Alanine, proline and urea are major organic osmolytes in the snail Theodoxus fluviatilis under hyperosmotic stress

In diverse organisms, cells adapt to hyperosmotic stress by accumulating organic osmolytes. Mammalian renal medullary cells are routinely under osmotic stress. Two renal cell lines, Madin-Darby canine kidney (MDCK) and PAP-HT25, have been widely used to study mammalian osmotic regulation. In these epithelial cells, extracellular hypertonicity induces gene transcription of proteins directly involved in the metabolism and transport of organic osmolytes. This induction is relatively specific and not part of a generalized stress response. Little is known about the signal transduction pathway between cellular detection of extracellular osmolality and increased specific gene transcription. Here, using differential mRNA display polymerase chain reaction on MDCK cells in isotonic vs. hypertonic medium, we identify a cDNA product corresponding to CD9 antigen mRNA. CD9 antigen is a cell surface glycoprotein originally found in cells of the immune system. Although CD9 antigen has been structurally characterized, its function is unclear. We further demonstrate that CD9 antigen mRNA is present in MDCK and PAP-HT25 cells and that its mRNA abundance is induced by extracellular hypertonicity, but not by heat stress. Also, we show that accumulation of organic osmolytes markedly attenuates the CD9 mRNA induction, as only recently demonstrated with genes involved in the hyperosmotic stress response. This suggests a role for CD9 antigen in this response.

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Induction of molecular chaperones by hyperosmotic stress in mouse inner medullary collecting duct cells

AJP Renal Physiology ◽

10.1152/ajprenal.1997.273.1.f9 ◽

1997 ◽

Vol 273 (1) ◽

pp. F9-F17 ◽

Cited By ~ 9

Author(s):

M. I. Rauchman ◽

J. Pullman ◽

S. R. Gullans

Keyword(s):

Heat Shock ◽

Molecular Chaperones ◽

Collecting Duct ◽

Hyperosmotic Stress ◽

Affinity Column ◽

Organic Osmolytes ◽

Cellular Functions ◽

Inner Medullary Collecting Duct ◽

Medullary Collecting Duct

The extreme hyperosmotic conditions that exist in the renal inner medulla enable the urinary concentrating mechanism to function. In this study, we evaluated whether stress-related molecular chaperones are induced in response to hyperosmotic stress in mouse inner medullary collecting duct (mIMCD3) cells. Exposure of cells to medium supplemented with 100 mM NaCl for 4 or 24 h resulted in an increase in heat shock protein-72 (HSP-72) (inducible form) by Western blot. Immunocytochemistry confirmed the increase of HSP-72 and showed that hyperosmotic stress resulted in a localization of HSP-72 predominantly to the nucleoplasm that surrounds the nucleoli and to the cytoplasm, a subcellular distribution pattern different from that seen with heat shock. Using a denatured protein (casein)-affinity column with ATP elution, we identified a number of putative molecular chaperones (46, 60, 78, and 200 kDa) that are upregulated in response to 4 h of hyperosmotic NaCl treatment. Microsequencing identified one of these proteins to be the mitochondrial chaperone mtHSP-70, a member of HSP-70 family, and another to be similar to beta-actin. We also found high levels of HSP-72 in cells chronically adapted to hypertonicity, indicating that chaperones are still required to maintain certain cellular functions even after nonperturbing organic osmolytes are known to accumulate. These results suggest an important role for molecular chaperones in the adaptation of renal medullary epithelial cells to the hyperosmotic conditions that exist in the inner medulla in vivo.

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Distribution of Theodoxus fluviatilis L. in the Dniester River and the Influence of the Hydroelectric Power Stations on the Structure of its Population

Hydrobiological Journal ◽

10.1615/hydrobj.v42.i5.20 ◽

2006 ◽

Vol 42 (5) ◽

pp. 12-24

Author(s):

L. V. Shevtsova ◽

A. I. Tsybulskiy

Keyword(s):

Hydroelectric Power ◽

Power Stations ◽

Theodoxus Fluviatilis

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Hyperosmotic stress induces readthrough transcripts and changes to the Pol II interactome despite widespread transcriptional repression

10.26226/morressier.5ebd45acffea6f735881aed5 ◽

2020 ◽

Author(s):

Nicolle Rosa Mercado

Keyword(s):

Transcriptional Repression ◽

Hyperosmotic Stress ◽

Pol Ii

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Faculty Opinions recommendation of Hyperosmotic stress memory in Arabidopsis is mediated by distinct epigenetically labile sites in the genome and is restricted in the male germline by DNA glycosylase activity.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.726388119.793539722 ◽

2017 ◽

Author(s):

Xiaoqi Feng

Keyword(s):

Hyperosmotic Stress ◽

Dna Glycosylase ◽

Stress Memory ◽

Male Germline

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Faculty Opinions recommendation of Humidity-regulated CLCA2 protects the epidermis from hyperosmotic stress.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.733211714.793550778 ◽

2018 ◽

Author(s):

Kilian Eyerich

Keyword(s):

Hyperosmotic Stress

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Regeneration of Floodplain Biotopes on the Upper Rhine – The “Polder Altenheim” Case

Water Science & Technology ◽

10.2166/wst.1994.0121 ◽

1994 ◽

Vol 29 (3) ◽

pp. 281-288 ◽

Cited By ~ 6

Author(s):

A. Siepe

Keyword(s):

Large Scale ◽

Freshwater Snail ◽

Red Alga ◽

Flood Protection ◽

Flooding Regime ◽

Theodoxus Fluviatilis ◽

The Creation ◽

Early Succession ◽

Upper Rhine

The floodplain of the Upper Rhine and its biocoenoses have, through different river-regulatory activities over the last 175 years, undergone large scale degradation. At the same time flood protection for the downstream inhabitants has been greatly reduced. For reasons of flood protection, the “Polder Altenheim” in Baden-Württemberg, Germany southwest of Strasbourg, France, with so called retention flooding, was put into operation in 1987. The original floodplain had been diked for the previous 17 years, during which no flooding occurred. Since 1989 “ecological flooding” also is carried out. This has assisted in the regeneration of floodplain biotopes and promoted the floodplain biotic communities and the readaption of the bioceonosis to a regular flooding regime. The creation of new floodplain biotopes of early succession stages, particularly through geomorphodynamic processes, has followed the more than ten flood ocassions and typical biotic communities have colonised these sites. This will be presented together with selected examples of terrestrial and limnical species and communities. The following species and communities will be discussed: kingfisher Alcedo atthis, carabid communities (Coleoptera), the red alga Hildenbrandia rivularis (Rhodophyceae), the freshwater snail Theodoxus fluviatilis (Neritacea) and the freshwater bug Aphelocheirus aestivalis (Hydrocorisae).

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