{"id":{"repo_id":"edinburgh","oai_identifier":"oai:era.ed.ac.uk:1842/4189"},"canonical_url":"https://search.dev.ndltd.org/etd/edinburgh/oai:era.ed.ac.uk:1842/4189","repository":{"repo_id":"edinburgh","name":"University of Edinburgh","base_url":"https://era.ed.ac.uk/server/oai/request"},"display":{"title":"Control of DAPK-1 degradation","abstract":"DAPK-1 is calcium-calmodulin regulated protein kinase involved in multiple cellular pathways including apoptosis, autophagy, cell survival and motility. The cytokine TNF-α has been reported to induce the degradation of DAPK-1. Here I identified the protease cathepsin B as a novel binding partner of DAPK-1 that protects DAPK-1 from TNF-α induced degradation. Using deletion mutants of DAPK-1, I mapped the cathepsin B binding domain on DAPK-1 to amino acids 836-947. Overexpression of this mini-protein DAPK-1(836-947) facilitated degradation of full-length DAPK-1 and apoptosis induced by TNFR-1. Moreover, siRNA mediated knock-down of DAPK-1 enhanced TNF-α induced apoptosis, confirming the role of DAPK-1 as a survival factor in the TNF-α signalling pathway. In addition, a splice variant of DAPK-1, which I have called s-DAPK-1, was discovered. s-DAPK-1 shares part of DAPK-1’s ankyrin repeats region and cytoskeletal binding domain, and possesses an unique tail region, which contains a cleavage site at its first two amino acids. Unlike DAPK-1, s-DAPK-1 does not contribute to apoptosis induced by high level of MEK/ERK signalling, but it does mimic DAPK-1’s function to induce membrane blebbing. The proteolytically processed form of s-DAPK-1 is more active in the induction of membrane blebbing, which may be due to its higher stability compared to that of full-length s-DAPK-1, suggesting that the tail region can control s-DAPK-1 stability and activity. Co-transfection of s-DAPK-1 and DAPK-1 leads to reduction in DAPK-1 expression level, suggesting a role for s-DAPK-1 to regulate DAPK-1 stability. The kinase domain of DAPK-1 is the region required for s-DAPK-1 to promote DAPK-1 degradation. Surprisingly, s-DAPK-1 does not bind directly to DAPK-1, suggesting that the interaction is indirect and mediated by as yet unidentified accessory proteins. Finally, the experiments with proteasome and lysosome inhibitors indicated that s-DAPK-1 induces DAPK-1 degradation via both lysosome and proteasome pathways.","abstract_html":"DAPK-1 is calcium-calmodulin regulated protein kinase involved in multiple cellular pathways including apoptosis, autophagy, cell survival and motility. The cytokine TNF-α has been reported to induce the degradation of DAPK-1. Here I identified the protease cathepsin B as a novel binding partner of DAPK-1 that protects DAPK-1 from TNF-α induced degradation. Using deletion mutants of DAPK-1, I mapped the cathepsin B binding domain on DAPK-1 to amino acids 836-947. Overexpression of this mini-protein DAPK-1(836-947) facilitated degradation of full-length DAPK-1 and apoptosis induced by TNFR-1. Moreover, siRNA mediated knock-down of DAPK-1 enhanced TNF-α induced apoptosis, confirming the role of DAPK-1 as a survival factor in the TNF-α signalling pathway. In addition, a splice variant of DAPK-1, which I have called s-DAPK-1, was discovered. s-DAPK-1 shares part of DAPK-1’s ankyrin repeats region and cytoskeletal binding domain, and possesses an unique tail region, which contains a cleavage site at its first two amino acids. Unlike DAPK-1, s-DAPK-1 does not contribute to apoptosis induced by high level of MEK/ERK signalling, but it does mimic DAPK-1’s function to induce membrane blebbing. The proteolytically processed form of s-DAPK-1 is more active in the induction of membrane blebbing, which may be due to its higher stability compared to that of full-length s-DAPK-1, suggesting that the tail region can control s-DAPK-1 stability and activity. Co-transfection of s-DAPK-1 and DAPK-1 leads to reduction in DAPK-1 expression level, suggesting a role for s-DAPK-1 to regulate DAPK-1 stability. The kinase domain of DAPK-1 is the region required for s-DAPK-1 to promote DAPK-1 degradation. Surprisingly, s-DAPK-1 does not bind directly to DAPK-1, suggesting that the interaction is indirect and mediated by as yet unidentified accessory proteins. Finally, the experiments with proteasome and lysosome inhibitors indicated that s-DAPK-1 induces DAPK-1 degradation via both lysosome and proteasome pathways.","abstract_has_math":false,"creators":["Lin, Yao"],"institution":"The University of Edinburgh","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Hupp, Ted"],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009","date_published":"2009","updated_at":"2026-07-24T02:13:53Z","subjects":["DAPK-1","kinase","degradation","apoptosis"],"languages":["en"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/1842/4189","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Hupp, Ted"]},{"key":"dc:creator","label":"Author","values":["Lin, Yao"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2010-11-05T16:28:29Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2010-11-05T16:28:29Z"]},{"key":"dc:date.issued","label":"Date","values":["2009"]},{"key":"dc:publisher","label":"Institution","values":["The University of Edinburgh"]},{"key":"dc:type","label":"Dc Type","values":["Thesis or Dissertation"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["PhD Doctor of Philosophy"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["DAPK-1","kinase","degradation","apoptosis"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/1842/4189"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["DAPK-1 is calcium-calmodulin regulated protein kinase involved in multiple cellular pathways including apoptosis, autophagy, cell survival and motility. The cytokine TNF-α has been reported to induce the degradation of DAPK-1. Here I identified the protease cathepsin B as a novel binding partner of DAPK-1 that protects DAPK-1 from TNF-α induced degradation. Using deletion mutants of DAPK-1, I mapped the cathepsin B binding domain on DAPK-1 to amino acids 836-947. Overexpression of this mini-protein DAPK-1(836-947) facilitated degradation of full-length DAPK-1 and apoptosis induced by TNFR-1. Moreover, siRNA mediated knock-down of DAPK-1 enhanced TNF-α induced apoptosis, confirming the role of DAPK-1 as a survival factor in the TNF-α signalling pathway. In addition, a splice variant of DAPK-1, which I have called s-DAPK-1, was discovered. s-DAPK-1 shares part of DAPK-1’s ankyrin repeats region and cytoskeletal binding domain, and possesses an unique tail region, which contains a cleavage site at its first two amino acids. Unlike DAPK-1, s-DAPK-1 does not contribute to apoptosis induced by high level of MEK/ERK signalling, but it does mimic DAPK-1’s function to induce membrane blebbing. The proteolytically processed form of s-DAPK-1 is more active in the induction of membrane blebbing, which may be due to its higher stability compared to that of full-length s-DAPK-1, suggesting that the tail region can control s-DAPK-1 stability and activity. Co-transfection of s-DAPK-1 and DAPK-1 leads to reduction in DAPK-1 expression level, suggesting a role for s-DAPK-1 to regulate DAPK-1 stability. The kinase domain of DAPK-1 is the region required for s-DAPK-1 to promote DAPK-1 degradation. Surprisingly, s-DAPK-1 does not bind directly to DAPK-1, suggesting that the interaction is indirect and mediated by as yet unidentified accessory proteins. Finally, the experiments with proteasome and lysosome inhibitors indicated that s-DAPK-1 induces DAPK-1 degradation via both lysosome and proteasome pathways."]},{"key":"dc:title","label":"Title","values":["Control of DAPK-1 degradation"]}]}],"canonical_facts":{"dc:contributor.advisor":["Hupp, Ted"],"dc:creator":["Lin, Yao"],"dc:date.accessioned":["2010-11-05T16:28:29Z"],"dc:date.available":["2010-11-05T16:28:29Z"],"dc:date.issued":["2009"],"dc:description.abstract":["DAPK-1 is calcium-calmodulin regulated protein kinase involved in multiple cellular pathways including apoptosis, autophagy, cell survival and motility. The cytokine TNF-α has been reported to induce the degradation of DAPK-1. Here I identified the protease cathepsin B as a novel binding partner of DAPK-1 that protects DAPK-1 from TNF-α induced degradation. Using deletion mutants of DAPK-1, I mapped the cathepsin B binding domain on DAPK-1 to amino acids 836-947. Overexpression of this mini-protein DAPK-1(836-947) facilitated degradation of full-length DAPK-1 and apoptosis induced by TNFR-1. Moreover, siRNA mediated knock-down of DAPK-1 enhanced TNF-α induced apoptosis, confirming the role of DAPK-1 as a survival factor in the TNF-α signalling pathway. In addition, a splice variant of DAPK-1, which I have called s-DAPK-1, was discovered. s-DAPK-1 shares part of DAPK-1’s ankyrin repeats region and cytoskeletal binding domain, and possesses an unique tail region, which contains a cleavage site at its first two amino acids. Unlike DAPK-1, s-DAPK-1 does not contribute to apoptosis induced by high level of MEK/ERK signalling, but it does mimic DAPK-1’s function to induce membrane blebbing. The proteolytically processed form of s-DAPK-1 is more active in the induction of membrane blebbing, which may be due to its higher stability compared to that of full-length s-DAPK-1, suggesting that the tail region can control s-DAPK-1 stability and activity. Co-transfection of s-DAPK-1 and DAPK-1 leads to reduction in DAPK-1 expression level, suggesting a role for s-DAPK-1 to regulate DAPK-1 stability. The kinase domain of DAPK-1 is the region required for s-DAPK-1 to promote DAPK-1 degradation. Surprisingly, s-DAPK-1 does not bind directly to DAPK-1, suggesting that the interaction is indirect and mediated by as yet unidentified accessory proteins. Finally, the experiments with proteasome and lysosome inhibitors indicated that s-DAPK-1 induces DAPK-1 degradation via both lysosome and proteasome pathways."],"dc:identifier.uri":["http://hdl.handle.net/1842/4189"],"dc:language.iso":["en"],"dc:publisher":["The University of Edinburgh"],"dc:subject":["DAPK-1","kinase","degradation","apoptosis"],"dc:title":["Control of DAPK-1 degradation"],"dc:type":["Thesis or Dissertation"],"dc:type.qualificationlevel":["Doctoral"],"dc:type.qualificationname":["PhD Doctor of Philosophy"]},"updated_at":"2026-07-24T02:13:53Z"}