Chromatic Regulation of Photosystem Composition in the Cyanobacterial Photosynthetic System: Kinetic Relationship between Change of Photosystem Composition and Cell Proliferation

Kinetics of the change of photosystem (PS) composition in cyanobacteriainduced by chromatic light were studied in relation to cellproliferation. The study was made for two unicellular strains,Synechococcus NIBB 1059 and Synechocystis (Aphanocapsa) PCC6714. We found that (1) the change to a higher or lower PS I/IIratio was due to acceleration or suppression of apparent PSI formation, and (2) it progressed on a similar time scale tothat of the cell proliferation. The apparent rate constant ofthe change in the PS I/II ratio was proportional to that ofcell proliferation, µ, when this was low, but at highvalues of µ the increase in the rate constant of the changein the PS I/II ratio became smaller, causing a deviation fromthe linear relationship. Results indicate that under autotrophicconditions, the photoregulated composition change occurs asa result of thylakoid development, which accompanies cell proliferation. (Received June 23, 1986; Accepted December 5, 1986)     

Purification and characterization of a protein that binds to the recombination signal sequence of the immunoglobulin J kappa segment.

A protein that binds to the recombination signal sequence (RS) of the immunoglobulin J kappa segment was purified almost to homogeneity from the nuclear extract of a murine pre-B cell line 38B9. A similar binding protein was found in lymphoid cell lines but not in non-lymphoid cell lines. The binding activity was associated with a polypeptide with a molecular weight of 60,000. DNase I footprinting analysis demonstrated that this binding protein interacted with the heptamer and several 3' bases close to the heptamer. The Kd value of the J kappa RS binding protein to the J kappa RS was 1 nM. One base substitution in the heptamer of the J kappa RS greatly reduced the affinity of the J kappa RS binding protein. The high specificity of the binding site of the J kappa RS binding protein suggests that this protein may be involved in V-J recombination.     

Nudeotide Pools and Purine Metabolism in Tissue Cultures of Wild-Type Datura innoxia and Adenine-Requiring Auxotroph

Cells of the auxotrophic mutant, Ad1, of Datura innoxia requiredadenine, adenosine, or inosine for their growth on solid agarmedium which contained Murashige-Skoog salts, 2,4-dichloro-phenoxyaceticacid, and sucrose. Thirteen purine and pyrimidine nucleotidesin extracts of wild-type and Ad1 cells were separated and quantifiedby HPLC. Levels of ADP-glucose and UMP were significantly higherin Ad1 than in wild-type cells, but those of other nucleotideswas found when Ad1 cells were transferred to fresh medium withoutadenine. The rate of the biosynthesis de novo of purines, asestimated from the rate of incorporation of ¹⁴C from [2-¹⁴C]-glycine and [¹⁴C]formate into adenine nucleotides, was reducedin Ad1 cells to 21 and 13% of the wild-type rate, respectively.The activities involved in the salvage of adenine and adenosinein Ad1 cells were similar to those in wild-type cells. Ad1 cellshad the capability to convert adenine to guanine nucleotidesand guanine to adenine nucleotides. ¹ Part 27 of the series, "Metabolic Regulation in Plant CellCulture". (Received March 7, 1988; Accepted August 3, 1988)     

Changes in hematologic values in 11 months after birth in the cynomolgus monkeys

Changes in hematological values were studied with 131 healthy cynomolgus monkeys aged less than 11 months. The parameters measured were erythrocyte count (RBC), hematocrit value (Ht), mean corpuscular volume (MCV), hemoglobin concentration (Hb), total leucocyte count (WBC), and differential leucocyte count. No remarkable change was found with RBC during the whole period of this study. Relatively high values were obtained with Ht, MCV, and Hb in the newborns aged 0 to 7 days. These values continued to decrease until 3 months of age, after which the values increased again attaining approximately adult levels at 11 months of age. WBC was very high at birth and then decreased to the minimum level at 3 days of age. It was followed by gradual increase until about 4 months of age at which a nearly adult level was attained. Lymphocyte counts were smaller than neutrophil counts on the day of birth. However, this numerical relation was inverted 2 days after birth and the lymphocyte counts became markedly larger than the neutrophil counts about 1 week after birth. Additionally, the values obtained from the cord blood of 6 Cesarean-delivered newborns were compared with those from the blood taken 5 hours after cesarean delivery.     

Interleukin 1 alpha mRNA in virus-transformed T and B cells

IL-1 alpha cDNA clone was isolated from a T cell line infected by the human T lymphotropic retrovirus type-I (HTLV-I/ATLV). We found significant amounts of mRNA hybridizing to IL-1 alpha cDNA not only in HTLV-I-transformed T cells but also in Epstein-Barr Virus-transformed B cells. A part of IL-2 receptor inducing activity in Adult T cell leukemia (ATL) cell line seems to be due to IL-1 alpha.     

Introduction of mouse C epsilon genes into Cos-7 cells and fertilized mouse eggs

A fragment of the cloned gene for the mouse C epsilon chain, coding for the first, second, third, and fourth domains, has been coupled to the SV40 promotor region (pSV2-mC epsilon). About 50 copies of pSV2-mC epsilon or its PvuII-EcoRI fragments were introduced into Cos-7 cells. Expression of PvuII-EcoRI fragments of pSV2-mC epsilon was observed in about 50% of the Cos-7 cells by indirect fluorescence staining. However, no expression of circular pSV2-mC epsilon was observed. About 200 copies of linearized pSV2-mC epsilon with EcoRI were introduced into fertilized mouse eggs. Two of 78 mice born from these eggs had integrated mouse C epsilon genes. Mouse C epsilon gene was shown to be integrated in a tandem array and as intact structures without undergoing gross deletions or rearrangements, judged from the Southern blotting patterns from several restriction enzymes. The first transgenic mouse was mated to a normal male to examine whether mouse C epsilon gene were stably transmitted to progeny. Among 5 mice to which the C epsilon gene had been transmitted, one deleted 5 copies of this gene and another deleted one junction fragment, thus demonstrating relatively unstable transmission. No C epsilon mRNA was detected in the liver, kidney, brain, lung, skeletal muscle, heart, testis, or spleen of a transgenic mouse.     

The Japanese Tsukuba Primate Center for Medical Science (TPC): an outline

The facilities and activities of the Japanese Primate Center at Tsukuba, Japan are described. The Center became partially functional in 1978 and was completed in 1979. The three main aims of the Primate Center are: to quarantine newly imported primate animals, to breed, and to study them.     

IgE heavy chain constant region genes in atopic dermatitis and senile erythroderma patients

By Southern hybridization using a genomic DNA fragment carrying a human IgE heavy chain constant region gene (C ) as a probe, we analyzed the organization of human C genes and their flanking regions in 23 atopic dermatitis and 6 senile erythroderma patients with elevated serum IgE levels, and 6 atopic dermatitis patients with normal IgE levels. On Barn HI, Hind III, and Eco RI digestions, we detected three hybridizable fragments containing three human C genes, C 1, C 2, and C 3, respectively, in all leukocyte DNAs. These fragments were almost identical in size among patients and healthy donors. Pst I digestion generated a genetic polymorphism. We, however, could find no correlation between this polymorphism and the disorders. It was concluded that among the patients and healthy donors, there was no marked difference in the organization of the functional C gene and its flanking region containing a class switch region. Our conclusion cannot rule out the presence of genetic abnormalities of this region in some atopic dermatitis patients which are not resolvable by our method. In the course of this study, we found a novel C -like gene in placenta DNA which differs from the three C genes commonly present in normal human DNA.