{"id":{"repo_id":"soton","oai_identifier":"oai:eprints.soton.ac.uk:152861"},"canonical_url":"https://search.dev.ndltd.org/etd/soton/oai:eprints.soton.ac.uk:152861","repository":{"repo_id":"soton","name":"University of Southampton","base_url":"https://eprints.soton.ac.uk/cgi/oai2"},"display":{"title":"Targeting the calcium ATPase to the endoplasmic reticulum","abstract":"The sarco/endoplasmic reticulum calcium ATPase (SERCA) pumps calcium from the<br/>cytoplasm into the lumen of the endoplasmic or sarcoplasmic reticulum (ER/SR), removing<br/>excess Ca2+ from the cytoplasm and replenishing ER/SR Ca2+ stores. SERCA is located in<br/>both the ER and the ER-Golgi intermediate compartment, and so is likely maintained in the<br/>ER by retrieval. To locate the ER retrieval signal(s) in SERCA, a series of chimeric calcium<br/>pumps have been constructed. Sections of SERCA were replaced with corresponding sequence<br/>from its plasma membrane counterpart; plasma membrane calcium ATPase (PMCA).<br/>Replacing the C-terminus of SERCA with corresponding PMCA sequence results in<br/>mistargeting of the protein to the plasma membrane. The opposite construct (consisting of<br/>PMCA with the C-terminus replaced by that of SERCA) is located in the ER, suggesting that<br/>the ER retrieval signal lies towards the C-terminus of the protein. Many of the chimeras built<br/>were located in the ER. This is likely to be due to protein misfolding in some cases. Attempts<br/>were made to detect the unfolded protein response in cells expressing chimeras by measuring<br/>levels of the chaperone protein BiP. BiP upregulation was only seen when the unfolded<br/>protein response was induced pharmacologically, and not in cells expressing chimeras. More<br/>subtle mutagenesis was then carried out to assess the role of the tenth transmembrane domain<br/>of SERCA in ER retrieval and CD8 reporter constructs were used to study the tenth<br/>transmembrane domains of SERCA and PMCA. The study then focussed on determining the<br/>mechanism by which SERCA is retrieved to the ER. Rer1p and BAP31 are both candidate<br/>receptors for the retrieval of SERCA. An antibody to two epitopes in human Rer1p was raised<br/>and characterised. Immunoprecipitation and cross-linking showed that although Rer1p appears<br/>not to interact with SERCA, BAP31 shows a potential interaction and therefore could be involved in the retrieval of the calcium pump to the ER.","abstract_html":"The sarco/endoplasmic reticulum calcium ATPase (SERCA) pumps calcium from the&lt;br/&gt;cytoplasm into the lumen of the endoplasmic or sarcoplasmic reticulum (ER/SR), removing&lt;br/&gt;excess Ca2+ from the cytoplasm and replenishing ER/SR Ca2+ stores. SERCA is located in&lt;br/&gt;both the ER and the ER-Golgi intermediate compartment, and so is likely maintained in the&lt;br/&gt;ER by retrieval. To locate the ER retrieval signal(s) in SERCA, a series of chimeric calcium&lt;br/&gt;pumps have been constructed. Sections of SERCA were replaced with corresponding sequence&lt;br/&gt;from its plasma membrane counterpart; plasma membrane calcium ATPase (PMCA).&lt;br/&gt;Replacing the C-terminus of SERCA with corresponding PMCA sequence results in&lt;br/&gt;mistargeting of the protein to the plasma membrane. The opposite construct (consisting of&lt;br/&gt;PMCA with the C-terminus replaced by that of SERCA) is located in the ER, suggesting that&lt;br/&gt;the ER retrieval signal lies towards the C-terminus of the protein. Many of the chimeras built&lt;br/&gt;were located in the ER. This is likely to be due to protein misfolding in some cases. Attempts&lt;br/&gt;were made to detect the unfolded protein response in cells expressing chimeras by measuring&lt;br/&gt;levels of the chaperone protein BiP. BiP upregulation was only seen when the unfolded&lt;br/&gt;protein response was induced pharmacologically, and not in cells expressing chimeras. More&lt;br/&gt;subtle mutagenesis was then carried out to assess the role of the tenth transmembrane domain&lt;br/&gt;of SERCA in ER retrieval and CD8 reporter constructs were used to study the tenth&lt;br/&gt;transmembrane domains of SERCA and PMCA. The study then focussed on determining the&lt;br/&gt;mechanism by which SERCA is retrieved to the ER. Rer1p and BAP31 are both candidate&lt;br/&gt;receptors for the retrieval of SERCA. An antibody to two epitopes in human Rer1p was raised&lt;br/&gt;and characterised. Immunoprecipitation and cross-linking showed that although Rer1p appears&lt;br/&gt;not to interact with SERCA, BAP31 shows a potential interaction and therefore could be involved in the retrieval of the calcium pump to the ER.","abstract_has_math":false,"creators":["Watson, Helen Rachel"],"institution":"University of Southampton","degree_name":"Ph.D.","degree_level":"doctoral","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["East, J.M.","Lee, A.G."],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009-12","date_published":"2009-12","updated_at":"2026-07-24T04:36:14Z","subjects":[],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["East, J.M.","Lee, A.G."]},{"key":"dc:creator","label":"Author","values":["Watson, Helen Rachel"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2009-12"]},{"key":"dc:date.issued","label":"Date","values":["2009-12"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Biological Sciences (pre 2011 reorg)","School of Biological Sciences"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Southampton"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["https://eprints.soton.ac.uk/152861/"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["Ph.D."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://eprints.soton.ac.uk/152861/1/Helen_Watson_PhD_Thesis.pdf"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The sarco/endoplasmic reticulum calcium ATPase (SERCA) pumps calcium from the<br/>cytoplasm into the lumen of the endoplasmic or sarcoplasmic reticulum (ER/SR), removing<br/>excess Ca2+ from the cytoplasm and replenishing ER/SR Ca2+ stores. SERCA is located in<br/>both the ER and the ER-Golgi intermediate compartment, and so is likely maintained in the<br/>ER by retrieval. To locate the ER retrieval signal(s) in SERCA, a series of chimeric calcium<br/>pumps have been constructed. Sections of SERCA were replaced with corresponding sequence<br/>from its plasma membrane counterpart; plasma membrane calcium ATPase (PMCA).<br/>Replacing the C-terminus of SERCA with corresponding PMCA sequence results in<br/>mistargeting of the protein to the plasma membrane. The opposite construct (consisting of<br/>PMCA with the C-terminus replaced by that of SERCA) is located in the ER, suggesting that<br/>the ER retrieval signal lies towards the C-terminus of the protein. Many of the chimeras built<br/>were located in the ER. This is likely to be due to protein misfolding in some cases. Attempts<br/>were made to detect the unfolded protein response in cells expressing chimeras by measuring<br/>levels of the chaperone protein BiP. BiP upregulation was only seen when the unfolded<br/>protein response was induced pharmacologically, and not in cells expressing chimeras. More<br/>subtle mutagenesis was then carried out to assess the role of the tenth transmembrane domain<br/>of SERCA in ER retrieval and CD8 reporter constructs were used to study the tenth<br/>transmembrane domains of SERCA and PMCA. The study then focussed on determining the<br/>mechanism by which SERCA is retrieved to the ER. Rer1p and BAP31 are both candidate<br/>receptors for the retrieval of SERCA. An antibody to two epitopes in human Rer1p was raised<br/>and characterised. Immunoprecipitation and cross-linking showed that although Rer1p appears<br/>not to interact with SERCA, BAP31 shows a potential interaction and therefore could be involved in the retrieval of the calcium pump to the ER."]},{"key":"dc:format","label":"Dc Format","values":["text"]},{"key":"dc:title","label":"Title","values":["Targeting the calcium ATPase to the endoplasmic reticulum"]}]}],"canonical_facts":{"dc:contributor.advisor":["East, J.M.","Lee, A.G."],"dc:creator":["Watson, Helen Rachel"],"dc:date":["2009-12"],"dc:date.issued":["2009-12"],"dc:description.abstract":["The sarco/endoplasmic reticulum calcium ATPase (SERCA) pumps calcium from the<br/>cytoplasm into the lumen of the endoplasmic or sarcoplasmic reticulum (ER/SR), removing<br/>excess Ca2+ from the cytoplasm and replenishing ER/SR Ca2+ stores. SERCA is located in<br/>both the ER and the ER-Golgi intermediate compartment, and so is likely maintained in the<br/>ER by retrieval. To locate the ER retrieval signal(s) in SERCA, a series of chimeric calcium<br/>pumps have been constructed. Sections of SERCA were replaced with corresponding sequence<br/>from its plasma membrane counterpart; plasma membrane calcium ATPase (PMCA).<br/>Replacing the C-terminus of SERCA with corresponding PMCA sequence results in<br/>mistargeting of the protein to the plasma membrane. The opposite construct (consisting of<br/>PMCA with the C-terminus replaced by that of SERCA) is located in the ER, suggesting that<br/>the ER retrieval signal lies towards the C-terminus of the protein. Many of the chimeras built<br/>were located in the ER. This is likely to be due to protein misfolding in some cases. Attempts<br/>were made to detect the unfolded protein response in cells expressing chimeras by measuring<br/>levels of the chaperone protein BiP. BiP upregulation was only seen when the unfolded<br/>protein response was induced pharmacologically, and not in cells expressing chimeras. More<br/>subtle mutagenesis was then carried out to assess the role of the tenth transmembrane domain<br/>of SERCA in ER retrieval and CD8 reporter constructs were used to study the tenth<br/>transmembrane domains of SERCA and PMCA. The study then focussed on determining the<br/>mechanism by which SERCA is retrieved to the ER. Rer1p and BAP31 are both candidate<br/>receptors for the retrieval of SERCA. An antibody to two epitopes in human Rer1p was raised<br/>and characterised. Immunoprecipitation and cross-linking showed that although Rer1p appears<br/>not to interact with SERCA, BAP31 shows a potential interaction and therefore could be involved in the retrieval of the calcium pump to the ER."],"dc:format":["text"],"dc:identifier.uri":["https://eprints.soton.ac.uk/152861/1/Helen_Watson_PhD_Thesis.pdf"],"dc:publisher.department":["Biological Sciences (pre 2011 reorg)","School of Biological Sciences"],"dc:publisher.institution":["University of Southampton"],"dc:relation.isreferencedby":["https://eprints.soton.ac.uk/152861/"],"dc:title":["Targeting the calcium ATPase to the endoplasmic reticulum"],"dc:type":["Thesis"],"dc:type.qualificationlevel":["doctoral"],"dc:type.qualificationname":["Ph.D."]},"updated_at":"2026-07-24T04:36:14Z"}