{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,16]],"date-time":"2026-05-16T12:47:28Z","timestamp":1778935648567,"version":"3.51.4"},"reference-count":53,"publisher":"The Company of Biologists","issue":"19","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2010,10,1]]},"abstract":"<jats:p>Trypanosomes evade host immunity by exchanging variant surface glycoprotein (VSG) coats. VSG genes are transcribed from telomeric expression sites, which contain a diverse family of expression-site-associated genes (ESAGs). We have discovered that the mRNAs for one ESAG family, ESAG9, are strongly developmentally regulated, being enriched in stumpy forms, a life-cycle stage in the mammalian bloodstream that is important for the maintenance of chronic parasite infections and for tsetse transmission. ESAG9 gene sequences are highly diverse in the genome and encode proteins with weak similarity to the massively diverse MASP proteins in Trypanosoma cruzi. We demonstrate that ESAG9 proteins are modified by N-glycosylation and can be shed to the external milieu, this being dependent upon coexpression with at least one other family member. The expression profile and extracellular release of ESAG9 proteins represents a novel and unexpected aspect of the transmission biology of trypanosomes in their mammalian host. We suggest that these molecules might interact with the external environment, with possible implications for infection chronicity or parasite transmission.<\/jats:p>","DOI":"10.1242\/jcs.068684","type":"journal-article","created":{"date-parts":[[2010,9,9]],"date-time":"2010-09-09T00:19:46Z","timestamp":1283991586000},"page":"3401-3411","source":"Crossref","is-referenced-by-count":19,"title":["Developmental regulation and extracellular release of a <i>VSG<\/i> expression-site-associated gene product from <i>Trypanosoma brucei<\/i> bloodstream forms"],"prefix":"10.1242","volume":"123","author":[{"given":"Eleanor M.","family":"Barnwell","sequence":"first","affiliation":[{"name":"Centre for Immunity, Infection and Evolution, Institute of Immunology and Infection Research, School of Biological Sciences, Kings' Buildings, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Frederick J.","family":"van Deursen","sequence":"additional","affiliation":[{"name":"Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Wilmslow Road, Manchester M20 4BX, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laura","family":"Jeacock","sequence":"additional","affiliation":[{"name":"Centre for Immunity, Infection and Evolution, Institute of Immunology and Infection Research, School of Biological Sciences, Kings' Buildings, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Katherine A.","family":"Smith","sequence":"additional","affiliation":[{"name":"Centre for Immunity, Infection and Evolution, Institute of Immunology and Infection Research, School of Biological Sciences, Kings' Buildings, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rick M.","family":"Maizels","sequence":"additional","affiliation":[{"name":"Centre for Immunity, Infection and Evolution, Institute of Immunology and Infection Research, School of Biological Sciences, Kings' Buildings, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alvaro","family":"Acosta-Serrano","sequence":"additional","affiliation":[{"name":"Vector Group, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Keith","family":"Matthews","sequence":"additional","affiliation":[{"name":"Centre for Immunity, Infection and Evolution, Institute of Immunology and Infection Research, School of Biological Sciences, Kings' Buildings, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"237","reference":[{"key":"2021042521154859800_R1","doi-asserted-by":"crossref","first-page":"987","DOI":"10.1038\/nature07067","article-title":"Self-destructive cooperation mediated by phenotypic noise","volume":"454","author":"Ackermann","year":"2008","journal-title":"Nature"},{"key":"2021042521154859800_R2","doi-asserted-by":"crossref","first-page":"1537","DOI":"10.1128\/IAI.74.3.1537-1546.2006","article-title":"Molecular characterization of serine-, alanine-, and proline-rich proteins of Trypanosoma cruzi and their possible role in host cell infection","volume":"74","author":"Baida","year":"2006","journal-title":"Infect. 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