Tissue flow regulates planar cell polarity independently of the Frizzled core pathway.

Planar cell polarity (PCP) regulates the orientation of external structures. A core group of proteins that includes Frizzled forms the heart of the PCP regulatory system. Other PCP mechanisms that are independent of the core group likely exist, but their underlying mechanisms are elusive.

Preservation of collagen in the soft tissues of frozen mammoths.

We investigated the characteristics of extracellular matrix (ECM) in the soft tissue of two frozen baby woolly mammoths (Mammuthus primigenius) that died and were buried in Siberian permafrost approximately 40,000 years ago. Morphological and biochemical analyses of mammoth lung and liver demonstrated that those soft tissues were preserved at the gross anatomical and histological levels. The ultrastructure of ECM components, namely a fibrillar structure with a collagen-characteristic pattern of cross-striation, was clearly visible with transmission and scanning electron microscopy.

Measurements of radiocesium in animals, plants and fungi in Svalbard after the Fukushima Daiichi nuclear power plant disaster.

An earthquake struck the eastern part of Japan on March 11, 2011. The Fukushima Daiichi nuclear power plant was severely damaged by the earthquake and subsequent tsunami, leading to the emission of large amounts of radioactive pollutants, including Cs and Cs, into the environment. From August 23 to September 1 in 2011, and from August 27 to September 4 in 2013, we collected samples of animals, plants, fungi and lichens from Svalbard, Norway and measured the radioactivity of Cs and Cs contained in the samples.

Histopathological and electron microscopic study in dogs with patellar luxation and skin hyperextensibility.

Patellar luxation is abnormal displacement of the patella from the femoral trochlear groove. It is seen primarily in small breed dogs and causes pain and limited mobility of the stifle joint. This study aimed to investigate the relationship among patellar luxation, skin extension, and skin collagen fibril diameter.

The stellate cell system (vitamin A-storing cell system).

Past, present, and future research into hepatic stellate cells (HSCs, also called vitamin A-storing cells, lipocytes, interstitial cells, fat-storing cells, or Ito cells) are summarized and discussed in this review. Kupffer discovered black-stained cells in the liver using the gold chloride method and named them stellate cells (Sternzellen in German) in 1876. Wake rediscovered the cells in 1971 using the same gold chloride method and various modern histological techniques including electron microscopy.

The coordinated action of lecithin:retinol acyltransferase and cellular retinol-binding proteins for regulation of vitamin A esterification.

Vitamin A is a fat-soluble vitamin required for many physiological functions. The intracellular transport of vitamin A is assisted by proteins called cellular retinol-binding proteins (CRBP I/II). The absorption, storage and usage of vitamin A are regulated by a protein called lecithin:retinol acyltransferase (LRAT), a retinol-related enzyme that transfers an acyl group derived from an sn-1 position of phosphatidylcholine to retinol.

Massive bowel resection upregulates the intestinal mRNA expression levels of cellular retinol-binding protein II and apolipoprotein A-IV and alters the intestinal vitamin A status in rats.

Short bowel (SB) syndrome causes the malabsorption of various nutrients. Among these, vitamin A is important for a number of physiological activities. Vitamin A is absorbed by epithelial cells of the small intestine and is discharged into the lymphatic vessels as a component of chylomicrons and is delivered to the liver.

Morphological study of the accommodative apparatus in the monkey eye.

For more than a century there has been debate concerning the mechanism of accommodation--whether the lens capsule or lens material itself determines the functional relationship between ciliary muscle contractility and lens deformation during refractive adaptation. This morphological study in monkey eyes investigates the composition and distribution of several connective tissue components in the accommodative apparatus relaying muscle force to lens organization. Elastin distributes on the marginal surface of the ciliary process.

Dachsous-dependent asymmetric localization of spiny-legs determines planar cell polarity orientation in Drosophila.

In Drosophila, planar cell polarity (PCP) molecules such as Dachsous (Ds) may function as global directional cues directing the asymmetrical localization of PCP core proteins such as Frizzled (Fz). However, the relationship between Ds asymmetry and Fz localization in the eye is opposite to that in the wing, thereby causing controversy regarding how these two systems are connected. Here, we show that this relationship is determined by the ratio of two Prickle (Pk) isoforms, Pk and Spiny-legs (Sple).

Spatial and temporal expression of RA70/Scap2 in the developing neural tube.

Src kinase-associated phosphoprotein 2 (Ra70/scap2), which was originally isolated as a retinoic acid (RA)-induced gene, associates with molecules that modulate integrin-survival signals. Although RA is essential for vertebrate organogenesis in the posterior region, little is known about the biological role of RA70/Scap2 during development. In the present study, we demonstrate that Ra70/scap2 mRNA is temporally expressed during the RA-induced neuronal differentiation of P19 embryonic carcinoma cells.

Differential increases in the expression of intermediate filament proteins and concomitant morphological changes of transdifferentiating rat hepatic stellate cells observed in vitro.

The primary function of hepatic stellate cells (HSCs) is the storage of vitamin A. However, they are also responsible for liver fibrosis and are therapeutic targets for treatment of liver cirrhosis. Among the many molecular markers that define quiescent or activated states of HSCs, the characteristics of type III intermediate filaments are of particular interest.

Uptake and storage of vitamin A as lipid droplets in the cytoplasm of cells in the lamina propria mucosae of the rat intestine.

Vitamin A (retinyl palmitate) was injected subcutaneously or administered to rats by tube feeding. After subcutaneous injection, vitamin A was taken up and stored in cells of the lamina propria mucosae of the rat intestine. After oral administration, vitamin A was absorbed by the intestinal absorptive epithelial cells and transferred to cells of the lamina propria mucosae, where cells took up and stored the transferred vitamin A.

The role of retinoic acid receptors in activated hepatic stellate cells.

Hepatic stellate cells (HSCs), also known as Ito cells, fat-storing cells, vitamin A-storing cells or lipocytes, reside in the spaces between hepatocytes and liver sinusoids. Vitamin A storage within the HSCs is achieved through the cooperative action of two proteins, cellular retinol-binding protein (CRBP) I and lecithin:retinol acyltransferase (LRAT). After the discovery that HSCs are responsible not only for the storage of vitamin A, but also for the development of liver fibrosis and subsequent liver cirrhosis, HSCs have been considered a therapeutic target for prevention or reversal of liver fibrogenesis.

Synaptic adhesion molecules in Cadm family at the neuromuscular junction.

RA175/SynCAM1/Cadm1 (Cadm1), a member of the immunoglobulin superfamily, is a synaptic cell adhesion molecule that has a PDZ-binding motif at the C-terminal region. It promotes the formation of presynaptic terminals and induces functional synapses in the central nervous system. Cadm1-deficient (knockout [KO]) mice show behavioral abnormalities, including excessive aggression and anxiety, but do not show any symptoms of neuromuscular disorder, although neuromuscular junctions (NMJs) have structures similar to synapses.

Developmental anatomy in the zonular connection with lens capsule in macaque eye.

Morphological analyses of zonule conjugated with lens capsule were performed on the developmental change in eyes from the age of fetus to 7 years old of the rhesus macaques (Macaca fuscata). The zonule was filamentous network in late fetus. After birth, the zonular microfibrils originated from the nonpigmented epithelium of the ciliary process.

Epiplakin modifies the motility of the HeLa cells and accumulates at the outer surfaces of 3-D cell clusters.

Elimination of epiplakin (EPPK) by gene targeting in mice results in acceleration of keratinocyte migration during wound healing, suggesting that epithelial cellular EPPK may be important for the regulation of cellular motility. To study the function of EPPK, we developed EPPK knock-down (KD) and EPPK-overexpressing HeLa cells and analyzed cellular phenotypes and motility by fluorescence/differential interference contrast time-lapse microscopy and immunolocalization of actin and vimentin. Cellular motility of EPPK-KD cells was significantly elevated, but that of EPPK-overexpressing cells was obviously depressed.

Accumulation of vitamin A in the hepatic stellate cell of arctic top predators.

We performed a systematic characterization of the hepatic vitamin A storage in mammals and birds of the Svalbard Archipelago and Greenland. The liver of top predators, including polar bear, Arctic fox, bearded seal, and glaucous gull, contained about 10-20 times more vitamin A than the liver of all other arctic animals studied, as well as their genetically related continental top predators. The values are also high compared to normal human and experimental animals like mouse and rat.

Characterization of a cellular retinol-binding protein from lamprey, Lethenteron japonicum.

Lampreys are ancestral representatives of vertebrates known as jawless fish. The Japanese lamprey, Lethenteron japonicum, is a parasitic member of the lampreys known to store large amounts of vitamin A within its body. How this storage is achieved, however, is wholly unknown.

Elevated expression of transforming growth factor β3 in carbon tetrachloride-treated rat liver and involvement of retinoid signaling.

Transforming growth factor (TGF) β is a pro-fibrotic cytokine. While three isoforms (TGF-β1, 2 and 3) are known, the functional differences between them are obscure. To investigate the roles of TGF-β isoforms during liver fibrogenesis, male Wistar rats were administrated carbon tetrachloride (CCl4) subcutaneously twice a week for two months.

Induction of an incomplete autophagic response by cancer-preventive geranylgeranoic acid (GGA) in a human hepatoma-derived cell line.

GGA (geranylgeranoic acid) is a natural polyprenoic acid, derivatives of which has been shown to prevent second primary hepatoma. GGA induces mitochondria-mediated PCD (programmed cell death), which may be relevant to cancer prevention. To gain further insights into GGA-induced PCD, autophagy processes were examined in human hepatoma-derived HuH-7 cells.

Hepatic stellate cell (vitamin A-storing cell) and its relative--past, present and future.

HSCs (hepatic stellate cells) (also called vitamin A-storing cells, lipocytes, interstitial cells, fat-storing cells or Ito cells) exist in the space between parenchymal cells and liver sinusoidal endothelial cells of the hepatic lobule and store 50-80% of vitamin A in the whole body as retinyl palmitate in lipid droplets in the cytoplasm. In physiological conditions, these cells play pivotal roles in the regulation of vitamin A homoeostasis. In pathological conditions, such as hepatic fibrosis or liver cirrhosis, HSCs lose vitamin A and synthesize a large amount of extracellular matrix components including collagen, proteoglycan, glycosaminoglycan and adhesive glycoproteins.

E3 ubiquitin ligase synoviolin is involved in liver fibrogenesis.

Background And Aim: Chronic hepatic damage leads to liver fibrosis, which is characterized by the accumulation of collagen-rich extracellular matrix. However, the mechanism by which E3 ubiquitin ligase is involved in collagen synthesis in liver fibrosis is incompletely understood. This study aimed to explore the involvement of the E3 ubiquitin ligase synoviolin (Syno) in liver fibrosis.

Intracapsular organization of ciliary zonules in monkey eyes.

Ciliary zonules are responsible for changing the curvature of a lens in the dioptric focus of an eye. Present established theory is based on the relaxation of zonular superficial fasciculi affixed to the capsular surface, thereby inducing the change of anterior- and posterior lens curvature causing spontaneous liquid movement of lens material. To achieve precise focusing at any distance, a more active functional organization should exist.

Onset of apoptosis in the cystic duct during metamorphosis of a Japanese lamprey, Lethenteron reissneri.

A nonparasitic lamprey in Japan, Lethenteron reissneri, stops feeding prior to the commencement of metamorphosis. Resumption of feeding cannot take place due to major alterations in the digestive system, including loss of the gall bladder (GB) and biliary tree in the liver. This degeneration of bile ducts is considered to depend on programmed cell death or apoptosis, but molecular evidence of apoptosis remains lacking.

Retinoid storage in the egg of reptiles and birds.

Storage of retinal has been confirmed in eggs from a range of anamniotic vertebrates (teleosts and amphibians) and an ascidian, but the retinoid-storage state in eggs of oviparous amniotic vertebrates (reptiles and birds) has yet to be clarified in detail. We studied four reptilian and five avian species and found that retinal was commonly stored in their egg yolk. Furthermore, retinal was the major retinoid in reptilian eggs, with only low levels of retinol, whereas significant amounts of retinol as well as retinal were stored in avian eggs.