Complete nucleotide sequence of mouse immunoglobulin mu gene and comparison with other immunoglobulin heavy chain genes

We have determined the complete nucleotides sequence (2168 bases) of the immunoglobulin mu gene cloned from newborn mouse DNA. The cloned 13kb fragment contained the entire constant region gene sequence that is interrupted by three intervening sequences at the junction of domains as previously shown in the gamma 1, gamma 2 b and alpha genes. The amino acid sequence predicted by the nucleotide sequence agrees with that of the mu chain secreted by a myeloma MOPC104E except for 8 residues out of 448 residues. The homologous domains of the mu, gamma 1 and gamma 2b genes are more similar to each other than the different domains of the mu genes are. The result implicates that the class of the immunoglobulin heavy chain genes diverged after the heavy chain genes established the multi-domain structure. The short intervening sequences of the mu and gamma genes are more conserved than the coding sequences except for the COOH-terminal domains. The results implicate that the nucleotide sequence of the intervening sequence is under selective pressure, possibly to maintain a secondary structure of the nuclear RNA to be spliced.     

Synthesis of D-cysteine from 3-chloro-D-alanine and hydrogen sulfide by 3-chloro-D-alanine hydrogen chloride-lyase (deaminating) of Pseudomonasputida

Synthesis of D-cysteine from 3-chloro-D-alanine and hydrogen sulfide is catalyzed by highly purified 3-chloro-D-alanine hydrogen chloride-lyase from $\text{Pseudomonas}\text{putida}$. The synthetic reaction proceeds optimally at pH 8.5, as a function of enzyme concentration and incubation time. The enzymatically synthesized D-cysteine was isolated from the large scale reaction mixture and identified by physicochemical means.     

Changes in distribution of molecular weight forms of biologically active and immunoreactive adrenocorticotropic hormone after adrenalectomy in rat anterior pituitary

The concentration of ACTH in extracts of rat anterior pituitary was measured by both radioimmunoassay and bioassay at different stages following adrenalectomy. Both types of ACTH activity decreased the day immediately following adrenalectomy but increased gradually afterwards. Immunological ACTH activity increased to 250% of the control value and biological ACTH activity increased to 490% of control value 3 weeks after adrenalectomy. The increase in biological ACTH activity occurred earlier, and the rate of increase was greater, than that of the immunological ACTH activity. The distributions of molecular weight forms of ACTH in extracts of anterior pituitary lobes was determined by gel filtration. Three molecular weight forms of immunoassayable ACTH were detected. Biological ACTH activity appeared in the 2nd and the 3rd peaks. A striking change was observed after adrenalectomy in the distribution of biologically active forms of ACTH. The ratio of biological ACTH activity to immunological ACTH activity in each peak changed at various stages after adrenalectomy. This indicated the heterogenous nature of the ACTH included in each peak. At 2 and again at 3 weeks, biological activity markedly increased until it exceeded the immunological ACTH activity in the 2nd peak. Dexamethasone had little influence on the elution profile of either immunoassayable and biologically active ACTH in gel filtration. Adrenalectomy may possibly have an effect on the intracellular posttranslational processing of ACTH precursors which leads to the development of biological ACTH activity.     

Nucleotide sequence of 5S ribosomal RNA from Lingula anatina. A study on the molecular evolution of 5S ribosomal RNA from a living fossil

By chromatography on columns of DEAE-Sephadex A-50 and Sephadex G-100, and electrophoresis on polyacrylamide gel, 5S rRNA was purified from a low-molecular-weight RNA fraction extracted from the total tissues of Lingula anatina. Complete digests of the 5S rRNA with RNase T1 [EC 3.1.4.8] and pancreatic RNase [EC 3.1.4.22] were sequenced by conventional column chromatography procedures. The nucleotide sequence of this RNA was determined mainly by a chemical method for sequencing the RNA 3' end-labeled with 32P (1), with the complement of the oligonucleotide catalog obtained by the complete RNase digestions of the RNA. By comparing the sequences of several invertebrate, vertebrate, and Chlorella 5S rRNAs, a phylogenic tree of the rRNAs was constructed and the time of divergence of Lingula was estimated.     

Dystrophin in rod spherules; submembranous dense regions facing bipolar cell processes

 It is known that the retina contains the protein dystrophin in the ribbon synapse, but the ultrastructural analysis is not yet fully elucidated. Our previous study reported that dystrophin is localized under the rod cell membranes in rat retinas. In the present study, we have investigated the relationship between dystrophin-rich regions of rod cell membranes and other neuronal processes in mouse retinas with a monoclonal antibody raised against the human dystrophin C-terminus. Immunoblotting, immunofluorescence stainings, and immunoelectron microscopy were employed. Immunoblotting analysis indicated that mouse retinas possessed some of the dystrophin isoforms of approximately 260 kDa, 140 kDa, and 70 kDa molecular weight. Confocal images showed a punctate appearance in the outer plexiform layer, as previously described. Immunoelectron microscopy showed that dystrophin immunoreactive products were always observed at submembranous dense regions of the rod spherule abutting bipolar processes. These results suggest that retinal dystrophin may be closely involved in signal transmission from rods to bipolar cells. Accepted: 7 May 1997     

The Electrophoretical Analysis of Esterase and Catalase and Its Use in Taxonomical Studies of Mycobacteria

The zymogram patterns of esterases and catalases of mycobacterial strains were studied using the thin layer agar electrophoresis. Though there were some variations, Mycobacterium hominis, M. bovis, M. kansasii, M. fortuitum, M. runyonii, M. avium, M. phlei and M. smegmatis seemed to show species-specific patterns consisting of 2 to 6 esterase bands and one or more catalase bands. The patterns of scotochromogens and nonchromogens were rather variable.     

Leukemia in Animals and Man

General comparative aspects of leukemia were reviewed. Leukemia in adult cattle occurs frequently within certain multiple case herds. Cattle in these herds often have persistent lymphocytosis and increased numbers of atypical lymphocytes in blood. Attempts are being made to demonstrate the frequency in which this is a “pre-leukemic” or “perileukemic” condition.With the recognition of viral causative agent(s) in chickens, laboratory rodents and cats, there is increased interest in the leukemia of dogs, cattle and other animals, for the disease in these animals may serve as valuable models in the study and isolation of human leukemogenic agents.Epidemiologic and clinicopathologic aspects of animal leukemias share comparative similarities with themselves and with lymphoreticular neoplasms of man. Causative factor(s) probably act on the host, regardless of species, in a similar fashion. It is not likely, but neither improbable, that leukemia in domesticated animals and leukemia in man share common causal relationships.