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A immune-response molecule which limits trypanosome infection of tsetse midguts. Mike Lehane Liverpool School of Tropical Medicine. Midgut establishment. 1. Complex differentiation to asymmetric dividing epimastigote + migration. 2. T. brucei development in the tsetse fly. 3.
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A immune-response molecule which limits trypanosome infection of tsetse midguts. Mike Lehane Liverpool School of Tropical Medicine
Midgut establishment 1. Complex differentiation to asymmetric dividing epimastigote+ migration 2. T. brucei development in the tsetse fly 3. Metacyclogenesis
Cardia Salivary Gland Midgut Successful infection
Mean +/- S.E.M. % trypanosome prevalence 1st 2nd 3rd 4th >90% of laboratory midgut Infections fail Midgut infection success rates 70 10 30+ Blood meal
The fly immune system affects trypanosome establishment in the midgut NS NSNS P<.0.01 P< 0.05 Trypanosome prevalence PBS LPSE.coli M.luteusPTG Laminarin
Glossina gene discovery (EST programs) Head library and fat body library will soon be available within GeneDB making the EST much more useful to the research community LSTM, Sanger, Yale and TIGR
Injection of : 1. Gmm2412 dsRNA 2. Ampicillin dsRNA 3. PBS 1 2 3 Gmm2412 GAPDH Development of suitable tools (RNAi) Injection of : 1. Gmm2412 dsRNA 2. NFW Injection of : 1. TsetseEP dsRNA 2. NFW 3. non-injected 1 2 Gmm2412 GAPDH 1 2 3 TsetseEP GAPDH
Trypanosoma brucei EPprocyclin TsetseEP
Trypanosome prevalence following knockdown (RNAi) of tsetseEP
Is TsetseEP immune responsive? • 2D gels of midgut protein: • A. 3 days post injection with PBS • B. 3 days post injection with live E. coli K12RM148
TsetseEP is present in all tsetse species investigated and is unique to Glossina. savannah riverine forest G. palpalis
Summary • The tsetse fly immune response molecule TsetseEP affects the ability of trypanosomes to become established in the midgut of tsetse flies.
LSTM • Lee Haines • Stella Lehane • Deidre Walshe • UVIC • Terry Pearson • Bristol • Wendy Gibson • Lori Peacock • Yale • Serap Aksoy • Sanger • Matt Berriman • TIGR / Liverpool • Neil Hall
Candidate GenesMidgut lectins21 genes with carbohydrate recognition domains in EST libraries. • Gmm2412 cType signal sequence • Gmm3236 cType signal sequence • Gmm9056 galectin no-signal sequence • TsetseEP M. Chandra, M. Liniger, L. Tetley, I. Roditi, J. D. Barry, Insect Biochemistry And Molecular Biology 34, 1163 (Nov, 2004).
Trypanosome prevalence following knockdown (RNAi) of Lectins Gmm2412 no effect Gmm3236 no effect Gmm9056 no effect
Trypanosome prevalence following knockdown (RNAi) of Lectins TsetseEP strong effect
Trypanosoma brucei EPprocyclin Trypanosoma congolense GARPprocyclin MTTTMSRVLHLMTVTLLCARVGMGQASDDDDCGGQSIPQKVEEVQTMCD VVQQLRALETASQSAVASVVAFAREASEAKERAEKAVERAKSKKRGVDAA TEAAARATAAAQRAETVVSDARKHAADLTAASKDAIETADESLRLLATCEKA DEPIRTAAEKCTGAAAEVTSKSLESAFDALAELLPDGADEIREHGAVFVVGLK SLEDDV RTAGEAKSEAEKAEGDANDAADGARAVLTGVCVLLLLAALH
Binding to the trypanosome surface? TsetseEP Antibody X
Does TsetseEP knockdown affect the prevalence of T. congolense?