N-Terminal Amino Acid Sequence and Processing Site of Sweet Potato Cytochrome c Oxidase Subunit II

The N-terminal amino acid sequence of sweet potato cytochromec oxidase subunit II polypeptide was determined. Comparisonsbetween the sequence and amino acid sequences deduced from thenucleotide sequences of other higher plant subunit II genesindicate a post-translational clevage of N-terminal extensionpart. ¹Present address: Institute of Low Temperature Science, HokkaidoUniversity, Sapporo, 060 Japan. (Received June 13, 1989; Accepted September 8, 1989)     

Differences in lectin binding patterns of normal human endometrium between proliferative and secretory phases

Lectin binding patterns in normal human endometrium were examined by light and electron microscopy using seven different lectins (ConA, WGA, RCA, PNA, UEA-1, DBA, and SBA). For light microscopic observations, criteria based on the incidence and intensity of cells positive for the lectin staining were adopted to evaluate the different staining patterns of the proliferative and secretory endometria obtained by the avidin-biotin-peroxidase complex (ABC) technique. At the light microscopic level, ConA, WGA, and RCA stained endometrial glandular cells in both phases. The number of PNA-positive cells with the binding sites entirely limited to the apical surface tended to be reduced slightly in the secretory phase. UEA-1 weakly stained the apical surface of glandular cells in the proliferative phase but not in the secretory phase. Among the lectins used in this study, DBA and SBA displayed remarkable changes between the phases. That is, in the proliferative phase they produced only a faint or slight positive stain at the apical surface, but the incidence and intensity of DBA- and the SBA-positive glandular cells increased in the secretory phase. By electron microscopy, the reaction product of ConA was observed in the plasma membrane, endoplasmic reticulum, nuclear envelope, and the Golgi apparatus, and the binding sites of RCA and DBA were observed in the plasma and Golgi membranes. Between both phases, the reactivity of ConA and RCA showed almost no change. However, the secretory endometrial cells containing the DBA-positive Golgi apparatus were markedly increased in number compared with the proliferative ones bearing the lectin-positive organelles.(ABSTRACT TRUNCATED AT 250 WORDS)     

Establishment and characterization of a human chorionic gonadotropin (hCG) producing cell line (RTSG) from an ovarian epithelial cancer

A new cell line designated RTSG established in vitro from the pleural effusion of a patient with metastatic ovarian epithelial cancer has been subcultured 46 times for more than 2 years. The cells grew in a monolayered sheet, showing a tendency to pile up, with the population doubling in 48 hrs. Electron-microscopically, desmosomes were characteristically observed, suggesting the cells were of epithelial origin. Chromosomal analysis revealed aneuploidy with a tetraploid mode. The heterotransplanted tumors in nude mice were histopathologically classified as a poorly differentiated adenocarcinoma, whereas the original tumor consisted mainly of mucinous and serous cystadenocarcinoma and only partly of poorly differentiated adenocarcinoma. The cells secreted hCG (38.8 mIU/day/10(6) cells) and beta-hCG (6.1 ng/day/10(6) cells) in spent medium. Immunocytologic +-and-histochemical staining for tumor markers of the original tumor, the cultured cells and the transplanted tumors also revealed the localization of not only hCG and beta-hCG but also CA19-9 and CA-125 whose values had been elevated in the preoperative serum (hCG: 10 mIU/ml, CA19-9: 6,400 U/ml, CA-125: 225 U/ml). Results of PAS, Alcian-blue and Mucicarmine strains indicated that most of the PAS-positive substances in the cultured cells and the transplanted tumors were consistent with glycogen while the original tumor mainly contained mucin except for the lesion of poorly differentiated adenocarcinoma with glycogen. These results suggested that the cultured cells might originate from poorly differentiated adenocarcinoma cells in the original tumor.     

The regions of alpha-neurotoxin binding on the extracellular part of the alpha-subunit of human acetylcholine receptor

A set of 18 synthetic uniform overlapping peptides spanning the entire extracellular part (residues 1–210) of the -subunit of human acetylcholine receptor were studied for their binding activity of¹²⁵I-labeled -bungarotoxin and cobratoxin. A major toxin-binding region was found to reside within peptide 122–138. In addition, low-binding activities were obtained with peptides 34–49 and 194–210. It is concluded that the region within residues 122–138 constitutes a universal major toxin-binding region for acetylcholine receptor of various species.     

The regions of α-neurotoxin binding on the extracellular part of the α-subunit of human acetylcholine receptor

A set of 18 synthetic uniform overlapping peptides spanning the entire extracellular part (residues 1–210) of the α-subunit of human acetylcholine receptor were studied for their binding activity of¹²⁵I-labeled α-bungarotoxin and cobratoxin. A major toxin-binding region was found to reside within peptide α122–138. In addition, low-binding activities were obtained with peptides α34–49 and α194–210. It is concluded that the region within residues α122–138 constitutes a universal major toxin-binding region for acetylcholine receptor of various species.     

Distribution and possible intergradation betweenMacaca tonkeana andM. ochreata at the borderland of the species in Sulawesi

Morphological observations of pet and wild monkeys were made in the area that was inferred to be the borderland betweenMacaca tonkeana andM. ochreata in Sulawesi. Almost all individual monkeys could be classified into one of two species by their external characteristics. The possible borderland was estimated to extend from the La River in the east and to around Karaena River in the west. These two species may make contact in the forest in the western area of the borderland. Some external characteristics exhibited wide individual variations in the two species. Some monkeys originating from the borderland showed external characteristics that were intermediate between those of the two species. The possible intergradation between these two species is discussed in terms of the morphological variations found in the two species.     

Silence of streptomycin 6-phosphotransferase gene derived by incubation at a high temperature inStreptomyces griseus

Summary The bald mutants from streptomycin (SM)-producingStreptomyces griseus 2247 obtained by incubation at high temperature (36° C), designated as HT strains, lost resistance to their own antibiotic and scarcely produced the antibiotic. Although SM susceptibility in the mutant was due to loss of SM 6-phosphotransferase activity produced in the cell, the gene coding for the enzyme cloned from an HT strain was surely expressed inS. lividans 1326 as a host. Northern blot analysis showed that the corresponding RNA is not detected in the mutant, indicating that though the gene encoding SM 6-phosphotransferase, at least, the structural gene is not deleted in the cell, the expression is silent.     

Aberrant porphyrin metabolism in hepatocellular carcinoma

In 15 patients with hepatocellular carcinoma (HCC) and 14 patients with liver cirrhosis (LC), urinary excretions of delta-aminolevulinic acid (ALA), porphobilinogen (PBG), uroporphyrin (UP), coproporphyrin (CP), and erythrocyte contents of CP and protoporphyrin (PP) were examined. In patients with HCC, urinary excretions of ALA and PBG and erythrocyte contents of CP and PP were not increased, but urinary excretions of UP and CP were significantly increased more than those of LC patients. Urinary excretions of UP and CP had no correlations with liver function tests and excretion of UP correlated slightly with blood hemoglobin level. After administration of ALA intravenously, urinary excretions of UP and CP were clearly increased in patients with HCC compared to normal controls. A Red fluorescent area was present at the cancerous area but not in the noncancerous cirrhotic area in a patient with HCC. These results suggest that aberrant porphyrin metabolism occurred in patients with HCC compared to other liver diseases.     

Linear, Single-Stranded Deoxyribonucleic Acid Isolated from Kilham Rat Virus

Kilham rat virus (KRV) was grown in a rat nephroma cell line and was purified by two isopycnic centrifugations in cesium chloride. The virus contains single-stranded deoxyribonucleic acid (DNA) with a molecular weight of approximately 1.6 x 10(6). The DNA was extracted from the virion by both phenol extraction and by 2% sodium dodecyl sulfate at 50 C. KRV DNA, extracted by both procedures, was observed in an electron microscope by using a cytochrome c or diethylaminoethyldextran monolayer. The DNA was also exposed to exonuclease I, an enzyme which hydrolyzes specifically linear, single-stranded DNA. Hydrolysis of 70 to 80% of the DNA was observed. Both the enzymatic and the electron microscope studies support the conclusion that extracted KRV DNA is a single-stranded, linear molecule. The length of the DNA was measured in the electron microscope and determined to be 1.505 +/- 0.206 mum.