Changes in levels of mRNAs of transforming growth factor (TGF)-β1, -β2, -β3, TGF-β type II receptor and sulfated glycoprotein-2 during apoptosis of mouse uterine epithelium

To examine the roles played by transforming growth factors (TGF)-β1, -β2, -β3, and TGF-β type II receptors in the induction of apoptosis in the mouse uterine epithelium after estrogen deprivation, we investigated the expression of their mRNAs and the mRNA of sulfated glycoprotein-2 (SGP-2). Pellets containing 100 μg estradiol-17β (E₂) were implanted into ovariectomized mice and removed four days later. Apoptotic indices (percentage of apoptotic cells) of both luminal and glandular epithelia increased after E₂ pellets were removed, but administration of progesterone (P), 5-dihydrotestosterone (DHT), or continued implantation of E₂ pellets suppressed this increase. Levels of mRNAs of TGF-β1, -β2, and -β3, and SGP-2 did not increase after estrogen deprivation. However, estrogen deprivation caused a gradual increase in the level of TGF-β type II receptor mRNA, and its level increased about six-fold six days later. Moreover, E₂, P, and DHT markedly decreased the level of TGF-β type II receptor mRNA. In situ hybridization demonstrated that mRNAs of TGF-β1, -β2, -β3 and TGF-β type II receptor were localized to the epithelium. Exogenous administration of TGF-β1 into the uterine stroma induced apoptosis in the epithelium, a finding that suggests that signals produced by TGF-βs can induce apoptosis. Therefore, the present results suggest that increased sensitivity of uterine epithelial cells to TGF-βs, as demonstrated by an increase in TGF-β type II receptor mRNA, is involved in the induction of apoptosis after estrogen deprivation, although signals produced by TGF-βs do not appear sufficient to induce apoptosis.     

Development of galactomannan-hydrolyzing activity in the micropylar endosperm tip of tomato seed prior to germination

Development of galactomannan-hydrolyzing activity, that is involved in the weakening of the mechanical restraint of the endosperm, was followed at pre-germinative stages in tomato ( Lycopersicon esculentum ) seed. Prior to germination the activity developed exclusively in the endosperm portion just adjacent to the radicle tip. In other parts of the endosperm, the activity developed only after germination occurred. Under the conditions where germination was suppressed (far-red light- or ABA-treatment). no activity was detected in the endosperm at the pre-germinative stages. Under the conditions where the inhibition of germination was alleviated (far-red + red or ABA + GA₃), the activity developed prior to germination in the endosperm part in front of the radicle tip. Thus, a clear parallel relationship was observed between germinability of the seed and the pre-germinative development of activity in the part of the endosperm portion adjacent to the radicle tip.     

Oral administration of antigen does not influence the proliferation and IFN-γ production of responsive CD8+ T cells but enables to establish T cell clones with different lymphokine production profile.

Feeding of a whole casein diet, which abolished the α_s1-casein-specific proliferation and IFN-γ productivity of CD⁴⁺ T cells, did not affect the proliferative response of CD8⁺ T cells with regard to the antigen dose response, cell dose response, kinetics of the proliferation and epitope specificity, as well as IFN-γ production. To assess the characteristics of the CD8⁺ T cells, we established α_s1-casein-specific CD8⁺ T cell clones from both casein-fed and control mice. The established clones produced different amount of IFN-γ and IL-10, and one clone derived from the casein-fed mice produced a remarkable amount of IL-10. The clones from casein-fed mice produced considerable amounts of TGF-β, while those from control mice produced only small amounts. The possible role of CD8⁺ T cells in oral tolerance is discussed. This revised version was published online in June 2006 with corrections to the Cover Date.     

Immunological characterization of a 36 kDa Fe deficiency specific peptide in barley roots

In a previous paper we reported that an acidic 36 kDa peptide is the most strongly induced peptide among several peptides induced by Fe deficiency in barley roots. In this paper, polyclonal antibodies were raised against the 36 kDa peptide. This peptide appeared in the roots of all the graminaceous species tested (barley, rye, wheat, oat, maize, sorghum and rice) in response to Fe deficiency. More of the peptide was found in the roots of graminaceous species which secrete higher amounts of mugineic acids (MAs) under Fe deficient nutrition status. Induction of the 36 kDa peptide was first observed on the third day of Fe deficiency, rising to a maximum value on the seventh day. The trend has a positive correlation with secretion of MAs during Fe deficiency. Further, resupply of Fe resulted in a decrease in peptide production on the second day, reaching a control level on the seventh day. The rate of decrease in peptide production was observed to be slower than that of MA secretion. Other nutrient stresses such as B excess, B deficiency, Cu excess, Cu deficiency, Mn excess, Mn deficiency, Zn excess and Zn deficiency induced far less of the peptide. The specific expression of the 36 kDa peptide in roots of graminaceous species under Fe deficiency suggested the positive association of the peptide with a specific Fe deficiency tolerance mechanism in graminaceous plants.     

Phylogenetic relationships of someMicrosporum andArthroderma species inferred from mitochondrial DNA analysis

Thirty-eight strains of 12Microsporum and 10Arthroderma (Nannizzia) species were investigated by analysis of mitochondrial DNA with 6 restriction enzymes, and classified into 13 genetic groups. The phylogenetic tree of the 13 groups thus established was constructed. On the tree,M. audouinii, M. langeronii, M. rivalieri, M. distortum, M. equinum, M. ferrugineum andA. otae comprise one genetic group and are suggested to be the same species.A. gypseum, A. fulvum, M. duboisii, M. ripariae, A. incurvatum, A. persicolor andA. obtusum are clustered on one of five boughs of the tree indicating their close relation.A. racemosum andA. cajetani are also closely related.     

DNA polymerases and DNA topoisomerases solubilized from nuclear matrices of regenerating rat livers

DNA topoisomerase activity together with the activities of DNA polymerase were detected in a form tightly associated with rat liver nuclear matrices. DNA polymerase activities were solubilized from the nuclear matrices of regenerating rat livers by sonic treatment followed by extraction of these activities with detergent and salt. The predominant activity was mainly α-polymerase as judged from the size determined by sucrose density gradient centrifugation. However, only β-polymerase activity was detected in the matrix of normal rat livers. DNA topoisomerase activity, detected in both regenerating and normal liver nuclear matrices, showed a molecular size of about 4 S in sucrose gradient, and was active in the presence of EDTA. These results suggest that this enzyme belongs to type I topoisomerase.     

Cloning and nucleotide sequences of the linear DNA killer plasmids from yeast.

The linear DNA killer plasmids (pGKL1 and pGKL2) isolated from a Kluyveromyces lactis killer strain are also maintained and expressed its killer character in Saccharomyces cerevisiae. After these killer plasmid DNAs isolated from S. cerevisiae were treated with alkali, four terminal fragments from each plasmid DNAs were cloned separately. Using these and other cloned DNA fragments, the terminal nucleotide sequences of pGKL2 and the complete nucleotide sequence of pGKL1 were determined. The inverted terminal repetitions of 202 bp and 182 bp were found in pGKL1 and pGKL2, respectively. The pGKL1 sequence showed an extremely high A + T content of 73.2% and it contained five large open reading frames. The largest of these open reading frame was suggested to code for a membrane-bound precursor of glycoprotein subunit of the killer toxin.     

Characterizations and constructions of reverberating networks

Consider the family $\text{G}$_n of all n neuron networks whose dynamical behaviors are described by Caianiello's neuronic equations, and also its subfamily $\text{R}$_n of all reverberating networks each of whose neuronic equations have only periodic solution (states), i.e., without having any transient states. This paper is specifically concerned with characterizations of the subfamily $\text{R}$_n. First, we show that $\text{R}$_n is contained in a subfamily $\text{S}$_n of $\text{G}$_n consisting of all self-dual networks. We introduce Chow's matrix corresponding to each network of $\text{S}$_n, using Chow parameters and some algebraic operations {$\text{2}$_α} applied to the coefficient matrix of the network in $\text{S}$_n, such as interchanges of coefficients between two neurons or changes of their signs. Then we give some necessary conditions on Chow's matrix under which any network in $\text{S}$_n belong to $\text{R}$_n, and a necessary and sufficient condition on the coefficient matrix. We also discuss relations between Chow's matrix and the maximum period of reverberations. In particular, it is shown that Chow's matrix of a network in $\text{R}$_n is symmetric if and only if the maximum period of reverberations is less than three. By virtue of these results, we propose two methods of construction of networks in $\text{R}$_n. The first method is an inductive construction. The second is based on the algebraic operations.     

Detection and mapping of six miniF-encoded proteins by cloning analysis of dissected miniF segments

Summary Various DNA subfragments were derived from miniF DNA by complete or partial PstI cleavage, and cloned in the plasmid vectors pBR322 or dv1. The recombinant plasmids obtained were introduced into an Escherichia coli minicell-producing strain, and the plasmid-coded proteins were radiolabeled and analyzed by gel electrophoresis. Six miniF-encoded proteins, larger than 11 000 daltons, were detected and their coding regions were mapped on the F plasmid genome. Three of them were assigned by taking into account the known nucleotide sequences (Murotsu et al. 1981; K. Yoshioka, personal communication). The coding directions of some proteins were determined by inserting the lac promotor into one of the recombinant plasmids and analyzing the increase in production of the proteins. The coding direction of the five proteins analyzed so far was uniform. Comparison of these results with a functional map of miniF suggested possible roles of the proteins.