{"id":{"repo_id":"radboud","oai_identifier":"oai:repository.ubn.ru.nl:2066/27006"},"canonical_url":"https://search.dev.ndltd.org/etd/radboud/oai:repository.ubn.ru.nl:2066/27006","repository":{"repo_id":"radboud","name":"Radboud University Nijmegen","base_url":"https://repository.ubn.ru.nl/oai/request"},"display":{"title":"New sides of an old factor: TFIIA function and regulation","abstract":"Contains fulltext : 27006.pdf (Publisher’s version ) (Open Access)","abstract_html":"Contains fulltext : 27006.pdf (Publisher’s version ) (Open Access)","abstract_has_math":false,"creators":["Hoiby, T."],"institution":"[S.l.] : [S.n.]","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Stunnenberg, H.G."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2005,"date_issued":"2005","date_published":"2005","updated_at":"2026-07-24T04:03:01Z","subjects":["Molecular Biology"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2066/32781","909019925X"],"render_values":[{"text":"http://hdl.handle.net/2066/32781","href":"http://hdl.handle.net/2066/32781","code":true},{"text":"909019925X","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2066/27006","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Stunnenberg, H.G."]},{"key":"dc:creator","label":"Author","values":["Hoiby, T."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2005"]},{"key":"dc:publisher","label":"Institution","values":["[S.l.] : [S.n.]"]},{"key":"dc:type","label":"Dc Type","values":["Doctoral thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Molecular Biology"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://repository.ubn.ru.nl//bitstream/handle/2066/27006/27006.pdf","http://hdl.handle.net/2066/27006","http://hdl.handle.net/2066/32781","909019925X"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Contains fulltext : 27006.pdf (Publisher’s version ) (Open Access)","TFIIA was originally identified as one of the general transcription factors, activating transcription by stabilizing TBP binding to DNA and through functioning as a co-activator and anti-repressor. Its classification as such was recently disputed by observations showing that TFIIA is involved in transcriptional activation of only a subset of promoters. We have found that the posttranslational proteolytic processing of TFIIA to TFIIA and - occurs N-terminally of D278 and further depends on the identity of a string of 4 amino acids directly to the N-terminus of D278, the so-called cleavage recognition site (CRS) of TFIIA. Utilising single TFIIA CRS mutants that were uncleavable, we were able to show that the uncleavable TFIIA and wild-type TFIIA behave indistinguishably in classical TFIIA assays like DNA-TBP-TFIIA bandshifts and transcriptional activity assays. The only discernable difference was the striking accumulation of cellular levels of uncleavable TFIIA, arguing that the proper turn-over of these mutants was impaired. Using pulse-chase assays we found that the stability of TFIIA was largely dependent on its cleavage and, consistently, that the wild-type TFIIA was less stable than the uncleavable CRS mutants. Furthermore, only the cleaved form of TFIIA is poly-ubiquitylated and susceptible to proteasomal degradation, suggesting that cleavage may be part of the cellular pathway of regulation of cellular TFIIA levels. Furthermore, it seems that the cleavage and stability of TFIIA further depends on various phosphorylation sites surrounding the cleavage region, adding further complexity and nuances to TFIIA turnover. Strikingly, we found that the TFIIA CRS was identical to the cleavage region of MLL (Mixed Myeloid Leukaemia). We found that Taspase1, the recently identified MLL protease, was able to cleave TFIIA, both in vivo and in vitro. The unexpected link between these two seemingly unrelated proteins raises the logical question and allows for an intriguing line of research: is cleavage of TFIIA and MLL a functionally co-regulated process during development or is their interconnectedness limited to sharing a protease? In conclusion, the work described here concerning the proteolytical cleavage of TFIIA therefore reveals unexpected layers of complexity in TFIIA regulation.","RU Radboud Universiteit Nijmegen, 31 oktober 2005","Promotor : Stunnenberg, H.G.","172 p."]},{"key":"dc:title","label":"Title","values":["New sides of an old factor: TFIIA function and regulation"]}]}],"canonical_facts":{"dc:contributor":["Stunnenberg, H.G."],"dc:creator":["Hoiby, T."],"dc:date":["2005"],"dc:description":["Contains fulltext : 27006.pdf (Publisher’s version ) (Open Access)","TFIIA was originally identified as one of the general transcription factors, activating transcription by stabilizing TBP binding to DNA and through functioning as a co-activator and anti-repressor. Its classification as such was recently disputed by observations showing that TFIIA is involved in transcriptional activation of only a subset of promoters. We have found that the posttranslational proteolytic processing of TFIIA to TFIIA and - occurs N-terminally of D278 and further depends on the identity of a string of 4 amino acids directly to the N-terminus of D278, the so-called cleavage recognition site (CRS) of TFIIA. Utilising single TFIIA CRS mutants that were uncleavable, we were able to show that the uncleavable TFIIA and wild-type TFIIA behave indistinguishably in classical TFIIA assays like DNA-TBP-TFIIA bandshifts and transcriptional activity assays. The only discernable difference was the striking accumulation of cellular levels of uncleavable TFIIA, arguing that the proper turn-over of these mutants was impaired. Using pulse-chase assays we found that the stability of TFIIA was largely dependent on its cleavage and, consistently, that the wild-type TFIIA was less stable than the uncleavable CRS mutants. Furthermore, only the cleaved form of TFIIA is poly-ubiquitylated and susceptible to proteasomal degradation, suggesting that cleavage may be part of the cellular pathway of regulation of cellular TFIIA levels. Furthermore, it seems that the cleavage and stability of TFIIA further depends on various phosphorylation sites surrounding the cleavage region, adding further complexity and nuances to TFIIA turnover. Strikingly, we found that the TFIIA CRS was identical to the cleavage region of MLL (Mixed Myeloid Leukaemia). We found that Taspase1, the recently identified MLL protease, was able to cleave TFIIA, both in vivo and in vitro. The unexpected link between these two seemingly unrelated proteins raises the logical question and allows for an intriguing line of research: is cleavage of TFIIA and MLL a functionally co-regulated process during development or is their interconnectedness limited to sharing a protease? In conclusion, the work described here concerning the proteolytical cleavage of TFIIA therefore reveals unexpected layers of complexity in TFIIA regulation.","RU Radboud Universiteit Nijmegen, 31 oktober 2005","Promotor : Stunnenberg, H.G.","172 p."],"dc:identifier":["https://repository.ubn.ru.nl//bitstream/handle/2066/27006/27006.pdf","http://hdl.handle.net/2066/27006","http://hdl.handle.net/2066/32781","909019925X"],"dc:publisher":["[S.l.] : [S.n.]"],"dc:subject":["Molecular Biology"],"dc:title":["New sides of an old factor: TFIIA function and regulation"],"dc:type":["Doctoral thesis"]},"updated_at":"2026-07-24T04:03:01Z"}