Pattern formation in the epithelium of the oviduct of Japanese quail

Cellular patterns of the oviduct epithelium from the Japanese quail were examined during maturation. The epithelium of a juvenile bird showed a jigsaw puzzle pattern consisting of a single, undifferentiated cell type. At the start of maturation, cells were rearranged into a pattern in which the length of boundaries between goblet type gland (G-) cells and ciliated (C-) cells (G-C boundaries) were maximized. At this stage, the surface area of G-cells was much smaller, but G-cells are more than 2 times more numerous than C-cells. Cells than gradually rearranged themselves into the checkerboard pattern through an increase in the proportion of C-cells and enlargement of the G-cells. At all times of maturation, the length of G-C boundaries was maximized. These observations strongly support the theory that the cellular pattern of the quail oviduct epithelium is spontaneously constructed by maximizing the length of boundaries between two different types of cells owing to the fact that theirs is the greatest adhesion capacity (Yamanaka and Honda, 1990).     

Alterations in histones of the liver and oviduct of Japanese quail during aging

Age-related changes occur in histones of the liver and oviduct of the female quail. In the liver an extra histone band, named HCX, between H2A and H4, is observed that increases with age. In the oviduct, a large complex of histones is seen which is tissue-specific. This complex declines with increasing age. The changes in the histones of the oviduct of adult and old birds in response to estradiol and progesterone are age-related. In the adult, the histone-complex increases after administration of either one of the hormones. In old birds, however, it is seen only after progesterone administration. Thus, the alterations in histones in the birds are not only tissue- and age-related, but also vary in response to steroid hormones.     

Cytochalasin D inhibits basal body migration and ciliary elongation in quail oviduct epithelium

Summary The effects of cytochalasin D (CD) were studied by scanning (SEM) and transmission (TEM) electron-microscopic examination at different stages of ciliary differentiation in epithelial cells of quail oviduct. Immature quails were prestimulated by estradiol benzoate injections to induce ciliogenesis in the undifferentiated oviduct. After 24 h of CD culture, SEM study revealed inhibition of ciliogenesis and dilation of the apex of non-ciliated cells. TEM study showed that 2 h of CD treatment produced dilation of lateral intercellular spaces, after 6 h of treatment, this resulted in intracellular macrovacuolation. Vacuoles were surrounded by aggregates of dense felt-like material. CD also induced the disappearance of microvilli, and rounding of the apical surface of undifferentiated cells and those blocked in ciliogenesis. Centriologenesis was not inhibited by CD; basal bodies assembled in generative complexes in the supranuclear region after 24 h of treatment. However, the migration of mature basal bodies towards the apical surface was impaired. Instead, they anchored onto the membrane of intracellular vacuoles; growth of cilia was induced in the vacuole lumen. Cilium elongation was disturbed, giving abnormally short cilia with a dilated tip; microtubules failed to organize correctly.     

Studies on the substrate specificity of neutral alpha-mannosidase purified from Japanese quail oviduct by using sugar chains from glycoproteins.

The substrate specificity of neutral alpha-mannosidase purified from Japanese quail oviduct [Oku, H., Hase, S., & Ikenaka, T. (1991) J. Biochem. 110, 29-34] was analyzed by using 21 oligomannose-type sugar chains. The enzyme activated with Co2+ hydrolyzed the Man alpha 1-3 and Man alpha 1-6 bonds from the non-reducing termini of Man alpha 1-6(Man alpha 1-3)Man alpha 1-6(Man alpha 1-3)Man beta 1-4GlcNAc beta 1-4GlcNAc (M5A), but hardly hydrolyzed the Man alpha 1-2 bonds of Man9GlcNAc2. The hydrolysis rate decreased as the reducing end of substrates became more bulky: the hydrolysis rate for the pyridylamino (PA) derivative of M5A as to that of M5A was 0.8; the values for M5A-Asn and Taka-amylase A having a M5A sugar chain being 0.5 and 0.04, respectively. The end product was Man beta 1-4GlcNAc2. For the substrates with the GlcNAc structure at their reducing ends (Man5GlcNAc, Man6GlcNAc and Man9GlcNAc), the hydrolysis rate was remarkably increased: Man5GlcNAc was hydrolyzed 16 times faster than M5A, and Man2GlcNAc 40 times faster than Man9GlcNAc2. The enzyme did not hydrolyze Man alpha 1-2 residue(s) linked to Man alpha 1-3Man beta 1-4GlcNAc. The end products were as follows: [formula; see text] These results suggest that oligomannose-type sugar chains with the GlcNAc structure at their reducing ends seem to be native substrates for neutral alpha-mannosidase and the enzyme seems to hydrolyze endo-beta-N-acetylgucosaminidase digests of oligomannose-type sugar chains in the cytosol.     

Purification and characterization of neutral alpha-mannosidase that is activated by Co2+ from Japanese quail oviduct

An alpha-mannosidase was purified from the magnum section of Japanese quail oviduct by ammonium sulfate precipitation, DEAE-Sephacel chromatography, Sephacryl S-300 chromatography, mannan-Sepharose 4B chromatography, and hydroxyapatite chromatography. The purified alpha-mannosidase (referred to as neutral alpha-mannosidase) showed a single band on polyacrylamide gel with or without sodium dodecyl sulfate. Its molecular weight was found to be 330,000 by gel chromatography. Neutral alpha-mannosidase hydrolyzed p-nitrophenyl alpha-D-mannopyranoside and the pyridylamino derivative of Man alpha 1-6(Man alpha 1-3)Man alpha 1-6(Man alpha 1-3)Man beta 1-4GlcNAc beta 1-4GlcNAc (Km value was 3 mM). Mannosyl alpha 1-2 linkages in the pyridylamino derivative of Man alpha 1-2 Man alpha 1-6(Man alpha 1-2Man alpha 1-3)Man alpha 1-6(Man alpha 1-2Man alpha 1-2Man alpha 1-3)Man beta 1-4GlcNAc beta 1-4GlcNAc were hardly hydrolyzed. Its optimum pH was found to be 7.0. The activity of the enzyme was activated by CO2+, and was potently inhibited by Cu2+, Hg2+, swainsonine, and 1-deoxymannojirimycin.     

Ovarian responses and serum LH levels after retraction or removal of the oviduct in Japanese quail

The effects of oviduct removal, oviduct displacement or sham-operation were studied in Japanese quail (Coturnix coturnix japonica). No significant differences were observed between the treatments for body weight, number of follicles larger than or equal to 6 mm diam., or number of ruptured follicles. Retraction or removal of the oviduct resulted in similar significant increases (P less than 0.05) in ovarian weight, diameter of the largest follicle, and serum LH levels when compared with the controls. Injection of yolk into normal hens did not cause any change. It is suggested that the oviduct normally exerts an inhibitory control on ovary growth without appreciable effect on ovulation rate.     

Subcellular aging markers of retinal pigment epithelium in Japanese quail Coturnix japonica

Age-related changes of retinal pigment epithelium of the Japanese quail, which at present is a promising experimental model of accelerated aging, were studied by electron microscopy using morphometric analysis. It was established that, along with accumulation of lipofuscin granules and ultrastructural changes of the Bruch’s membrane, changes in the shape of nuclei and mitochondria (increase in the portion of ring-shaped and dumbbell-like mitochondria), decrease in the amount of myeloid bodies, and disorganization of basal infoldings are also aging markers of retinal pigment epithelium.     

Poly(A) polymerase in quail oviduct. Changes during estrogen induction.

A nuclear poly(A) polymerase has been isolated from oviducts of immature quails. It could be purified 4300-fold. The enzyme depends specifically on ATP as substrate and requires Mg2+. The most effective primer for the enzyme is a polynucleotide, isolated from oviduct tissue. A poly(A) sequence to a maximum of 60 AMP residues is covalently linked per primer molecule. The poly(A)-rich product of the enzymatic reaction can be annealed to oligo(dT)-cellulose. The purest fraction does not contain any detectable poly(A)-degrading enzyme activity. Only very low activities of RNA polymerase are present. The poly(A polymerase activity in the assay with ATP is reduced by the ATP analogue, beta, lambda-ATP-methylene-diphosphonate. Both K-m and V are lowered. The ATP analogue is incorporated to a smaller extent into the poly(A) sequence, synthesized by the enzyme. Several other analogues of adenine, adenine nucleosides and adenine nucleotides are without effect on the enzymatic reaction. By these properties poly(A) polymerase can be distinguished from RNA polymerases form I and form II, isolated from the same tissue. Actinomycin D and alpha-amanitin failed to inhibit poly(A) polymerase activity. The activity of poly(A) polymerase has been determined during primary stimulation with the estrogen analogue diethylstilbestrol (daily injection for 5 days), after withdrawal of the hormone for 17 days and after secondary stimulation with the hormone analogue. The enzyme activity does not change during primary stimulation, withdrawal of the hormone or secondary stimulation. However the activity of a poly(A) degrading enzyme, localized in the nucleus, is reduced in oviducts from hormone-treated quails.     

[Ciliogenesis in the mucous cells of the quail oviduct. I. Ultrastructural study in the laying quail]

The luminal epithelium of the oviduct (magnum) of laying quails is composed of ciliated cells and mucous cells. Ciliogenesis was observed in some of the mucous cells. Both centrioles of the diplosome migrate to the top of the cell, and one of them induces the formation of a rudimentary cilium. In some of the other cells, that are filled with mucous granules, the formation of basal bodies by an acentriolar pathway was observed. In these cells, numerous, dense fibrous masses are associated with the forming face of the Golgi apparatus. In the Golgi zone, generative complexes composed of a deuterosome and some forming procentrioles were found. Cilia develop from completed basal bodies. During ciliogenesis, the Golgi apparatus is disorganized, and generally the production of mucous granules is arrested. The nucleus is also modified: it becomes larger and the chromatin is dispersed. It is assumed that mucous cells are able to be transformed into ciliated cells in the oviduct of laying quails.     

Modulation of quail oviduct adenylate cyclase activity by estradiol and progesterone

Oviduct adenylate cyclase activity of the quail was measured by radiochemical analysis following different hormonal treatments. A single injection of estradiol benzoate (EB) to immature female quails resulted in a prereplicative surge of adenylate cyclase activity. A second surge of enzyme activity was observed during the proliferative phase induced by EB. Estradiol-17 alpha, estrone, estriol and testosterone were ineffective. Tamoxifen completely inhibits the growth-promoting effect of EB and the second surge of adenylate cyclase activity but does not inhibit the prereplicative increase of enzyme activity. This prereplicative increase of adenylate cyclase activity was also observed, even in the absence of increased plasma estradiol, when estradiol-17 beta (E2) was perfused through the hepatic portal vein. Moreover, E2 had no effect on enzyme activity when added directly to the oviduct homogenate preparation, at concentrations ranging from 10(-9) to 10(-7) M. In response to progesterone injection, oviduct adenylate cyclase activity followed a different pattern, beginning its increase after 3 h and remaining elevated up to 24 h. The activation by estradiol was independent of the presence of guanylylimidodiphosphate. Moreover, the enzyme was more sensitive to forskolin at submaximal concentration in estradiol treated birds than in control. These results demonstrate that transient activation of adenylate cyclase at the early stages of the action of estradiol does not occur through the classic nuclear receptor-gene activation pathway or a membrane receptor mediated process, but involves an indirect pathway, yet to be defined.     

Endocytosis in the epithelium of the mouse oviduct

We studied the pathway of serum protein transport into the lumen of the mouse oviduct by localizing several tracer proteins in the oviduct after intravenous injection on days 1, 5, and 11 of pregnancy. Fluorescent proteins were observed in the lamina propria and in vesicles in the lumenal epithelial cells mainly in the preampulla segment on days 5 and 11 of pregnancy. In the isthmus, there was much less fluorescence in the lamina propria and no fluorescent vesicles in lumenal epithelial cells. This is similar to previous observations on day 1 and indicates that the uptake of serum proteins into lumenal epithelial cells in the preampulla is not limited to the time when embryos are present in the oviductal lumen. Horseradish peroxidase (HRP) was present in the lamina propria of the preampulla on days 1 and 5, but direct tracer movement into the oviductal lumen was blocked by the epithelial junctional complexes. Within the epithelial cells, HRP was localized in endocytic vesicles along the basolateral membrane, multivesicular bodies (mvb), elongated dense bodies below the nucleus (bdb), and many small vesicles near the apical surface of the cells. Ferritin was also used as a tracer and was observed in the same locations as HRP. Acid phosphatase in the epithelial cells of the preampulla on day 1 was localized in mvb and bdb, indicating that these structures are lysosomes. It appeared that HRP and ferritin followed two pathways after basolateral endocytosis by the epithelial cells in the preampulla: 1) they were transported to apical vesicles that may release their contents into the oviductal lumen, or 2) they were transported to lysosomes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Reverse banding of Japanese quail microchromosomes.

Cells isolated from adult and fetal rat liver and ascites hepatoma were separated into distinct populations by velocity sedimentation at unit gravity. Normal adult liver ceils sediment with modal velocities ranging from 5 to 50 mm/h. Volume analysis using a Coulter-type counter demonstrated that the separation was based primarily on cell size. Appreciable differences were observed in the sedimentation velocity distribution of cells isolated from different normal lobes or regenerating liver. Most fetal rat liver cells sediment with velocities inferior to 12 mm/h. Ascites (Novikoff) hepatoma cells present a velocity distribution more similar to that of fetal than to normal adult liver cells. The results are discussed in terms of cell-size changes associated with liver maturation, regeneration or transformation.     

A first-generation microsatellite linkage map of the Japanese quail

A linkage map of the Japanese quail (Coturnix japonica) genome was constructed based upon segregation analysis of 72 microsatellite loci in 433 F(2) progeny of 10 half-sib families obtained from a cross between two quail lines of different genetic origins. One line was selected for long duration of tonic immobility, a behavioural trait related to fearfulness, while the other was selected based on early egg production. Fifty-eight of the markers were resolved into 12 autosomal linkage groups and a Z chromosome-specific linkage group, while the remaining 14 markers were unlinked. The linkage groups range from 8 cM (two markers) to 206 cM (16 markers) and cover a total map distance of 576 cM with an average spacing of 10 cM between loci. Through comparative mapping with chicken (Gallus gallus) using orthologous markers, we were able to assign linkage groups CJA01, CJA02, CJA05, CJA06, CJA14 and CJA27 to chromosomes. This map, which is the first in quail based solely on microsatellites, is a major step towards the development of a quality molecular genetic map for this valuable species. It will provide an important framework for further genetic mapping and the identification of quantitative trait loci controlling egg production and fear-related behavioural traits in quail.     

Growth inhibition and the regulation of cyclic AMP by the triphenylethylene anti-estrogen tamoxifen in the quail oviduct.

The aim of the present study was to investigate the regulation of cAMP by tamoxifen in quail oviduct. A single injection of tamoxifen to immature female quails induced a transient activation of adenylate cyclase. Enzyme activity began to increase 3 h after the injection, peaked at 6 h and then dropped to control level at 12 h. The same time-response curves were observed following the injection of estradiol benzoate or estradiol benzoate + tamoxifen. Moreover, adenylcyclase exhibited the same sensitivity to exogenous activators (guanylylimidodiphosphate and forskolin) in the different treated groups. Phosphodiesterase activity was left unchanged during the prereplicative period and cAMP concentration was significantly increased at 6 h (+ 44.3%). Then, cAMP concentration continued to increase (+ 73.8% at 24 h) while cAMP phosphodiesterase and adenylcyclase activities remained at control levels. Injected concurrently with estradiol benzoate, tamoxifen completely inhibited the growth promoting effect of estradiol. Tamoxifen also inhibited the activation of adenylcyclase and cAMP phosphodiesterase induced by the hormone alone during the proliferative phase of the tissue. Moreover, the combined treatment led to a sustained elevation of cAMP in the oviduct, whereas estradiol benzoate alone decreased the level of cAMP. These results and those of our previous studies showing a significant correlation between the growth inhibitory potency of triphenylethylene derivatives in vivo and their efficiency to inhibit calmodulin-dependent cAMP phosphodiesterase in vitro, strongly suggest that the differential regulation of cAMP levels by estradiol and tamoxifen is essential for the growth promoting or growth inhibiting activities of these molecules.