Ticks are ectoparasites that attach to their host for many days to weeks, feeding to engorgement and continuing their species life cycle. The mechanisms behind the successful feeding and manipulation of host immune responses have been associated with the secretion of their specialized saliva. Tick saliva includes a variety of modulatory molecules that must disrupt and counteract defense mechanisms, including a variety of proteases. Reprolysin Metalloproteases, in the Zn2+ dependent family, is secreted as a proenzyme and is shown to have proteolytic activity, degrading fibrinogen and gelatinase activity, as well as disturbing homeostasis12. Previous work with the Amblyomma americanum sialotranscriptome identified over 40 metalloproteases secreted in the saliva during the ticks’ feeding. A. americanum is a carrier of multiple diseases, including Ehrlichia chaffeensis, the causative agent of Human Monocyte Ehrlichiosis. This experiment consisted of two main goals: the first was to characterize A. americanum Reprolysin Metalloproteases, and the second to gain a better insight into the relationship between this tick and E. chaffeensis, a pathogen very understudied within the tick vector and has proved problematic for animal model studies.
","abstract_html":"<p>Ticks are ectoparasites that attach to their host for many days to weeks, feeding to engorgement and continuing their species life cycle. The mechanisms behind the successful feeding and manipulation of host immune responses have been associated with the secretion of their specialized saliva. Tick saliva includes a variety of modulatory molecules that must disrupt and counteract defense mechanisms, including a variety of proteases. Reprolysin Metalloproteases, in the Zn<sup>2+</sup> dependent family, is secreted as a proenzyme and is shown to have proteolytic activity, degrading fibrinogen and gelatinase activity, as well as disturbing homeostasis<sup>1</sup><sup>2</sup>. Previous work with the <em>Amblyomma americanum</em> sialotranscriptome identified over 40 metalloproteases secreted in the saliva during the ticks’ feeding. <em>A. americanum</em> is a carrier of multiple diseases, including <em>Ehrlichia chaffeensis</em>, the causative agent of Human Monocyte Ehrlichiosis. This experiment consisted of two main goals: the first was to characterize <em>A. americanum</em> Reprolysin Metalloproteases, and the second to gain a better insight into the relationship between this tick and <em>E. chaffeensis</em>, a pathogen very understudied within the tick vector and has proved problematic for animal model studies.</p>","abstract_has_math":false,"creators":["Williams, Jaclyn Bo"],"institution":null,"degree_name":"Master of Science (MS)","degree_level":"Masters Thesis","degree_discipline":"Biological Sciences","degree_department":null,"school":null,"contributors":["Shahid Karim","Yanlin Guo","Mohammed Elasri"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2015,"date_issued":"2015-08-01T07:00:00Z","date_published":"2015-08-01T07:00:00Z","updated_at":"2026-07-24T05:44:34Z","subjects":["Biology","Entomology"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://aquila.usm.edu/masters_theses/138","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Shahid Karim","Yanlin Guo","Mohammed Elasri"]},{"key":"dc:creator","label":"Author","values":["Williams, Jaclyn Bo"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2015-06-29T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biological Sciences"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Masters Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science (MS)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Biology","Entomology"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://aquila.usm.edu/masters_theses/138"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Ticks are ectoparasites that attach to their host for many days to weeks, feeding to engorgement and continuing their species life cycle. The mechanisms behind the successful feeding and manipulation of host immune responses have been associated with the secretion of their specialized saliva. Tick saliva includes a variety of modulatory molecules that must disrupt and counteract defense mechanisms, including a variety of proteases. Reprolysin Metalloproteases, in the Zn2+ dependent family, is secreted as a proenzyme and is shown to have proteolytic activity, degrading fibrinogen and gelatinase activity, as well as disturbing homeostasis12. Previous work with the Amblyomma americanum sialotranscriptome identified over 40 metalloproteases secreted in the saliva during the ticks’ feeding. A. americanum is a carrier of multiple diseases, including Ehrlichia chaffeensis, the causative agent of Human Monocyte Ehrlichiosis. This experiment consisted of two main goals: the first was to characterize A. americanum Reprolysin Metalloproteases, and the second to gain a better insight into the relationship between this tick and E. chaffeensis, a pathogen very understudied within the tick vector and has proved problematic for animal model studies.
"]},{"key":"dc:title","label":"Title","values":["Elucidating the Molecular Function of Reprolysin Metalloproteases in Tick-Host-Pathogen Interaction"]}]}],"canonical_facts":{"dc:contributor":["Shahid Karim","Yanlin Guo","Mohammed Elasri"],"dc:creator":["Williams, Jaclyn Bo"],"dc:date.available":["2015-06-29T07:00:00Z"],"dc:description.abstract":["Ticks are ectoparasites that attach to their host for many days to weeks, feeding to engorgement and continuing their species life cycle. The mechanisms behind the successful feeding and manipulation of host immune responses have been associated with the secretion of their specialized saliva. Tick saliva includes a variety of modulatory molecules that must disrupt and counteract defense mechanisms, including a variety of proteases. Reprolysin Metalloproteases, in the Zn2+ dependent family, is secreted as a proenzyme and is shown to have proteolytic activity, degrading fibrinogen and gelatinase activity, as well as disturbing homeostasis12. Previous work with the Amblyomma americanum sialotranscriptome identified over 40 metalloproteases secreted in the saliva during the ticks’ feeding. A. americanum is a carrier of multiple diseases, including Ehrlichia chaffeensis, the causative agent of Human Monocyte Ehrlichiosis. This experiment consisted of two main goals: the first was to characterize A. americanum Reprolysin Metalloproteases, and the second to gain a better insight into the relationship between this tick and E. chaffeensis, a pathogen very understudied within the tick vector and has proved problematic for animal model studies.
"],"dc:identifier":["https://aquila.usm.edu/masters_theses/138"],"dc:subject":["Biology","Entomology"],"dc:title":["Elucidating the Molecular Function of Reprolysin Metalloproteases in Tick-Host-Pathogen Interaction"],"thesis:degree_discipline":["Biological Sciences"],"thesis:degree_level":["Masters Thesis"],"thesis:degree_name":["Master of Science (MS)"]},"updated_at":"2026-07-24T05:44:34Z"}