A physiological study on acetylcholine receptor expressed in Xenopus oocytes from cloned cDNAs.

Nicotinic ACh receptor was expressed in Xenopus oocytes by injecting mRNAs produced from cloned cDNAs encoding the four subunits of ACh receptor of Torpedo californica. ACh responses recorded from oocytes 3 days after injection of the mRNAs were reversibly blocked by d-tubocurarine (1-2 microM), indicating that the newly synthesized receptor is of nicotinic type. The reversal potential of ACh response was found at around -1 - -5 mV.

Benign mesenchymoma of the sole.

Benign mesenchymoma is a mixed tumor that has at least two mesenchymal components in addition to fibrous tissue. A case of benign mesenchymoma of the sole in a 7-year-old boy is presented. The literature is reviewed and discussed.

Expression of functional acetylcholine receptor from cloned cDNAs.

The cloned cDNAs encoding the four subunits of the Torpedo californica acetylcholine receptor, each carried by a simian virus 40 vector, direct the synthesis of the functional receptor in a combined expression system consisting of COS monkey cells and Xenopus oocytes. Our results suggest that all four subunits are required to elicit a normal nicotinic response to acetylcholine, whereas only the alpha-subunit is indispensable for alpha-bungarotoxin binding activity.

Sequence requirement for transcription in vitro of the human corticotropin/beta-lipotropin precursor gene.

Using HeLa whole cell extracts, we have demonstrated that transcription in vitro of the cloned human and bovine corticotropin/beta-lipotropin precursor genes is initiated accurately and efficiently. DNA sequences required for promoter function have been assessed by using a series of 5'-deletion mutants of a fusion gene that contains the 5'-flanking sequence and capping site of the human corticotropin/beta-lipotropin precursor gene and the structural sequence of the herpes simplex virus thymidine kinase gene. The results obtained have shown that the region between 22 base pairs and 35 base pairs upstream from the capping site is essential for the correct and efficient transcriptional initiation in vitro.

Isolation and characterization of the mouse corticotropin-beta-lipotropin precursor gene and a related pseudogene.

Two mouse genomic DNA sequences homologous with human corticotropin-beta-lipotropin precursor gene sequences have been cloned. One of them represents the functional corticotropin-beta-lipotropin precursor gene, which exhibits a structural organization similar to those of its bovine and human counterparts. The other represents a pseudogene that corresponds to the functional mouse gene sequence encoding the carboxy-terminal 143 amino acid residues (including corticotropin and beta-lipotropin) and the 3'-untranslated region.

Sequence requirement for transcription in vivo of the human preproenkephalin A gene.

The nucleotide sequence of the 5'-flanking region of the cloned human preproenkephalin A gene, extending to 949 bp upstream of the capping site, has been determined. The preproenkephalin A gene, when joined with an SV40 vector and introduced into COS monkey cells, is efficiently transcribed from its own promoter. To assess the DNA sequence required for promoter function, we have constructed a series of 5'-deletion mutants of a fusion gene that consists of the 949-bp 5'-flanking sequence and capping site of the preproenkephalin A gene and the structural sequence of the herpes simplex virus thymidine kinase gene.

Left ventricular-right atrial communication with an aneurysm of the atrioventricular membranous septum. A case report.

A 40-year-old man with combination of left ventricular-right atrial communication and aneurysm of the atrioventricular membranous septum is presented. A supravalvular type defect, 14 X 15 mm in size, was closed with a Teflon patch. An oval shaped aneurysm of the atrioventricular membranous septum, 20 X 17 mm in size was also noted, but was left untouched.

DNA sequences required for transcription in vivo of the human corticotropin-beta-lipotropin precursor gene.

The cloned human corticotropin-beta-lipotropin precursor gene, when joined with an SV40 vector and introduced into COS monkey cells, is transcribed from its own promoter. The DNA sequences required for promoter function have been identified by using 5' deletion mutants of the fusion gene AT which contains the 5'-flanking sequence and capping site of the human corticotropin-beta-lipotropin precursor gene and the structural sequence of the herpes simplex virus thymidine kinase gene. The deletion of the sequence located between 53 and 59 bp upstream of the capping site enhances the transcription approximately 3-fold, while the deletion of the TATA box region abolishes the transcription.

Yeast mutants defective in acetyl-coenzyme A carboxylase and biotin: apocarboxylase ligase.

Among more than 7000 mutants of Saccharomyces cerevisiae, requiring saturated fatty acids, 61 acetyl-CoA-carboxylase-deficient strains have been identified. According to their mutual complementation characteristics these mutants have been assigned to two different genes, acc1 and acc2. Both acetyl-CoA carboxylase genes are unlinked to each other and to the fatty acids synthetase genes fas1 and fas2.

Involvement of long-chain acyl coenzyme A for lipid synthesis in repression of acetyl-coenzyme A carboxylase in Candida lipolytica.

Mutant strains of Candida lipolytica defective in acyl-CoA synthetase II [acid:CoA ligase (AMP-forming), EC 6.2.1.

Acyl-coenzyme-A synthetase I from Candida lipolytica. Purification, properties and immunochemical studies.

Acyl-coenzyme-A synthetase I from Candida lipolytica has been purified to homogeneity as evidenced by polyacrylamide gel electrophoresis in the presence and absence of dodecylsulfate as well as by Ouchterlony double-diffusion analysis. The purification procedure involves resolution of cellular particles with Triton X-100 and chromatography on phosphocellulose, Blue-Sepharose and Sephadex G-100. The purified enzyme exhibits a specific activity of 20--24 U/mg protein at 25 degree C, which is about 100-fold higher than those of long-chain acyl-CoA synthetases hitherto reported.

Subcellular localization of two long-chain acyl-coenzyme-A synthetases in Candida lipolytica.

Studies have been made on the subcellular localization of two long-chain acyl-coenzyme-A synthetases as well as glycerolphosphate acyltransferase and the acyl-CoA-oxidizing system in Candida lipolytica grown on oleic acid. Acyl-CoA synthetase I is distributed among different subcellular fractions, including microsomes and mitochondria where glycerolphosphate acyltransferase is located. On the other hand, acyl-CoA synthetase II is localized in microbodies where the acyl-CoA-oxidizing system is located.

Radical repair of total anomalous pulmonary venous drainage with atrial and ventricular septal defects.

An eleven year old patient with TAPVD, ASD and VSD with left to right shunt who underwent successful total correction is presented. Diagnosis, operative technique and the pertinent literature are briefly discussed.

Candida lipolytica mutants defective in an acyl-coenzyme A synthetase: isolation and fatty acid metabolism.

Mutant strains of Candida lipolytica defective in an acyl-CoA synthetase [acid:CoA ligase (AMP-forming); EC 6.2.1.

Evaluation of surgical treatments for the major lesion of bilateral silicotuberculosis.

The present communication deals with the follow-up study of 24 patients with bilateral silicotuberculosis in whom only unilateral operation was carried out for major lesions. The operative procedure consisted of pulmonary resection, thoracoplasty or combined operation such as cavernostomy, intracavitary filling of a pedunculated muscle flap and thoracoplasty. The follow-up period ranged 1 year to 12 years and 5 months.

Acetyl-coenzyme-A carboxylase of Candida lipolytica. 2. Regulation of cellular content and synthesis of the enzyme.

The level of acetyl-coenzyme-A carboxylase activity in Candida lipolytica undergoes large variations depending upon the carbon source on which the yeast is grown. Cells grown on n-alkanes or fatty acids exhibit a lower activity level than do cells grown on glucose. Among the n-alkanes and fatty acids tested, n-heptadecane, n-octadecane, oleic acid and linoleic acid reduce the enzyme activity to the lowest levels, which are 16-18% of the activity level in glucose-grown cells.

Acetyl-coenzyme-A carboxylase of Candida Lipolytica. 1. Purification and properties of the enzyme.

Acetyl-coenzyme-A carboxylase has been isolated in homogeneous form from Candida lipolytica. The homogeneity of the enzyme preparation is evidenced by analytical ultracentrifugation, dodecyl-sulfate-polyacrylamide gel electrophoresis and Ouchterlony double-diffusion analysis. The purified enzyme exhibits a specific activity of 8.