{"id":{"repo_id":"ku","oai_identifier":"oai:kuscholarworks.ku.edu:1808/4113"},"canonical_url":"https://search.dev.ndltd.org/etd/ku/oai:kuscholarworks.ku.edu:1808/4113","repository":{"repo_id":"ku","name":"University of Kansas","base_url":"https://kuscholarworks.ku.edu/server/oai/request"},"display":{"title":"Cloning and characterization of exc-9, a Caenorhabditis elegans CRIP homologue that regulates tubular structure","abstract":"Forming and maintaining tubular structure is fundamental to organismal development. The excretory canal cell of C.elegans forms a single-cell epithelial tubule, which provides a simple model for tubular structure study. The EXC proteins regulate maintenance of the apical (lumenal) cytoskeleton of the excretory canal. Loss of exc gene function allows formation of fluid-filled cysts in the excretory canal. exc-9 mutants exhibit short and cystic canals compared to wild-type worms. exc-9 mutants also exhibit tail defects in hermaphrodites and ray defects in male. By SNP mapping, cosmid rescue, and RNAi experiments, we proved that F20D12.5 encodes exc-9. EXC-9 is a homologue of the mammalian intestinal LIM-domain protein CRIP. exc-9 is highly expressed in the canal and tailspike, it is also expressed in some other cells, including UTSE, DTCs, and ALM neurons. Promoter regions important for exc-9 expression were studied. It was found that EXC-9 functions cell-autonomously and the free N-terminus of the protein is required for unextended canal phenotype. Overexpression of exc-9 constructs in an N2 background sometimes causes an \"unextended canal\" phenotype, in which the canal forms a large cell body filled with lumen with proper diameter, but has no canals along the length of the animal. Since canal extension is sensitive to expression levels of exc-9, injection of the construct also caused unextended canal phenotype in exc-9 mutants. Similar unextended canal phenotype was also found in animals showing high levels of exc-5 expression. I used the unextended canal phenotype to examine epistasis of EXC-9 function with that of other EXC proteins. EXC-9 appears to function upstream of EXC-5 to regulate cytoskeletal formation at the apical surface (possibly via CDC-42); and EXC-9 in turn may depend upon EXC-2 and EXC-4 function. A second well conserved CRIP homologue B0496.7 is highly expressed in multiple valves of C.elegans. It functions similarly to EXC-9 when ectopically expressed in the excretory canal. Expression of the mouse homologue CRIP in the canal failed to rescue exc-9 mutants, but with some modifications, mouse CRIP can function similar as EXC-9. Preliminary data of cloning of exc-2 is reported in this work too.","abstract_html":"Forming and maintaining tubular structure is fundamental to organismal development. The excretory canal cell of C.elegans forms a single-cell epithelial tubule, which provides a simple model for tubular structure study. The EXC proteins regulate maintenance of the apical (lumenal) cytoskeleton of the excretory canal. Loss of exc gene function allows formation of fluid-filled cysts in the excretory canal. exc-9 mutants exhibit short and cystic canals compared to wild-type worms. exc-9 mutants also exhibit tail defects in hermaphrodites and ray defects in male. By SNP mapping, cosmid rescue, and RNAi experiments, we proved that F20D12.5 encodes exc-9. EXC-9 is a homologue of the mammalian intestinal LIM-domain protein CRIP. exc-9 is highly expressed in the canal and tailspike, it is also expressed in some other cells, including UTSE, DTCs, and ALM neurons. Promoter regions important for exc-9 expression were studied. It was found that EXC-9 functions cell-autonomously and the free N-terminus of the protein is required for unextended canal phenotype. Overexpression of exc-9 constructs in an N2 background sometimes causes an "unextended canal" phenotype, in which the canal forms a large cell body filled with lumen with proper diameter, but has no canals along the length of the animal. Since canal extension is sensitive to expression levels of exc-9, injection of the construct also caused unextended canal phenotype in exc-9 mutants. Similar unextended canal phenotype was also found in animals showing high levels of exc-5 expression. I used the unextended canal phenotype to examine epistasis of EXC-9 function with that of other EXC proteins. EXC-9 appears to function upstream of EXC-5 to regulate cytoskeletal formation at the apical surface (possibly via CDC-42); and EXC-9 in turn may depend upon EXC-2 and EXC-4 function. A second well conserved CRIP homologue B0496.7 is highly expressed in multiple valves of C.elegans. It functions similarly to EXC-9 when ectopically expressed in the excretory canal. Expression of the mouse homologue CRIP in the canal failed to rescue exc-9 mutants, but with some modifications, mouse CRIP can function similar as EXC-9. Preliminary data of cloning of exc-2 is reported in this work too.","abstract_has_math":false,"creators":["Tong, Xiangyan"],"institution":"University of Kansas","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Buechner, Matthew J."],"committee_chairs":[],"committee_members":[],"year":2007,"date_issued":"2007-10-12","date_published":"2007-10-12","updated_at":"2026-07-24T02:46:17Z","subjects":["Molecular biology"],"languages":["EN"],"rights":["This item is protected by copyright and unless otherwise specified the copyright of this thesis/dissertation is held by the author."],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["http://dissertations.umi.com/ku:2199"],"render_values":[{"text":"http://dissertations.umi.com/ku:2199","href":"http://dissertations.umi.com/ku:2199","code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/1808/4113","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Buechner, Matthew J."]},{"key":"dc:creator","label":"Author","values":["Tong, Xiangyan"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2008-09-07T23:58:08Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2008-09-07T23:58:08Z"]},{"key":"dc:date.issued","label":"Date","values":["2007-10-12"]},{"key":"dc:publisher","label":"Institution","values":["University of Kansas"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Molecular biology"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["EN"]},{"key":"dc:rights","label":"Dc Rights","values":["This item is protected by copyright and unless otherwise specified the copyright of this thesis/dissertation is held by the author."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["http://dissertations.umi.com/ku:2199"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/1808/4113"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Forming and maintaining tubular structure is fundamental to organismal development. The excretory canal cell of C.elegans forms a single-cell epithelial tubule, which provides a simple model for tubular structure study. The EXC proteins regulate maintenance of the apical (lumenal) cytoskeleton of the excretory canal. Loss of exc gene function allows formation of fluid-filled cysts in the excretory canal. exc-9 mutants exhibit short and cystic canals compared to wild-type worms. exc-9 mutants also exhibit tail defects in hermaphrodites and ray defects in male. By SNP mapping, cosmid rescue, and RNAi experiments, we proved that F20D12.5 encodes exc-9. EXC-9 is a homologue of the mammalian intestinal LIM-domain protein CRIP. exc-9 is highly expressed in the canal and tailspike, it is also expressed in some other cells, including UTSE, DTCs, and ALM neurons. Promoter regions important for exc-9 expression were studied. It was found that EXC-9 functions cell-autonomously and the free N-terminus of the protein is required for unextended canal phenotype. Overexpression of exc-9 constructs in an N2 background sometimes causes an \"unextended canal\" phenotype, in which the canal forms a large cell body filled with lumen with proper diameter, but has no canals along the length of the animal. Since canal extension is sensitive to expression levels of exc-9, injection of the construct also caused unextended canal phenotype in exc-9 mutants. Similar unextended canal phenotype was also found in animals showing high levels of exc-5 expression. I used the unextended canal phenotype to examine epistasis of EXC-9 function with that of other EXC proteins. EXC-9 appears to function upstream of EXC-5 to regulate cytoskeletal formation at the apical surface (possibly via CDC-42); and EXC-9 in turn may depend upon EXC-2 and EXC-4 function. A second well conserved CRIP homologue B0496.7 is highly expressed in multiple valves of C.elegans. It functions similarly to EXC-9 when ectopically expressed in the excretory canal. Expression of the mouse homologue CRIP in the canal failed to rescue exc-9 mutants, but with some modifications, mouse CRIP can function similar as EXC-9. Preliminary data of cloning of exc-2 is reported in this work too."]},{"key":"dc:title","label":"Title","values":["Cloning and characterization of exc-9, a Caenorhabditis elegans CRIP homologue that regulates tubular structure"]}]}],"canonical_facts":{"dc:contributor.advisor":["Buechner, Matthew J."],"dc:creator":["Tong, Xiangyan"],"dc:date.accessioned":["2008-09-07T23:58:08Z"],"dc:date.available":["2008-09-07T23:58:08Z"],"dc:date.issued":["2007-10-12"],"dc:description.abstract":["Forming and maintaining tubular structure is fundamental to organismal development. The excretory canal cell of C.elegans forms a single-cell epithelial tubule, which provides a simple model for tubular structure study. The EXC proteins regulate maintenance of the apical (lumenal) cytoskeleton of the excretory canal. Loss of exc gene function allows formation of fluid-filled cysts in the excretory canal. exc-9 mutants exhibit short and cystic canals compared to wild-type worms. exc-9 mutants also exhibit tail defects in hermaphrodites and ray defects in male. By SNP mapping, cosmid rescue, and RNAi experiments, we proved that F20D12.5 encodes exc-9. EXC-9 is a homologue of the mammalian intestinal LIM-domain protein CRIP. exc-9 is highly expressed in the canal and tailspike, it is also expressed in some other cells, including UTSE, DTCs, and ALM neurons. Promoter regions important for exc-9 expression were studied. It was found that EXC-9 functions cell-autonomously and the free N-terminus of the protein is required for unextended canal phenotype. Overexpression of exc-9 constructs in an N2 background sometimes causes an \"unextended canal\" phenotype, in which the canal forms a large cell body filled with lumen with proper diameter, but has no canals along the length of the animal. Since canal extension is sensitive to expression levels of exc-9, injection of the construct also caused unextended canal phenotype in exc-9 mutants. Similar unextended canal phenotype was also found in animals showing high levels of exc-5 expression. I used the unextended canal phenotype to examine epistasis of EXC-9 function with that of other EXC proteins. EXC-9 appears to function upstream of EXC-5 to regulate cytoskeletal formation at the apical surface (possibly via CDC-42); and EXC-9 in turn may depend upon EXC-2 and EXC-4 function. A second well conserved CRIP homologue B0496.7 is highly expressed in multiple valves of C.elegans. It functions similarly to EXC-9 when ectopically expressed in the excretory canal. Expression of the mouse homologue CRIP in the canal failed to rescue exc-9 mutants, but with some modifications, mouse CRIP can function similar as EXC-9. Preliminary data of cloning of exc-2 is reported in this work too."],"dc:identifier.other":["http://dissertations.umi.com/ku:2199"],"dc:identifier.uri":["http://hdl.handle.net/1808/4113"],"dc:language.iso":["EN"],"dc:publisher":["University of Kansas"],"dc:rights":["This item is protected by copyright and unless otherwise specified the copyright of this thesis/dissertation is held by the author."],"dc:subject":["Molecular biology"],"dc:title":["Cloning and characterization of exc-9, a Caenorhabditis elegans CRIP homologue that regulates tubular structure"],"dc:type":["Dissertation"]},"updated_at":"2026-07-24T02:46:17Z"}