Three-dimensional cell culture using CD9-positive cells isolated from marginal cell layer of intermediate lobe of rats sustains in vivo-like primary niche environment.

The adenohypophysis is composed of the anterior and intermediate lobes (AL and IL, respectively), and secretes hormones that play an important role in reproduction. CD9- and SOX2-double (CD9/SOX2) positive cells located in the marginal cell layer (MCL) facing the Rathke's cleft in the AL and IL form the primary stem cell niche in the adult adenohypophysis of rats. In this study, we successfully obtained 3-dimensional (3D) cell aggregates that closely resembled the primary niche of MCL in vivo.

Primary Cilia are Required for Cell-Type Determination and Angiogenesis in Pituitary Development.

The functional maturation of the pituitary gland requires adequate cell differentiation and vascular network formation. Although spatiotemporal signaling and transcription factors are known to govern pituitary development, the involvement of primary cilia, nonmoving hair-like organelles, remains unclear. In this study, we uncovered the contribution of primary cilia to cell-type determination and vascular network formation during pituitary development.

Expression of Retinaldehyde Dehydrogenases in the Pituitary Glands of Fetus and Adult Mice.

Retinoic acid (RA) plays a critical role in cell growth and tissue development. RA is synthesized from retinoids through oxidation processes by the retinaldehyde dehydrogenase (Raldh) family. However, the expression of during pituitary development and the identification of -expressing cells in the adult pituitary have not been fully elucidated.

Positive regulation of Hedgehog signaling via phosphorylation of GLI2/GLI3 by DYRK2 kinase.

Hedgehog (Hh) signaling, an evolutionarily conserved pathway, plays an essential role in development and tumorigenesis, making it a promising drug target. Multiple negative regulators are known to govern Hh signaling; however, how activated Smoothened (SMO) participates in the activation of downstream GLI2 and GLI3 remains unclear. Herein, we identified the ciliary kinase DYRK2 as a positive regulator of the GLI2 and GLI3 transcription factors for Hh signaling.

Paracrine and endocrine pathways of natriuretic peptides assessed by ligand-receptor mapping in the Japanese eel brain.

The natriuretic peptide (NP) family consists of cardiac NPs (ANP, BNP, and VNP) and brain NPs (CNPs) in teleosts. In addition to CNP1-4, a paralogue of CNP4 (named CNP4b) was recently discovered in basal teleosts including Japanese eel. Mammals have lost most Cnps during the evolution, but teleost cnps were conserved and diversified, suggesting that CNPs are important hormones for maintaining brain functions in teleost.

Fluctuation of CD9/SOX2-positive cell populations during the turnover of GH- and TSH-producing cells in the adult anterior pituitary gland.

The adenohypophysis is comprised of the anterior and intermediate lobes (AL and IL, respectively). Cluster of differentiation 9 (CD9)- and sex-determining region Y-box 2 (SOX2)-positive cells are stem/progenitor hormone-producing cells in the AL. They are located in the marginal cell layer (MCL) facing Rathke's cleft between the AL and IL (primary niche) and the parenchyma of the AL (secondary niche).

Subcellular localization of Na/K-ATPase isoforms resolved by in situ hybridization chain reaction in the gill of chum salmon at freshwater and seawater.

The Na/K-ATPase (NKA) α1-isoforms were examined by in situ hybridization chain reaction (ISHCR) using short hairpin DNAs, and we showed triple staining of NKA α1a, α1b, and α1c transcripts in the gill of chum salmon acclimated to freshwater (FW) and seawater (SW). The NKA α1-isoforms have closely resembled nucleotide sequences, which could not be differentiated by conventional in situ hybridization. The ISHCR uses a split probe strategy to allow specific hybridization using regular oligo DNA, resulting in high specificity at low cost.

Behavioural osmoregulation during land invasion in fish: Prandial drinking and wetting of the dry skin.

Osmoregulatory behaviours should have evolutionarily modified for terrestrialisation of vertebrates. In mammals, sensations of buccal food and drying have immediate effects on postprandial thirst to prevent future systemic dehydration, and is thereby considered to be 'anticipatory thirst'. However, it remains unclear whether such an anticipatory response has been acquired in the non-tetrapod lineage.

Differentiation of stem progenitor CD9/SOX2-positive cells is promoted with increased prolactin-producing and endothelial cells in the pituitary.

Sex-determining region Y-box 2 (SOX2)-positive cells are stem/progenitor cells in the adenohypophysis, comprising the anterior and intermediate lobes (AL and IL, respectively). The cells are located in the marginal cell layer (MCL) facing Rathke's cleft (primary niche) and the parenchyma of the AL (secondary niche). We previously demonstrated in vitro that the tetraspanin superfamily CD9 and SOX2 double-positive (CD9/SOX2-positive) cells in the IL-side MCL migrate to the AL side and differentiate into hormone-producing and endothelial cells in the AL parenchyma.

The multiciliated cells in Rathke's cleft express CYP26A1 and respond to retinoic acid in the pituitary.

The adenohypophysis consists of the anterior and intermediate lobes (AL and IL). The marginal cell layer (MCL), including the ventral region of the IL and the dorsal region of the AL lining the Rathke's cleft, acts as the primary stem/progenitor cell niches in adult adenohypophysis. The cells of the MCL on the IL side consisted of cluster of differentiation 9 (CD9)-positive stem/progenitor cells with or without motile cilia.

Gene duplication of C-type natriuretic peptide-4 (CNP4) in teleost lineage elicits subfunctionalization of ancestral CNP.

The diversified natriuretic peptide (NP) family, consisting of four CNPs (CNP1-4), ANP, BNP, and VNP, has been identified in the eel. Here, we successfully cloned additional cnp genes from the brain of eel (a basal teleost) and zebrafish (a later branching teleost). The genes were identified as paralogues of cnp4 generated by the third round of whole genome duplication (3R) in the teleost lineage, thereby being named eel cnp4b and zebrafish cnp4-like, respectively.

Molecular mechanisms underlying guanylin-induced transcellular Cl secretion into the intestinal lumen of seawater-acclimated eels.

Guanylin (GN) stimulates Cl secretion into the intestinal lumen of seawater-acclimated eels, but the molecular mechanisms of transepithelial Cl transport are still unknown. In Ussing chamber experiments, we confirmed that mucosal application of eel GN reversed intestinal serosa-negative potential difference, indicating Cl secretion. Serosal application of DNDS or mucosal application of DPC inhibited the GN effect, but serosal application of bumetanide had no effect.

CD9-positive cells in the intermediate lobe of the pituitary gland are important supplier for prolactin-producing cells in the anterior lobe.

A supply of hormone-producing cells from stem/progenitor cells is critical to sustain the endocrine activity of the pituitary gland. In the adenohypophysis composing the anterior and intermediate lobe (AL and IL, respectively), stem/progenitor cells expressing sex-determining region Y-box 2 (SOX2) and S100β are located in the marginal cell layer (MCL) facing Rathke's cleft (primary niche) and the parenchyma of the AL (secondary niche). Our previous studies using mice and rats indicated that the tetraspanin superfamily CD9 and CD81 are expressed in S100β/SOX2-positive cells of primary and secondary niches (named CD9/CD81/S100β/SOX2-positive cell), and the cells located in the AL-side niches exhibit plasticity and multipotency.

Cluster of differentiation (CD) 9-positive mouse pituitary cells are adult stem/progenitor cells.

SOX2-positive cells are stem/progenitor cells that supply hormone-producing cells; they are found in the anterior lobe of the rodent pituitary gland. However, they are likely composed of several subpopulations. In rats, a SOX2-positive cell populations can be distinguished by the presence of S100β.

Expression and functions of cluster of differentiation 9 and 81 in rat mammary epithelial cells.

Cluster of differentiation (CD) 9 and CD81 are closely-related members of the tetraspanin family that consist of four-transmembrane domain proteins. Cd9 and Cd81 are highly expressed in breast cancer cells; however, their expression in healthy mammary glands is unclear. In this study, we performed quantitative real-time PCR to analyze the expression levels of Cd9 and Cd81.

Aldolase C is a novel molecular marker for folliculo-stellate cells in rodent pituitary.

The anterior pituitary gland is composed of five types of hormone-producing cells and folliculo-stellate cells. Folliculo-stellate cells do not produce anterior pituitary hormones but they are thought to play important roles as stem cells, phagocytes, or supporting cells of hormone-producing cells in the anterior pituitary. S100β protein has been used as a folliculo-stellate cell marker in some animals, including rats.

CX3CL1/CX3CR1-signalling in the CD9/S100β/SOX2-positive adult pituitary stem/progenitor cells modulates differentiation into endothelial cells.

Approximately 8% of CD9-, S100β- and SOX2-triple positive (CD9/S100β/SOX2-positive) stem/progenitor cells in the anterior lobe of the rat pituitary gland have previously been shown to differentiate into endothelial cells in vitro, suggesting that they play a role in vascularisation as tissue-resident vascular precursor cells. In the present study, we focused on chemokine ligands to further characterise the CD9/S100β/SOX2-positive cells and found that they distinctively express CX3C chemokine ligand 1 (Cx3cl1). Immunohistochemical analysis of the anterior lobe showed that CX3CL1-positive cells comprised 7.

Seawater transfer down-regulates C-type natriuretic peptide-3 expression in prolactin-producing cells of Japanese eel: Negative correlation with plasma chloride concentration.

In euryhaline fishes, atrial and B-type natriuretic peptides are important hormones in hypo-osmoregulation, whereas osmoregulatory functions of C-type natriuretic peptides (CNPs) remain to be investigated. Although four CNP isoforms (CNP1-4) are mainly expressed in the brain, multiorgan expression of CNP3 was found in euryhaline Japanese eel, Anguilla japonica. Here we identified the CNP3-expressing cells and examined their response to osmotic stress in eel.

Histological differentiation of mucus cell subtypes suggests functional compartmentation in the eel esophagus.

We investigated the morphological and histological changes in eel esophagus during the course of freshwater (FW) to seawater (SW) transfer and identified multiple types of mucus cells from tissues that were fixed using Carnoy's solution to retain the mucus structure. The FW esophageal epithelium is stratified and composed of superficial cells, mucus cells, club cells (exocrine cells with a large vacuole), and basal cells. Two types of periodic acid-Schiff (PAS)-positive mucus cells were identified, and they can be further distinguished by the periodic acid-thionin Schiff/KOH/PAS (PAT) method, indicating that C7/9- and C8-sialic acids were produced.

Identification of TGFβ-induced proteins in non-endocrine mouse pituitary cell line TtT/GF by SILAC-assisted quantitative mass spectrometry.

TtT/GF is a mouse cell line derived from a thyrotropic pituitary tumor and has been used as a model of folliculostellate cells. Our previous microarray data indicate that TtT/GF possesses some properties of endothelial cells, pericytes and stem/progenitor cells, along with folliculostellate cells, suggesting its plasticity. We also found that transforming growth factor beta (TGFβ) alters cell motility, increases pericyte marker transcripts and attenuates endothelial cell and stem/progenitor cell markers in TtT/GF cells.

Immunohistochemical Study of the Laminin α5 Chain and Its Specific Receptor, Basal Cell Adhesion Molecule (BCAM), in both Fetal and Adult Rat Pituitary Glands.

Laminin, a major basement membrane protein, comprises three subunit chains: α, β, and γ chains. Among these chains, only the laminin α chain is capable of signaling via laminin receptors. Although laminin isoforms containing the α5 chain were reported to be the first laminin produced during rat anterior pituitary gland development, the functions of these isoforms are unknown.

Isolation and characterisation of CD9-positive pituitary adult stem/progenitor cells in rats.

S100β protein and SOX2-double positive (S100β/SOX2-positive) cells have been suggested to be adult pituitary stem/progenitor cells exhibiting plasticity and multipotency. The aim of the present study was to isolate S100β/SOX2-positive cells from the adult anterior lobes of rats using a specific antibody against a novel membrane marker and to study their characteristics in vitro. We found that cluster of differentiation (CD) 9 is expressed in the majority of adult rat S100β/SOX2-positive cells, and we succeeded in isolating CD9-positive cells using an anti-CD9 antibody with a pluriBead-cascade cell isolation system.

TGFβ signaling reinforces pericyte properties of the non-endocrine mouse pituitary cell line TtT/GF.

The non-endocrine TtT/GF mouse pituitary cell line was derived from radiothyroidectomy-induced pituitary adenoma. In addition to morphological characteristics, because the cells are S100β-positive, they have been accepted as a model of folliculostellate cells. However, our recent microarray analysis indicated that, in contrast to folliculostellate cells, TtT/GF cells might not be terminally differentiated, as they share some properties with stem/progenitor cells, vascular endothelial cells and pericytes.

A sodium binding system alleviates acute salt stress during seawater acclimation in eels.

Background: Teleosts transiting from freshwater (FW) to seawater (SW) environments face an immediate osmotic stress from ion influxes and water loss, but some euryhaline species such as eels can maintain a stable plasma osmolality during early SW exposure. The time course changes in the gene expression, protein abundance, and localization of key ion transporters suggested that the reversal of the ion transport systems was gradual, and we investigate how eels utilize a Na-binding strategy to slow down the ion invasion and complement the transporter-mediated osmoregulation.

Results: Using an electron probe micro-analyzer, we localized bound Na in various eel tissues in response to SW transfer, suggesting that the Na-binding molecules were produced to sequester excess ionic Na to negate its osmotic potential, thus preventing acute cellular dehydration.

Fibromodulin Expression in Folliculostellate Cells and Pericytes Is Promoted by TGFβ Signaling in Rat Anterior Pituitary Gland.

Fibromodulin belongs to the family of small leucine-rich proteoglycans (SLRPs), an active component of extracellular matrix. It directly binds collagens to promote fibrillogenesis and also binds transforming growth factor-beta (TGFβ) to antagonize its actions. Our previous studies of rat anterior pituitary gland revealed that fibromodulin is expressed in folliculostellate cells and pericytes.