{"id":{"repo_id":"cape-town","oai_identifier":"oai:open.uct.ac.za:11427/4336"},"canonical_url":"https://search.dev.ndltd.org/etd/cape-town/oai:open.uct.ac.za:11427/4336","repository":{"repo_id":"cape-town","name":"University of Cape Town","base_url":"https://open.uct.ac.za/oai/request"},"display":{"title":"Targeted expression of the anti-HIV microbicide lectin griffithsin in maize and tobacco","abstract":"Plants are emerging as cost friendly alternative production systems for a variety of pharmaceuticals. Numerous therapeutic proteins have been produced in plant systems (Giddings et al., 2000; Ma et al., 2003). Protein based microbicides,-namely, neutralising antibodies and peptide lectins- lend themselves to production in plants (De Muynck et al., 2010; Matoba et al., 2010; Sexton et al. 2006; O’Keefe et al., 2009). One of these lectins, namely Griffithsin (GRFT) was isolated from the blue green algae Griffithsia and is being developed as a leading anti-HIV microbicide peptide (Mori et al., 2005). As literature indicates, the optimal production of any protein is an empirical experimentation with different host systems, vector systems, codon optimisations and subcellular targeting. (Maclean et al., 2007; Yang et al., 2005). The latter sometimes results in unexpected locations which might reflect on an inherent property of the protein itself or specifically be associated with the plant organ involved (Chikwamba et al., 2003). This again can influence protein yield- and activity, and impact downstream purification. In this study we aimed to compare expression levels using both Zea mays (maize) and Nicotiana benthamiana (tobacco) with relevant vector technologies. We expressed GRFT in maize using an endosperm specific maize expression vector with and without a signal peptide. In tobacco we utilised both the pTRA binary vector and magnICON deconstructed viral vector system to express GRFT with different subcellular targeting signals.","abstract_html":"Plants are emerging as cost friendly alternative production systems for a variety of pharmaceuticals. Numerous therapeutic proteins have been produced in plant systems (Giddings et al., 2000; Ma et al., 2003). Protein based microbicides,-namely, neutralising antibodies and peptide lectins- lend themselves to production in plants (De Muynck et al., 2010; Matoba et al., 2010; Sexton et al. 2006; O’Keefe et al., 2009). One of these lectins, namely Griffithsin (GRFT) was isolated from the blue green algae Griffithsia and is being developed as a leading anti-HIV microbicide peptide (Mori et al., 2005). As literature indicates, the optimal production of any protein is an empirical experimentation with different host systems, vector systems, codon optimisations and subcellular targeting. (Maclean et al., 2007; Yang et al., 2005). The latter sometimes results in unexpected locations which might reflect on an inherent property of the protein itself or specifically be associated with the plant organ involved (Chikwamba et al., 2003). This again can influence protein yield- and activity, and impact downstream purification. In this study we aimed to compare expression levels using both Zea mays (maize) and Nicotiana benthamiana (tobacco) with relevant vector technologies. We expressed GRFT in maize using an endosperm specific maize expression vector with and without a signal peptide. In tobacco we utilised both the pTRA binary vector and magnICON deconstructed viral vector system to express GRFT with different subcellular targeting signals.","abstract_has_math":false,"creators":["Stark, Hester Catharina (Therese)"],"institution":"Department of Molecular and Cell Biology","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Rybicki, Ed","Chikwamba, Rachel"],"committee_chairs":[],"committee_members":[],"year":2013,"date_issued":"2013","date_published":"2013","updated_at":"2026-07-22T22:23:23Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11427/4336","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Rybicki, Ed","Chikwamba, Rachel"]},{"key":"dc:creator","label":"Author","values":["Stark, Hester Catharina (Therese)"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-07-30T17:41:59Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-07-30T17:41:59Z"]},{"key":"dc:date.issued","label":"Date","values":["2013"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Molecular and Cell Biology"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cape Town"]},{"key":"dc:type","label":"Dc Type","values":["Doctoral Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["PhD"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11427/4336"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Includes abstract.","Includes bibliographical references."]},{"key":"dc:description.abstract","label":"Abstract","values":["Plants are emerging as cost friendly alternative production systems for a variety of pharmaceuticals. Numerous therapeutic proteins have been produced in plant systems (Giddings et al., 2000; Ma et al., 2003). Protein based microbicides,-namely, neutralising antibodies and peptide lectins- lend themselves to production in plants (De Muynck et al., 2010; Matoba et al., 2010; Sexton et al. 2006; O’Keefe et al., 2009). One of these lectins, namely Griffithsin (GRFT) was isolated from the blue green algae Griffithsia and is being developed as a leading anti-HIV microbicide peptide (Mori et al., 2005). As literature indicates, the optimal production of any protein is an empirical experimentation with different host systems, vector systems, codon optimisations and subcellular targeting. (Maclean et al., 2007; Yang et al., 2005). The latter sometimes results in unexpected locations which might reflect on an inherent property of the protein itself or specifically be associated with the plant organ involved (Chikwamba et al., 2003). This again can influence protein yield- and activity, and impact downstream purification. In this study we aimed to compare expression levels using both Zea mays (maize) and Nicotiana benthamiana (tobacco) with relevant vector technologies. We expressed GRFT in maize using an endosperm specific maize expression vector with and without a signal peptide. In tobacco we utilised both the pTRA binary vector and magnICON deconstructed viral vector system to express GRFT with different subcellular targeting signals."]},{"key":"dc:title","label":"Title","values":["Targeted expression of the anti-HIV microbicide lectin griffithsin in maize and tobacco"]}]}],"canonical_facts":{"dc:contributor.advisor":["Rybicki, Ed","Chikwamba, Rachel"],"dc:creator":["Stark, Hester Catharina (Therese)"],"dc:date.accessioned":["2014-07-30T17:41:59Z"],"dc:date.available":["2014-07-30T17:41:59Z"],"dc:date.issued":["2013"],"dc:description":["Includes abstract.","Includes bibliographical references."],"dc:description.abstract":["Plants are emerging as cost friendly alternative production systems for a variety of pharmaceuticals. Numerous therapeutic proteins have been produced in plant systems (Giddings et al., 2000; Ma et al., 2003). Protein based microbicides,-namely, neutralising antibodies and peptide lectins- lend themselves to production in plants (De Muynck et al., 2010; Matoba et al., 2010; Sexton et al. 2006; O’Keefe et al., 2009). One of these lectins, namely Griffithsin (GRFT) was isolated from the blue green algae Griffithsia and is being developed as a leading anti-HIV microbicide peptide (Mori et al., 2005). As literature indicates, the optimal production of any protein is an empirical experimentation with different host systems, vector systems, codon optimisations and subcellular targeting. (Maclean et al., 2007; Yang et al., 2005). The latter sometimes results in unexpected locations which might reflect on an inherent property of the protein itself or specifically be associated with the plant organ involved (Chikwamba et al., 2003). This again can influence protein yield- and activity, and impact downstream purification. In this study we aimed to compare expression levels using both Zea mays (maize) and Nicotiana benthamiana (tobacco) with relevant vector technologies. We expressed GRFT in maize using an endosperm specific maize expression vector with and without a signal peptide. In tobacco we utilised both the pTRA binary vector and magnICON deconstructed viral vector system to express GRFT with different subcellular targeting signals."],"dc:identifier.uri":["http://hdl.handle.net/11427/4336"],"dc:language.iso":["eng"],"dc:publisher.department":["Department of Molecular and Cell Biology"],"dc:publisher.institution":["University of Cape Town"],"dc:title":["Targeted expression of the anti-HIV microbicide lectin griffithsin in maize and tobacco"],"dc:type":["Doctoral Thesis"],"dc:type.qualificationlevel":["Doctoral"],"dc:type.qualificationname":["PhD"]},"updated_at":"2026-07-22T22:23:23Z"}