scholarly journals Molecular Cloning of Otoconin-22 Complementary Deoxyribonucleic Acid in the Bullfrog Endolymphatic Sac: Effect of Calcitonin on Otoconin-22 Messenger Ribonucleic Acid Levels

Endocrinology ◽  
2003 ◽  
Vol 144 (8) ◽  
pp. 3287-3296 ◽  
Author(s):  
Yuichi Yaoi ◽  
Masakazu Suzuki ◽  
Hideaki Tomura ◽  
Yuichi Sasayama ◽  
Sakae Kikuyama ◽  
...  
Keyword(s):  
Amino Acids ◽  
Calcium Carbonate ◽  
Inner Ear ◽  
Rana Catesbeiana ◽  
Endolymphatic Sac ◽  
Major Protein ◽  
Mrna Levels ◽  
Calcitonin Receptor ◽  
Messenger Ribonucleic Acid ◽  
Complementary Deoxyribonucleic Acid

Abstract Anuran amphibians have a special organ called the endolymphatic sac (ELS), containing many calcium carbonate crystals, which is believed to have a calcium storage function. The major protein of aragonitic otoconia, otoconin-22, which is considered to be involved in the formation of calcium carbonate crystals, has been purified from the saccule of the Xenopus inner ear. In this study, we cloned a cDNA encoding otoconin-22 from the cDNA library constructed for the paravertebral lime sac (PVLS) of the bullfrog, Rana catesbeiana, and sequenced it. The bullfrog otoconin-22 encoded a protein consisting of 147 amino acids, including a signal peptide of 20 amino acids. The protein had cysteine residues identical in a number and position to those conserved among the secretory phospholipase A2 family. The mRNA of bullfrog otoconin-22 was expressed in the ELS, including the PVLS and inner ear. This study also revealed the presence of calcitonin receptor-like protein in the ELS, with the putative seven-transmembrane domains of the G protein-coupled receptors. The ultimobranchialectomy induced a prominent decrease in the otoconin-22 mRNA levels of the bullfrog PVLS. Supplementation of the ultimobranchialectomized bullfrogs with synthetic salmon calcitonin elicited a significant increase in the mRNA levels of the sac. These findings suggest that calcitonin secreted from the ultimobranchial gland, regulates expression of bullfrog otoconin-22 mRNA via calcitonin receptor-like protein on the ELS, thereby stimulating the formation of calcium carbonate crystals in the lumen of the ELS.

The Role of the Endolymphatic Sac in Inner Ear Immunity

1987 ◽  
Vol 103 (5) ◽  
pp. 182-188 ◽  
Author(s):  
Shunichi Tomiyama ◽  
Jeffrey Harris
Keyword(s):  
Inner Ear ◽  
Endolymphatic Sac

Gene Transfer to the Inner Ear Following Adenoviral Vector Inoculation into the Endolymphatic Sac.

2000 ◽  
Vol 59 (1) ◽  
pp. 45-51
Author(s):  
Tatsuya Yamasoba ◽  
Masao Yagi ◽  
Mitsuya Suzuki
Keyword(s):  
Gene Transfer ◽  
Inner Ear ◽  
Adenoviral Vector ◽  
Endolymphatic Sac

scholarly journals Identification and characterization of amphibian SLC26A5 using RNA-Seq

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Zhongying Wang ◽  
Qixuan Wang ◽  
Hao Wu ◽  
Zhiwu Huang
Keyword(s):  
Amino Acid ◽  
Inner Ear ◽  
Hair Cells ◽  
Rana Catesbeiana ◽  
Site Directed Mutagenesis ◽  
Amino Acid Residues ◽  
Rna Seq ◽  
American Bullfrog ◽  
Frog Species

Abstract Background Prestin (SLC26A5) is responsible for acute sensitivity and frequency selectivity in the vertebrate auditory system. Limited knowledge of prestin is from experiments using site-directed mutagenesis or domain-swapping techniques after the amino acid residues were identified by comparing the sequence of prestin to those of its paralogs and orthologs. Frog prestin is the only representative in amphibian lineage and the studies of it were quite rare with only one species identified. Results Here we report a new coding sequence of SLC26A5 for a frog species, Rana catesbeiana (the American bullfrog). In our study, the SLC26A5 gene of Rana has been mapped, sequenced and cloned successively using RNA-Seq. We measured the nonlinear capacitance (NLC) of prestin both in the hair cells of Rana’s inner ear and HEK293T cells transfected with this new coding gene. HEK293T cells expressing Rana prestin showed electrophysiological features similar to that of hair cells from its inner ear. Comparative studies of zebrafish, chick, Rana and an ancient frog species showed that chick and zebrafish prestin lacked NLC. Ancient frog’s prestin was functionally different from Rana. Conclusions We mapped and sequenced the SLC26A5 of the Rana catesbeiana from its inner ear cDNA using RNA-Seq. The Rana SLC26A5 cDNA was 2292 bp long, encoding a polypeptide of 763 amino acid residues, with 40% identity to mammals. This new coding gene could encode a functionally active protein conferring NLC to both frog HCs and the mammalian cell line. While comparing to its orthologs, the amphibian prestin has been evolutionarily changing its function and becomes more advanced than avian and teleost prestin.

Functional Properties of the Protein Isolate and Major Fractions of Pine Nut Proteins Prepared from the Changbai Mountain in China

2014 ◽  
Vol 881-883 ◽  
pp. 766-775 ◽  
Author(s):  
Dan Wu ◽  
Wei Hong Min ◽  
Jing Sheng Liu ◽  
Li Fang ◽  
Hong Mei Li ◽  
...  
Keyword(s):  
Amino Acids ◽  
Functional Properties ◽  
Protein Solubility ◽  
Essential Amino Acids ◽  
Protein Isolate ◽  
Absorption Capacity ◽  
Changbai Mountain ◽  
Major Protein ◽  
Pine Nut ◽  
A Value

The functional properties of protein isolate and major protein fractions prepared from Changbai Mountain pine nuts were investigated. Albumin, globulin, glutelin, and protein isolates were obtained after the Osborne method and alkaline dissolution and acid precipitation, and protein contents of the fractions are 48.02%, 81.93%, 83.02%, and 89.69%, respectively. For the sulfhydryl contents, albumin is the highest, and glutelin is the lowest. In a disulphide bond, the protein isolate content is the highest with a value of 28.74 μmol/g, and the glutelin content is the lowest with the value of 13.46 μmol/g. For the four kinds of proteins, the essential amino acids in percentage of total amino acids are 31.13%, 34.22%, 30.30%, and 34.54%, respectively. The pH dependent protein solubility profile reveals that the minimum solubility is at pH 5.0, which corresponds to the isoelectric point. Protein isolate has the minimum water absorption capacity with a value of 0.59 ml/g. On the other hand, albumin has the minimum oil absorption capacity with a value of 2.11 ml/g. The emulsifying activity and stability and the foaming activity and stability increased with increasing concentration of four kinds of proteins. SDS-PAGE results showed that these four kinds of proteins have different molecules.

scholarly journals Differential Effects of Gonadotropin-Releasing Hormone (GnRH) Pulse Frequency on Gonadotropin Subunit and GnRH Receptor Messenger Ribonucleic Acid Levels in Vitro*

Endocrinology ◽  
1997 ◽  
Vol 138 (3) ◽  
pp. 1224-1231 ◽  
Author(s):  
Ursula B. Kaiser ◽  
Andrzej Jakubowiak ◽  
Anna Steinberger ◽  
William W. Chin
Keyword(s):  
Gene Expression ◽  
Messenger Rna ◽  
Pulse Frequency ◽  
Gnrh Receptor ◽  
Pituitary Cells ◽  
Mrna Levels ◽  
Subunit Gene ◽  
Differential Effects ◽  
Messenger Ribonucleic Acid

Abstract The hypothalamic hormone, GnRH, is released and transported to the anterior pituitary in a pulsatile manner, where it binds to specific high-affinity receptors and regulates gonadotropin biosynthesis and secretion. The frequency of GnRH pulses changes under various physiological conditions, and varying GnRH pulse frequencies have been shown to regulate differentially the secretion of LH and FSH and the expression of the gonadotropin α, LHβ, and FSHβ subunit genes in vivo. We demonstrate differential effects of varying GnRH pulse frequency in vitro in superfused primary monolayer cultures of rat pituitary cells. Cells were treated with 10 nm GnRH pulses for 24 h at a frequency of every 0.5, 1, 2, or 4 h. α, LHβ, and FSHβ messenger RNA (mRNA) levels were increased by GnRH at all pulse frequencies. α and LHβ mRNA levels and LH secretion were stimulated to the greatest extent at a GnRH pulse frequency of every 30 min, whereas FSHβ mRNA levels and FSH secretion were stimulated maximally at a lower GnRH pulse frequency, every 2 h. GnRH receptor (GnRHR) mRNA levels also were increased by GnRH at all pulse frequencies and were stimulated maximally at a GnRH pulse frequency of every 30 min. Similar results were obtained when the dose of each pulse of GnRH was adjusted to maintain a constant total cumulative dose of GnRH over 24 h. These data show that gonadotropin subunit gene expression is regulated differentially by varying GnRH pulse frequencies in vitro, suggesting that the differential effects of varying GnRH pulse frequencies on gonadotropin subunit gene expression occur directly at the level of the pituitary. The pattern of regulation of GnRHR mRNA levels correlated with that of α and LHβ but was different from that of FSHβ. This suggests that α and LHβ mRNA levels are maximally stimulated when GnRHR levels are relatively high, whereas FSHβ mRNA levels are maximally stimulated at lower levels of GnRHR expression, and that the mechanism for differential regulation of the gonadotropins by varying pulse frequencies of GnRH may involve levels of GnRHR. Furthermore, these data suggest that the mechanisms whereby varying GnRH pulse frequencies stimulate α, LHβ, and GnRHR gene expression are similar, whereas the stimulation of FSHβ mRNA levels may be different.

Human Endolymphatic Sac: Evidence for a Role in Inner Ear Immune Defence (With 1 color plate)

ORL ◽  
1990 ◽  
Vol 52 (3) ◽  
pp. 143-148 ◽  
Author(s):  
Hans Jörg Altermatt ◽  
Jan-Olaf Gebbers ◽  
Christoph Müller ◽  
Wolfgang Arnold ◽  
Jean Albert Laissue
Keyword(s):  
Inner Ear ◽  
Endolymphatic Sac ◽  
Immune Defence ◽  
Color Plate

scholarly journals Corticotropin-Releasing Factor Inhibits Luteinizing Hormone-Stimulated P450c17 Gene Expression and Androgen Production by Isolated Thecal Cells of Human Ovarian Follicles1

1998 ◽  
Vol 83 (2) ◽  
pp. 448-452
Author(s):  
H. F. Erden ◽  
I. H. Zwain ◽  
H. Asakura ◽  
S. S. C. Yen
Keyword(s):  
Gene Expression ◽  
Granulosa Cells ◽  
Inhibitory Effect ◽  
Corticotropin Releasing Factor ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Messenger Ribonucleic Acid ◽  
Estrogen Production ◽  
Thecal Cells ◽  
Crf System

Recently, we reported that the thecal compartment of the human ovary contains a CRF system replete with gene expression and protein for corticotropin-releasing factor (CRF), CRF-Receptor 1 (CRF-R1), and the blood-derived high affinity CRF-binding protein (CRF-BP). Granulosa cells are devoid of the CRF system. The parallel increases in intensity of CRF, CRF-R1, and 17α-hydroxylase messenger ribonucleic acid (mRNA) and proteins in thecal cells with follicular maturation suggest that the intraovarian CRF system may play an autocrine role regulating androgen biosynthesis, with a downstream effect on estrogen production by granulosa cells. The functionality of the ovarian CRF system may be conditioned by the relative presence of plasma-derived CRF-BP by virtue of its localization of protein, but not transcript in thecal cells and its ability to compete with CRF for the CRF receptor. To further these findings, in the present study we have examined the effect of CRF on LH-stimulated 17α-hydroxylase (P450c17) gene expression and androgen production by isolated thecal cells from human ovarian follicles (11–13 mm). During the 48-h culture, addition of LH (10 ng/mL) to the medium increased by 5- and 6-fold dehydroepiandrosterone and androstenedione production by thecal cells. Remarkably, the LH-stimulated, but not basal, androgen production was inhibited by CRF in a time- and dose-dependent manner. The half-maximal (ID50) effect dose of CRF occurred at 5 × 10−8 mol/L, and at a maximal concentration of 10−6 mol/L, CRF completely inhibited LH-stimulated androgen production. This inhibitory effect of CRF became evident at 12 h (45%), and by 24 h the effect was more pronounced, with a 70% reduction from baseline. As determined by Northern analyses, CRF dose dependently decreased LH-stimulated P450c17 mRNA levels, with a maximal inhibition of 85% P450c17 gene expression at a CRF concentration of 10−6 mol/L. With the addition of 10−6 mol/L of the antagonist α-helical CRF-(9–41), the inhibitory effect of CRF was partially reversed for both P450c17 mRNA (75%) and androgen production (50%), indicating the CRF-R1-mediated event. In conclusion, the present study demonstrated a potent inhibitory effect of CRF on LH-stimulated dehydroepiandrosterone and androstenedione production that appears to be mediated through the reduction of P450c17 gene expression. Thus, the ovarian CRF system may function as autocrine regulators for androgen biosynthesis in the thecal cell compartment to maintain optimal substrate for estrogen biosynthesis by granulosa cells. Further studies to define the role of CRF-BP in the endocrine modulation of the intraovarian CRF system are needed.

The Role of the Endolymphatic Sac in Inner Ear Immunity

1987 ◽  
Vol 103 (3-4) ◽  
pp. 182-188 ◽  
Author(s):  
Shunichi Tomiyama ◽  
Jeffrey P. Harris
Keyword(s):  
Inner Ear ◽  
Endolymphatic Sac

The Endolymphatic Sac as the Immunocompetent Organ of the Inner Ear

1997 ◽  
Vol 830 (1 Immunologic D) ◽  
pp. 243-252 ◽  
Author(s):  
M. BARBARA ◽  
G. ATTANASIO ◽  
V. PETROZZA ◽  
A. MODESTI ◽  
R. FILIPO
Keyword(s):  
Inner Ear ◽  
Endolymphatic Sac ◽  
Immunocompetent Organ
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