Selected imprinting of <it>INS</it> in the marsupial
<p>Abstract</p> <p>Background</p> <p>In marsupials, growth and development of the young occur postnatally, regulated by milk that changes in composition throughout the long lactation. To initiate lactation in mammals, there is an absolute requirement for insulin (<it...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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BMC
2012-08-01
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| Series: | Epigenetics & Chromatin |
| Subjects: | |
| Online Access: | http://www.epigeneticsandchromatin.com/content/5/1/14 |
| _version_ | 1819024691980926976 |
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| author | Stringer Jessica M Suzuki Shunsuke Pask Andrew J Shaw Geoff Renfree Marilyn B |
| author_facet | Stringer Jessica M Suzuki Shunsuke Pask Andrew J Shaw Geoff Renfree Marilyn B |
| author_sort | Stringer Jessica M |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p>In marsupials, growth and development of the young occur postnatally, regulated by milk that changes in composition throughout the long lactation. To initiate lactation in mammals, there is an absolute requirement for insulin (<it>INS</it>), a gene known to be imprinted in the placenta. We therefore examined whether <it>INS</it> is imprinted in the mammary gland of the marsupial tammar wallaby (<it>Macropus eugenii</it>) and compared its expression with that of insulin-like growth factor 2 (<it>IGF2</it>).</p> <p>Results</p> <p><it>INS</it> was expressed in the mammary gland and significantly increased, while <it>IGF2</it> decreased, during established milk production. Insulin and IGF2 were both detected in the mammary gland macrophage cells during early lactation and in the alveolar cells later in lactation. Surprisingly, <it>INS</it>, which was thought only to be imprinted in the therian yolk sac, was imprinted and paternally expressed in the liver of the developing young, monoallelically expressed in the tammar mammary gland and biallelic in the stomach and intestine. The <it>INS</it> transcription start site used in the liver and mammary gland was differentially methylated.</p> <p>Conclusions</p> <p>This is the first study to identify tissue-specific <it>INS</it> imprinting outside the yolk sac. These data suggest that there may be an advantage of selective monoallelic expression in the mammary gland and that this may influence the growth of the postnatal young. These results are not consistent with the parental conflict hypothesis, but instead provide support for the maternal–infant co-adaptation hypothesis. Thus, imprinting in the mammary gland maybe as critical for postnatal growth and development in mammals as genomic imprinting in the placenta is prenatally.</p> |
| first_indexed | 2024-12-21T04:58:49Z |
| format | Article |
| id | doaj.art-24872614a7d2405e917decfa94a27fa0 |
| institution | Directory Open Access Journal |
| issn | 1756-8935 |
| language | English |
| last_indexed | 2024-12-21T04:58:49Z |
| publishDate | 2012-08-01 |
| publisher | BMC |
| record_format | Article |
| series | Epigenetics & Chromatin |
| spelling | doaj.art-24872614a7d2405e917decfa94a27fa02022-12-21T19:15:17ZengBMCEpigenetics & Chromatin1756-89352012-08-01511410.1186/1756-8935-5-14Selected imprinting of <it>INS</it> in the marsupialStringer Jessica MSuzuki ShunsukePask Andrew JShaw GeoffRenfree Marilyn B<p>Abstract</p> <p>Background</p> <p>In marsupials, growth and development of the young occur postnatally, regulated by milk that changes in composition throughout the long lactation. To initiate lactation in mammals, there is an absolute requirement for insulin (<it>INS</it>), a gene known to be imprinted in the placenta. We therefore examined whether <it>INS</it> is imprinted in the mammary gland of the marsupial tammar wallaby (<it>Macropus eugenii</it>) and compared its expression with that of insulin-like growth factor 2 (<it>IGF2</it>).</p> <p>Results</p> <p><it>INS</it> was expressed in the mammary gland and significantly increased, while <it>IGF2</it> decreased, during established milk production. Insulin and IGF2 were both detected in the mammary gland macrophage cells during early lactation and in the alveolar cells later in lactation. Surprisingly, <it>INS</it>, which was thought only to be imprinted in the therian yolk sac, was imprinted and paternally expressed in the liver of the developing young, monoallelically expressed in the tammar mammary gland and biallelic in the stomach and intestine. The <it>INS</it> transcription start site used in the liver and mammary gland was differentially methylated.</p> <p>Conclusions</p> <p>This is the first study to identify tissue-specific <it>INS</it> imprinting outside the yolk sac. These data suggest that there may be an advantage of selective monoallelic expression in the mammary gland and that this may influence the growth of the postnatal young. These results are not consistent with the parental conflict hypothesis, but instead provide support for the maternal–infant co-adaptation hypothesis. Thus, imprinting in the mammary gland maybe as critical for postnatal growth and development in mammals as genomic imprinting in the placenta is prenatally.</p>http://www.epigeneticsandchromatin.com/content/5/1/14Genomic imprintingMammary glandLactationMarsupialInsulinCo-adaptation |
| spellingShingle | Stringer Jessica M Suzuki Shunsuke Pask Andrew J Shaw Geoff Renfree Marilyn B Selected imprinting of <it>INS</it> in the marsupial Epigenetics & Chromatin Genomic imprinting Mammary gland Lactation Marsupial Insulin Co-adaptation |
| title | Selected imprinting of <it>INS</it> in the marsupial |
| title_full | Selected imprinting of <it>INS</it> in the marsupial |
| title_fullStr | Selected imprinting of <it>INS</it> in the marsupial |
| title_full_unstemmed | Selected imprinting of <it>INS</it> in the marsupial |
| title_short | Selected imprinting of <it>INS</it> in the marsupial |
| title_sort | selected imprinting of it ins it in the marsupial |
| topic | Genomic imprinting Mammary gland Lactation Marsupial Insulin Co-adaptation |
| url | http://www.epigeneticsandchromatin.com/content/5/1/14 |
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