DAX-1 (NR0B1) is an orphan nuclear receptor that plays a key role in the development and maintenance of steroidogenic tissue in mammals. Dax-1 is also expressed in mouse embryonic stem (ES) cells and is required to maintain pluripotency. Duplication of the X-chromosome in the region containing the NR0B1 gene results in sex reversal, and mutations in NR0B1 cause adrenal hypoplasia congenita. DAX-1 has been observed to act as a corepressor of other nuclear receptors including androgen receptor (AR), estrogen receptor (ER), and steroidogenic factor 1 (SF-1). In addition to pluripotent ES cells, DAX-1 is primarily expressed in select tissues of the body such as testes, ovaries, adrenal cortex and breast. In some cases, changes in DAX-1 expression may serve as an indicator of aberrant growth. For example, DAX-1 expression is greatly reduced in ER+ breast cancer patient samples and several ER+ cell lines; however the mechanism leading to this change in DAX-1 expression is unknown. Here, we propose that expression of DAX-1 may be governed by epigenetic mechanisms.
We sought to determine whether promoter region CpG island methylation and expression of DAX-1 were inversely related , and if the loss of DAX-1 expression in the breast cancer cell line MCF-7 is due to epigenetic mechanisms. Using gene expression assays and bisulfite sequencing, we have confirmed the relationship between methylation status and DAX-1 expression in MCF7 and A549 cancer cell lines. We have further analyzed the DAX-1 CpG island to observe the presence of epigenetic readers MeCP2 and MBD1 that link methylation to gene repression, suggesting DAX-1 is expressed and regulated differentially by epigenetic mechanisms in the cancer cell lines MCF7 and A549.
","abstract_html":"<p>DAX-1 (NR0B1) is an orphan nuclear receptor that plays a key role in the development and maintenance of steroidogenic tissue in mammals. Dax-1 is also expressed in mouse embryonic stem (ES) cells and is required to maintain pluripotency. Duplication of the X-chromosome in the region containing the NR0B1 gene results in sex reversal, and mutations in NR0B1 cause adrenal hypoplasia congenita. DAX-1 has been observed to act as a corepressor of other nuclear receptors including androgen receptor (AR), estrogen receptor (ER), and steroidogenic factor 1 (SF-1). In addition to pluripotent ES cells, DAX-1 is primarily expressed in select tissues of the body such as testes, ovaries, adrenal cortex and breast. In some cases, changes in DAX-1 expression may serve as an indicator of aberrant growth. For example, DAX-1 expression is greatly reduced in ER+ breast cancer patient samples and several ER+ cell lines; however the mechanism leading to this change in DAX-1 expression is unknown. Here, we propose that expression of DAX-1 may be governed by epigenetic mechanisms. </p> <p>We sought to determine whether promoter region CpG island methylation and expression of DAX-1 were inversely related , and if the loss of DAX-1 expression in the breast cancer cell line MCF-7 is due to epigenetic mechanisms. Using gene expression assays and bisulfite sequencing, we have confirmed the relationship between methylation status and DAX-1 expression in MCF7 and A549 cancer cell lines. We have further analyzed the DAX-1 CpG island to observe the presence of epigenetic readers MeCP2 and MBD1 that link methylation to gene repression, suggesting DAX-1 is expressed and regulated differentially by epigenetic mechanisms in the cancer cell lines MCF7 and A549.</p>","abstract_has_math":false,"creators":["Heskett, Michael B"],"institution":null,"degree_name":"Master of Science in Biology","degree_level":"Thesis","degree_discipline":"Biology","degree_department":null,"school":null,"contributors":["Christina Tzagarakis-Foster","James Sikes","Juliet Spencer"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-12-22T08:00:00Z","date_published":"2014-12-22T08:00:00Z","updated_at":"2026-07-24T05:42:56Z","subjects":["nuclear receptors","DAX-1","NR0B1","endocrinology","hormone receptors","cancer","Biochemistry, Biophysics, and Structural Biology","Biology","Cell and Developmental Biology","Genetics and Genomics"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://repository.usfca.edu/thes/116","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Christina Tzagarakis-Foster","James Sikes","Juliet Spencer"]},{"key":"dc:creator","label":"Author","values":["Heskett, Michael B"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2015-01-07T08:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science in Biology"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["nuclear receptors","DAX-1","NR0B1","endocrinology","hormone receptors","cancer","Biochemistry, Biophysics, and Structural Biology","Biology","Cell and Developmental Biology","Genetics and Genomics"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://repository.usfca.edu/thes/116"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["DAX-1 (NR0B1) is an orphan nuclear receptor that plays a key role in the development and maintenance of steroidogenic tissue in mammals. Dax-1 is also expressed in mouse embryonic stem (ES) cells and is required to maintain pluripotency. Duplication of the X-chromosome in the region containing the NR0B1 gene results in sex reversal, and mutations in NR0B1 cause adrenal hypoplasia congenita. DAX-1 has been observed to act as a corepressor of other nuclear receptors including androgen receptor (AR), estrogen receptor (ER), and steroidogenic factor 1 (SF-1). In addition to pluripotent ES cells, DAX-1 is primarily expressed in select tissues of the body such as testes, ovaries, adrenal cortex and breast. In some cases, changes in DAX-1 expression may serve as an indicator of aberrant growth. For example, DAX-1 expression is greatly reduced in ER+ breast cancer patient samples and several ER+ cell lines; however the mechanism leading to this change in DAX-1 expression is unknown. Here, we propose that expression of DAX-1 may be governed by epigenetic mechanisms.
We sought to determine whether promoter region CpG island methylation and expression of DAX-1 were inversely related , and if the loss of DAX-1 expression in the breast cancer cell line MCF-7 is due to epigenetic mechanisms. Using gene expression assays and bisulfite sequencing, we have confirmed the relationship between methylation status and DAX-1 expression in MCF7 and A549 cancer cell lines. We have further analyzed the DAX-1 CpG island to observe the presence of epigenetic readers MeCP2 and MBD1 that link methylation to gene repression, suggesting DAX-1 is expressed and regulated differentially by epigenetic mechanisms in the cancer cell lines MCF7 and A549.
"]},{"key":"dc:title","label":"Title","values":["Epigenetic Regulation of Nuclear Hormone Receptor DAX-1"]}]}],"canonical_facts":{"dc:contributor":["Christina Tzagarakis-Foster","James Sikes","Juliet Spencer"],"dc:creator":["Heskett, Michael B"],"dc:date.available":["2015-01-07T08:00:00Z"],"dc:description.abstract":["DAX-1 (NR0B1) is an orphan nuclear receptor that plays a key role in the development and maintenance of steroidogenic tissue in mammals. Dax-1 is also expressed in mouse embryonic stem (ES) cells and is required to maintain pluripotency. Duplication of the X-chromosome in the region containing the NR0B1 gene results in sex reversal, and mutations in NR0B1 cause adrenal hypoplasia congenita. DAX-1 has been observed to act as a corepressor of other nuclear receptors including androgen receptor (AR), estrogen receptor (ER), and steroidogenic factor 1 (SF-1). In addition to pluripotent ES cells, DAX-1 is primarily expressed in select tissues of the body such as testes, ovaries, adrenal cortex and breast. In some cases, changes in DAX-1 expression may serve as an indicator of aberrant growth. For example, DAX-1 expression is greatly reduced in ER+ breast cancer patient samples and several ER+ cell lines; however the mechanism leading to this change in DAX-1 expression is unknown. Here, we propose that expression of DAX-1 may be governed by epigenetic mechanisms.
We sought to determine whether promoter region CpG island methylation and expression of DAX-1 were inversely related , and if the loss of DAX-1 expression in the breast cancer cell line MCF-7 is due to epigenetic mechanisms. Using gene expression assays and bisulfite sequencing, we have confirmed the relationship between methylation status and DAX-1 expression in MCF7 and A549 cancer cell lines. We have further analyzed the DAX-1 CpG island to observe the presence of epigenetic readers MeCP2 and MBD1 that link methylation to gene repression, suggesting DAX-1 is expressed and regulated differentially by epigenetic mechanisms in the cancer cell lines MCF7 and A549.
"],"dc:identifier":["https://repository.usfca.edu/thes/116"],"dc:subject":["nuclear receptors","DAX-1","NR0B1","endocrinology","hormone receptors","cancer","Biochemistry, Biophysics, and Structural Biology","Biology","Cell and Developmental Biology","Genetics and Genomics"],"dc:title":["Epigenetic Regulation of Nuclear Hormone Receptor DAX-1"],"thesis:degree_discipline":["Biology"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Master of Science in Biology"]},"updated_at":"2026-07-24T05:42:56Z"}