly(U)-Sepharose and sucrose density gradient centrifugation. The mRNA has a molecular weight of approximately 450000, equivalent to approximately 1360 nucleotides in length, and contains a polyadenylate sequence with an average length of 68 nucleotides. The size of the mRNA is sufficiently large to encode the corticotropin/beta-lipotropin precursor.

Adrenocorticotropic Hormone↗

Psoas transfer for the treatment of congenital dislocation of the hip.

Since 1965, anterolateral transfer of the psoas muscle has been employed by us as a routine surgical treatment for congenital dislocation of the hip joint. The transfer was carried out in association with open reduction in those patients in whom an intracapsular obstruction was evident, but corrective measures for acetabular dysplasia or cervicocapital deformity of the femur were not performed in this series. We treated 87 hip joints with this procedure from 1965 to 1973. In 38 hip joints, both open reduction and the psoas transfer were followed up for an average of 8 years. Thirteen hip joints with open reduction alone were included as controls. Position of the femoral head and development of the acetabulum and proximal end of the femur were assessed on X-rays, mainly after Severin's criteria. Redislocation was not encountered. Fifty percent of the hip joints with open reduction and the psoas transfer were classed as grade I or II. This figure is higher than that of controls, to which 23% were classed as grade I or II. Better concentricity of the head was achieved as determined by the CE angle (Wiberg). Development of acetabulum occurred when the transfer had been carried out in children under 1 year of age and was less likely in the older children. The detorsional effect of the psoas transfer remained questionable since detorsion in the transferred group did not exceed that of the controls.

Anthropometry↗

Identification of myosin in a flowering plant, Egeria densa.

A myosin-like protein was extracted and partially purified from a flowering plant, Egeria densa. It had no p-nitrophenyl phosphatase activity, but exhibited EDTA(K+)-ATPase [EC 3.6.1.3] activity at high ionic strength. Its molecular weight as estimated by gel filtration was 4-5 X 10(5). The presence of a heavy chain (MW = about 1.8 X 10(5)) was indicated by SDS-gel electrophoresis. Egeria myosin aggregated in an environment of low ionic strength and formed bipolar filaments. It bound with skeletal muscle F-actin with a periodicity of 40 nm.

Actins↗

Modification of cardiac and smooth muscle myosins with 2,4,6-trinitrobenzenesulfonate. Evidence for differences in structure around the active sites of cardiac, smooth, and skeletal muscle myosin ATPase.

Myosins purified from cardiac (porcine heart) and smooth (chicken gizzard) muscles were modified with 2,4,6-trinitrobenzenesulfonate (TNBS) and the effects on the kinetic properties of myosin ATPase [EC 3.6.1.3] were studied. The following results were obtained. 1. About 0.5 mol of TNBS per mol of myosin head was incorporated rapidly, irrespective of the presence of PP1 (2mM), into both types of myosin studied. 2. The size of the initial burst of P1 liberation for both myosins was found to be 0.5--0.6 mol/mol head. 3. The rapid incorporation of TNBS into cardiac muscle myosin was accompanied by a rapid decrease in the size of the initial P1 burst, and it was completely lost after modification for 20 min. However, smooth muscle myosin retained its P1 burst. 4. The EDTA (K+)-ATPase activity of both myosins modified in the presence or absence of PP1 decreased sharply with incorporation of TNBS. 5. Superprecipitation and ATPase activity of reconstituted actomyosin from cardiac myosin and skeletal F-actin decreased only after 10 min of modification with TNBS in the absence of PP1. 6. The spectra of TNP bound to myosins from cardiac and smooth muscles were unchanged by the addition of PP1. The above findings are compared with those previously obtained for skeletal muscle myosin [Miyanishi, T., Inoue, A., & Tonomura, Y. (1979) J. Biochem. 85, 747--753], and the structural and functional differences among the myosins derived from skeletal, cardiac, and smooth muscles are discussed.

Actins↗

A histological study of idiopathic avascular necrosis of the head of the femur.

We have studied the histological appearances of forty femoral heads with idiopathic avascular necrosis. The characteristic histopathological changes of recurrent necrosis were present in 83 per cent. Recurrent necrosis occurred widely after revascularisation had progressed as far as the subchondral zone. The aetiology of idiopathic avascular necrosis of the femoral head may be a chronic condition which produces repeated infarction. The deformation and incomplete revascularisation of the femoral head may be due to repeated episodes of infarction as well as to mechanical factors related to weight-bearing.

Adolescent↗

Functional implications of the two-headed structure of myosin.

This review summarizes the results obtained by biochemical and physiological studies on the functional implications of the two-headed structure of the myosin molecule. Our nonidentical two-head hypothesis of myosin is supported by biochemical studies on myosin ATPase. The reaction mechanism of the Mg2+-ATPase reaction catalyzed by one head of the myosin molecule is shown to be different from that catalyzed by the other head, and the reaction intermediate, MPADP, is produced in head B but not in head A. Evidence for differences in the chemical structures of the two heads of myosin is also presented. The myosin preparation is shown to be a mixture of homodimers with respect to its g-chain composition, but every homodimer has the non-identical two heads, B and A. Furthermore, the molecular mechanism for acceleration of the Mg2+-ATPase reaction by F-actin and that for its control by Ca2+ ions and Mg2+-ATP are discussed, based on the nonidentical two-head hypothesis of the myosin molecule. It was shown that the formation and decomposition of the key intermediate, A(B)MPADP are required for tension development and shortening. One cycle of ATP hydrolysis by crossbridges synchronously initiated by a rapid stretch or a sudden release of a slow stretch, indicating that the probability of dissociation of a crossbridge by its interaction with ATP depends on its angular position. It is also demonstrated that rotation of the base of nucleoside triphosphate about the glycosyl bond is essential for formation of MPXDP from M2XTP, as well as for muscle contraction. Based on these biochemical and physiological studies on the movement of the myosin head in muscle contraction, a molecular mechanism for muscle contraction is proposed.

Actomyosin↗

Construction of bacterial plasmids that contain the nucleotide sequence for bovine corticotropin-beta-lipotropin precursor.

mRNA that encodes the common peptide precursor for the hormones corticotropin and beta-lipotropin was purified from the neurointermediate lobe of bovine pituitaries, and double-stranded cDNA species synthesized from this template were cloned in Escherichia coli X1776 by inserting them into the Pst I endonuclease cleavage site of the pBR322 plasmid using poly(dG)poly(dC) homopolymeric extensions. Certain of the cloned cDNA inserts contain nucleotides corresponding to the complete amino acid sequence of bovine corticotropin and a coding sequence that corresponds to at least the first portion of bovine beta-lipotropin. The nucleotide sequences coding for corticotropin and beta-lipotropin are separated on the cDNA by a 6-base-pair sequence encoding lysine and arginine, indicating that the carboxyl terminus of corticotropin is connected on the precursor peptide with the amino terminus of beta-lipotropin by these two amino acids. In addition, the cloned cDNA insert is characterized by an unusually high C+G nucleotide base content as well as by a number of DNA sequence duplications.

Adrenocorticotropic Hormone↗