Immunofluorescence Microscopy of Microtubule Arrangement in Root Cells of Pisum sativum L. var Alaska

The arrangement of wall microtubules (MTs) in Pisum sativumroots was viewed immunofluorescently using cryosectioning. Mostcells in the tip region of pea roots (0–2 mm from tip)had wall MTs arranged transversely to the root axis. In theregion elongating at a higher rate (2–4 mm), wall MTsof epidermal, cortical and stelar cells were all transverselyarranged. In the region of about 5 mm from the tip, in whichcell elongation had already ceased, wall MTs in cortical cellschanged from a transverse to an oblique arrangement in relationto the root axis. Some cells had a crossed arrangement of wallMTs, which was interpreted as representing two sets of unidirectional,oblique wall MTs in opposite cell cortices of a single cell.This change was completed within a region of 1-mm width. Sinceroots elongated at a rate of 0.6 mm h^–1, it means thatthe arrangement of wall MTs changed within 2 h. An oblique arrangementof wall MTs was also observed in stelar cells. As the cellsaged, the oblique arrangement tended to change to a steeperor even a longitudinal one. (Received January 24, 1986; Accepted May 15, 1986)     

Estrogen-mediated induction of a vitellogenin-specific nonhistone chromatin protein in the male chicken liver

Summary Non-histone chromatin proteins prepared from the livers of estrogen-treated and nontreated male chickens were compared by reverse-phase high performance liquid chromatography (RP-HPLC), followed by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results revealed that the hormone-treated male liver chromatin contained a specific protein corresponding to the vitellogenin-specific protein previously purified from the liver of egg-laying hens (Nakayama 1985). The chicken protein, purified further by gel-filtration high performance liquid chromatography (GF-HPLC), showed specific binding activity to DNA fragments carrying a part of the vitellogenin gene. On the basis of similarities in the elution patterns from GF-HPLC and RP-HPLC as well as in the mobility on SDS-PAGE, we concluded that this hormone-induced protein in the male chicken liver was identical to the vitellogenin-specific protein identified in the hen liver, and assumed it to be a specific regulatory protein for the vitellogenin gene expression. The amino acid composition of this chicken protein has been determined.     

O3 Tolerance and the Ascorbate-Dependent H2O2 Decomposing System in Chloroplasts

The relationship between O₃ tolerance and the chloroplast H₂O₂scavenging system (PS I     

Difference in arginine vasopressin responsive cAMP production between apical and basolateral membrane of cultured renal epithelial cells (MDCK)

It has been reported that vasopressin (AVP)-sensitive renal epithelial cell line (MDCK) forms morphologically polarized monolayers when cultured on plates. We studied whether the AVP-responsive cAMP production system would be located solely on the basolateral surface of these cells as has already been shown on the renal tubules. We used two methods to overcome the inaccessibility to the basolateral surface of the cultured cell layer and to study the apical and basolateral surfaces separately. One was culture on collagen sheet and the other was on Millipore filters. Our experiments showed that MDCK cell increased adenosine 3':5'-cyclic monophosphate (cAMP) content prominently only when vasopressin was accessible to the basolateral surface. Accordingly, MDCK cells were shown to have the AVP-responsive cAMP production system predominantly on the basolateral surface of the cell membrane.     

A Highly Sensitive Enzyme Immunoassay for Mouse β Nerve Growth Factor

Abstract: A sensitive two-site enzyme immunoassay system for mouse β nerve growth factor (NGF) was developed, based on the sandwiching of the antigen between anti-mouse β NGF antibody IgG coated to a polystyrene tube and anti-mouse β NGF antibody Fab'-linked β- d -galactosidase (β- d -galactoside hydrolase, EC 3.2.1.23). This method has the following advantages: (a) the procedures are simple and rapid compared to bioassay or two-site radioimmunoassay; (b) antibody Fab'-β- d -galactosidase complex is more stable than ¹²⁵I-labeled antibody; (c) purified β NGF is detectable at a concentration as low as 10 pg/ml. Our enzyme immunoassay was used to examine the levels of NGF in some tissues of mice. The submaxillary gland contained a high concentration of NGF. However, other tissues, such as the heart, brain, and skeletal muscle, and serum did not contain detectable NGF. These results support recent findings by other investigators that NGF was not found in the organs/tissues other than the submaxillary gland of mice.     

Assessment of indoor climate in an apartment by use of a fungal index.

Indoor climate was assessed in an apartment in Isehara City, Kanagawa Prefecture, Japan, by use of a fungal index. The index represents the environmental (climate) capacity to allow fungal growth; it is determined by measuring the growth rate of a biosensor fungus, Eurotium herbariorum J-183. Differences in climate among various parts of the apartment (microclimate) and its changes could be clarified by using the index. The index in the entire apartment was high in summer, low in winter, and intermediate in spring and autumn. According to the part of the apartment, the index was high in water-associated areas and cool areas. This high fungal index in cool areas was caused by the air at the same absolute humidity showing an increase in the relative humidity with a decrease in temperature. Fungal contamination rapidly progressed in areas with a high fungal index in this apartment. A correlation was observed between the fungal index and fungal contamination. Therefore, areas susceptible to fungal contamination can be estimated by use of the fungal index.     

A new yeast gene, HTR1, required for growth at high temperature, is needed for recovery from mating pheromone-induced G1 arrest

A new temperature-sensitive mutant of Saccharomyces cerevisiae was isolated. Arrested cells grown at the nonpermissive temperature were of dumb-bell shape and contained large vacuoles. A DNA fragment was cloned based on its ability to complement this temperature sensitivity. The HTR1 gene encodes a putative protein of 93 kDa without significant homology to any known proteins. The gene was mapped between ade5 and lys5 on the left arm of chromosome VII. The phenotype of the gene disruptant appeared to be strain-specific; disruption of the gene in strain W303 caused the cells to become temperature sensitive. The arrested phenotype here was similar to that of the original is mutant and cells in G2/M phase predominated at high temperature. Another disruptant in a strain YPH background grew slowly at high temperature due to slow progression through G2/M phase, and morphologically abnormal (elongated) cells accumulated. A single-copy suppressor that alleviated the temperature-sensitive defects in both strains was identified as MCS1/SSD1. The wild-type strains W303 and YPH are known to carry defective MCS1/SSD1 alleles; hence HTR1 may function redundantly with MCS1/SSD1 to suppress the temperature-sensitive phenotypes. In addition, based on a halo bioassay, the disruptant strains appeared to be defective in recovery from, or adaptive response to G1 arrest mediated by mating pheromone, even at the permissive temperature. Thus the gene has at least two functions and is designated HTR1 (required for high temperature growth and recovery from G1 arrest induced by mating pheromone).