Exclusive nuclear location of estrogen receptors in Squalus testis.
An estrogen (E)-binding molecule having both occupied and unoccupied sites is restricted to nuclear subfractions in the testis of the spiny dogfish (Squalus acanthias). We investigated the hypothesis that a species characterized by high body-fluid osmolarity (1010 mosM) has an estrogen receptor (ER)...
Main Authors: | , |
---|---|
Format: | Text |
Language: | English |
Published: |
1985
|
Subjects: | |
Online Access: | http://www.ncbi.nlm.nih.gov/pmc/articles/PMC397255 http://www.ncbi.nlm.nih.gov/pubmed/3856265 |
id |
ftpubmed:oai:pubmedcentral.nih.gov:397255 |
---|---|
record_format |
openpolar |
spelling |
ftpubmed:oai:pubmedcentral.nih.gov:397255 2023-05-15T18:51:08+02:00 Exclusive nuclear location of estrogen receptors in Squalus testis. Callard, G V Mak, P 1985-03 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC397255 http://www.ncbi.nlm.nih.gov/pubmed/3856265 en eng http://www.ncbi.nlm.nih.gov/pmc/articles/PMC397255 http://www.ncbi.nlm.nih.gov/pubmed/3856265 Research Article Text 1985 ftpubmed 2013-08-29T23:02:26Z An estrogen (E)-binding molecule having both occupied and unoccupied sites is restricted to nuclear subfractions in the testis of the spiny dogfish (Squalus acanthias). We investigated the hypothesis that a species characterized by high body-fluid osmolarity (1010 mosM) has an estrogen receptor (ER) that binds to chromatin with high affinity and consequently resists redistribution during tissue processing. Although the steroid binding and sedimentation properties of the Squalus nuclear ER conformed to those of classical ER, its elution maximum from DNA-cellulose was unusually high (0.55 M NaCl). A tendency to adhere tightly to cell nuclei was reflected in the high salt concentration (0.43 M KCl) required to extract 50% of the receptors from the nuclear compartment during homogenization and in the stability of the nuclear ER population in the presence of high concentrations of a nonionic solute (urea) or increased buffer volume. Mixing and redistribution experiments showed that nuclear ER could be quantitatively and qualitatively measured in cytosolic extracts, ruling out the possibility that soluble receptors were being masked. Although Squalus oviduct ER was similar to that of testis, ER in the testis and liver of a related elasmobranch (Potamotrygon) that maintains osmotic equilibrium at 300 mosM more closely resembled mammalian ER in its elution maximum from DNA-cellulose (0.22 M NaCl) and cytosolic/nuclear ratios in low-salt buffers. We conclude that Squalus testis has a single ER pool located exclusively in the nuclear compartment. These observations support a revised concept of steroid action and further indicate that the chromatin affinity of the hormone-ER complex is an important factor in determining subfractional distribution during tissue processing. Text spiny dogfish Squalus acanthias PubMed Central (PMC) |
institution |
Open Polar |
collection |
PubMed Central (PMC) |
op_collection_id |
ftpubmed |
language |
English |
topic |
Research Article |
spellingShingle |
Research Article Callard, G V Mak, P Exclusive nuclear location of estrogen receptors in Squalus testis. |
topic_facet |
Research Article |
description |
An estrogen (E)-binding molecule having both occupied and unoccupied sites is restricted to nuclear subfractions in the testis of the spiny dogfish (Squalus acanthias). We investigated the hypothesis that a species characterized by high body-fluid osmolarity (1010 mosM) has an estrogen receptor (ER) that binds to chromatin with high affinity and consequently resists redistribution during tissue processing. Although the steroid binding and sedimentation properties of the Squalus nuclear ER conformed to those of classical ER, its elution maximum from DNA-cellulose was unusually high (0.55 M NaCl). A tendency to adhere tightly to cell nuclei was reflected in the high salt concentration (0.43 M KCl) required to extract 50% of the receptors from the nuclear compartment during homogenization and in the stability of the nuclear ER population in the presence of high concentrations of a nonionic solute (urea) or increased buffer volume. Mixing and redistribution experiments showed that nuclear ER could be quantitatively and qualitatively measured in cytosolic extracts, ruling out the possibility that soluble receptors were being masked. Although Squalus oviduct ER was similar to that of testis, ER in the testis and liver of a related elasmobranch (Potamotrygon) that maintains osmotic equilibrium at 300 mosM more closely resembled mammalian ER in its elution maximum from DNA-cellulose (0.22 M NaCl) and cytosolic/nuclear ratios in low-salt buffers. We conclude that Squalus testis has a single ER pool located exclusively in the nuclear compartment. These observations support a revised concept of steroid action and further indicate that the chromatin affinity of the hormone-ER complex is an important factor in determining subfractional distribution during tissue processing. |
format |
Text |
author |
Callard, G V Mak, P |
author_facet |
Callard, G V Mak, P |
author_sort |
Callard, G V |
title |
Exclusive nuclear location of estrogen receptors in Squalus testis. |
title_short |
Exclusive nuclear location of estrogen receptors in Squalus testis. |
title_full |
Exclusive nuclear location of estrogen receptors in Squalus testis. |
title_fullStr |
Exclusive nuclear location of estrogen receptors in Squalus testis. |
title_full_unstemmed |
Exclusive nuclear location of estrogen receptors in Squalus testis. |
title_sort |
exclusive nuclear location of estrogen receptors in squalus testis. |
publishDate |
1985 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC397255 http://www.ncbi.nlm.nih.gov/pubmed/3856265 |
genre |
spiny dogfish Squalus acanthias |
genre_facet |
spiny dogfish Squalus acanthias |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC397255 http://www.ncbi.nlm.nih.gov/pubmed/3856265 |
_version_ |
1766244921784664064 |