{"id":{"repo_id":"wfu","oai_identifier":"oai:wakespace.lib.wfu.edu:10339/39141"},"canonical_url":"https://search.dev.ndltd.org/etd/wfu/oai:wakespace.lib.wfu.edu:10339/39141","repository":{"repo_id":"wfu","name":"Wake Forest University","base_url":"https://wakespace.lib.wfu.edu/oai/request"},"display":{"title":"G4-RESOLVASE 1 TIGHTLY BINDS AND CATALYTICALLY UNWINDS UNIMOLECULAR G-QUADRUPLEX STRUCTURES WITH IMPLICATIONS FOR GENE TRANSCRIPTION AND TELOMERE BIOLOGY","abstract":"G-quadruplexes (G4s) are four-stranded structures formed by guanine-rich DNA or RNA sequences in which the strands can be orientated in parallel, antiparallel, or mixed parallel/antiparallel orientations. It has been previously shown that the DHX36 gene product, G4-Resolvase1 (G4R1), binds parallel tetramolecular G4-DNA with high affinity and resolves these structures into single strands. Here we show that G4R1 specifically binds to a parallel, unimolecular G4-DNA with remarkable affinity, with Kd values in the low pM range; the tightest reported binding affinity for any known G4-binding protein. Using a novel peptide nucleic acid (PNA) trap assay, we show that G4R1 catalyzes unwinding of unimolecular G4-DNA into an unstructured state. Additionally, we provide strong evidence for the presence of unimolecular G4-structures in the promoter of the Yin Yang 1 (YY1) gene and demonstrate that these structures have an inhibitory effect on reporter assay expression. We also discovered that G4R1 directly binds and unwinds G4-structures in the YY1 promoter, subsequently enhancing reporter expression. Consistently, ectopically expressed G4R1 increased endogenous YY1 levels and gene array analysis consisting of 258 patient breast cancer samples indicated a significant, positive correlation between G4R1 and YY1 expression. We went on to demonstrate that G4R1 tightly binds to mixed parallel/antiparallel and antiparallel unimolecular telomeric G4-DNA. Furthermore, we show specific requirements of G4R1 for tight binding to telomeric DNA which are: 1) presence of G4-structure in the sequence and 2) a guanine-containing 3'-tail. Overall findings from this dissertation strongly suggest that G4R1 tightly and specifically binds to an exceptional array of G4-structures and could potentially serve as a \"pan\" G4-resolver in the cell. Indeed this finding could have significant genomic impact, as >375,000 G4-forming motifs exist in the genome and G4-structures have been shown to play prominent regulatory roles in transcription, translation, replication, immunoglobin switching, and telomere biology.","abstract_html":"G-quadruplexes (G4s) are four-stranded structures formed by guanine-rich DNA or RNA sequences in which the strands can be orientated in parallel, antiparallel, or mixed parallel/antiparallel orientations. It has been previously shown that the DHX36 gene product, G4-Resolvase1 (G4R1), binds parallel tetramolecular G4-DNA with high affinity and resolves these structures into single strands. Here we show that G4R1 specifically binds to a parallel, unimolecular G4-DNA with remarkable affinity, with Kd values in the low pM range; the tightest reported binding affinity for any known G4-binding protein. Using a novel peptide nucleic acid (PNA) trap assay, we show that G4R1 catalyzes unwinding of unimolecular G4-DNA into an unstructured state. Additionally, we provide strong evidence for the presence of unimolecular G4-structures in the promoter of the Yin Yang 1 (YY1) gene and demonstrate that these structures have an inhibitory effect on reporter assay expression. We also discovered that G4R1 directly binds and unwinds G4-structures in the YY1 promoter, subsequently enhancing reporter expression. Consistently, ectopically expressed G4R1 increased endogenous YY1 levels and gene array analysis consisting of 258 patient breast cancer samples indicated a significant, positive correlation between G4R1 and YY1 expression. We went on to demonstrate that G4R1 tightly binds to mixed parallel/antiparallel and antiparallel unimolecular telomeric G4-DNA. Furthermore, we show specific requirements of G4R1 for tight binding to telomeric DNA which are: 1) presence of G4-structure in the sequence and 2) a guanine-containing 3'-tail. Overall findings from this dissertation strongly suggest that G4R1 tightly and specifically binds to an exceptional array of G4-structures and could potentially serve as a "pan" G4-resolver in the cell. Indeed this finding could have significant genomic impact, as >375,000 G4-forming motifs exist in the genome and G4-structures have been shown to play prominent regulatory roles in transcription, translation, replication, immunoglobin switching, and telomere biology.","abstract_has_math":false,"creators":["Smaldino, Phillip James"],"institution":"Wake Forest University","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2013,"date_issued":"2013","date_published":"2013","updated_at":"2026-07-27T22:01:39Z","subjects":["dhx36"],"languages":["en"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10339/39141","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Smaldino, Phillip James"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-01-15T09:35:36Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-07-15T08:30:09Z"]},{"key":"dc:date.issued","label":"Date","values":["2013"]},{"key":"dc:publisher","label":"Institution","values":["Wake Forest University"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["dhx36"]}]},{"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/10339/39141"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["G-quadruplexes (G4s) are four-stranded structures formed by guanine-rich DNA or RNA sequences in which the strands can be orientated in parallel, antiparallel, or mixed parallel/antiparallel orientations. It has been previously shown that the DHX36 gene product, G4-Resolvase1 (G4R1), binds parallel tetramolecular G4-DNA with high affinity and resolves these structures into single strands. Here we show that G4R1 specifically binds to a parallel, unimolecular G4-DNA with remarkable affinity, with Kd values in the low pM range; the tightest reported binding affinity for any known G4-binding protein. Using a novel peptide nucleic acid (PNA) trap assay, we show that G4R1 catalyzes unwinding of unimolecular G4-DNA into an unstructured state. Additionally, we provide strong evidence for the presence of unimolecular G4-structures in the promoter of the Yin Yang 1 (YY1) gene and demonstrate that these structures have an inhibitory effect on reporter assay expression. We also discovered that G4R1 directly binds and unwinds G4-structures in the YY1 promoter, subsequently enhancing reporter expression. Consistently, ectopically expressed G4R1 increased endogenous YY1 levels and gene array analysis consisting of 258 patient breast cancer samples indicated a significant, positive correlation between G4R1 and YY1 expression. We went on to demonstrate that G4R1 tightly binds to mixed parallel/antiparallel and antiparallel unimolecular telomeric G4-DNA. Furthermore, we show specific requirements of G4R1 for tight binding to telomeric DNA which are: 1) presence of G4-structure in the sequence and 2) a guanine-containing 3'-tail. Overall findings from this dissertation strongly suggest that G4R1 tightly and specifically binds to an exceptional array of G4-structures and could potentially serve as a \"pan\" G4-resolver in the cell. Indeed this finding could have significant genomic impact, as >375,000 G4-forming motifs exist in the genome and G4-structures have been shown to play prominent regulatory roles in transcription, translation, replication, immunoglobin switching, and telomere biology."]},{"key":"dc:title","label":"Title","values":["G4-RESOLVASE 1 TIGHTLY BINDS AND CATALYTICALLY UNWINDS UNIMOLECULAR G-QUADRUPLEX STRUCTURES WITH IMPLICATIONS FOR GENE TRANSCRIPTION AND TELOMERE BIOLOGY"]}]}],"canonical_facts":{"dc:creator":["Smaldino, Phillip James"],"dc:date.accessioned":["2014-01-15T09:35:36Z"],"dc:date.available":["2014-07-15T08:30:09Z"],"dc:date.issued":["2013"],"dc:description.abstract":["G-quadruplexes (G4s) are four-stranded structures formed by guanine-rich DNA or RNA sequences in which the strands can be orientated in parallel, antiparallel, or mixed parallel/antiparallel orientations. It has been previously shown that the DHX36 gene product, G4-Resolvase1 (G4R1), binds parallel tetramolecular G4-DNA with high affinity and resolves these structures into single strands. Here we show that G4R1 specifically binds to a parallel, unimolecular G4-DNA with remarkable affinity, with Kd values in the low pM range; the tightest reported binding affinity for any known G4-binding protein. Using a novel peptide nucleic acid (PNA) trap assay, we show that G4R1 catalyzes unwinding of unimolecular G4-DNA into an unstructured state. Additionally, we provide strong evidence for the presence of unimolecular G4-structures in the promoter of the Yin Yang 1 (YY1) gene and demonstrate that these structures have an inhibitory effect on reporter assay expression. We also discovered that G4R1 directly binds and unwinds G4-structures in the YY1 promoter, subsequently enhancing reporter expression. Consistently, ectopically expressed G4R1 increased endogenous YY1 levels and gene array analysis consisting of 258 patient breast cancer samples indicated a significant, positive correlation between G4R1 and YY1 expression. We went on to demonstrate that G4R1 tightly binds to mixed parallel/antiparallel and antiparallel unimolecular telomeric G4-DNA. Furthermore, we show specific requirements of G4R1 for tight binding to telomeric DNA which are: 1) presence of G4-structure in the sequence and 2) a guanine-containing 3'-tail. Overall findings from this dissertation strongly suggest that G4R1 tightly and specifically binds to an exceptional array of G4-structures and could potentially serve as a \"pan\" G4-resolver in the cell. Indeed this finding could have significant genomic impact, as >375,000 G4-forming motifs exist in the genome and G4-structures have been shown to play prominent regulatory roles in transcription, translation, replication, immunoglobin switching, and telomere biology."],"dc:identifier.uri":["http://hdl.handle.net/10339/39141"],"dc:language.iso":["en"],"dc:publisher":["Wake Forest University"],"dc:subject":["dhx36"],"dc:title":["G4-RESOLVASE 1 TIGHTLY BINDS AND CATALYTICALLY UNWINDS UNIMOLECULAR G-QUADRUPLEX STRUCTURES WITH IMPLICATIONS FOR GENE TRANSCRIPTION AND TELOMERE BIOLOGY"],"dc:type":["Dissertation"]},"updated_at":"2026-07-27T22:01:39Z"}