| K. Y. Hwa and P. T. Englund |
------>authors3_c=None ------>paper_class1=2 ------>Impact_Factor=None ------>paper_class3=0 ------>paper_class2=0 ------>vol= ------>confirm_bywho= ------>insert_bywho=kyhwa ------>Jurnal_Rank=None ------>authors4_c=None ------>comm_author= ------>patent_EDate=None ------>authors5_c=None ------>publish_day=None ------>paper_class2Letter=None ------>page2= ------>medlineContent= ------>unit=000 ------>insert_date=20020321 ------>iam=1 ------>update_date= ------>author=??? ------>change_event=1 ------>ISSN=None ------>authors_c=None ------>score=135 ------>journal_name=Molecular Parasitology Meeting ------>paper_name=Lectin resistant mutants in Trypanosoma brucei ------>confirm_date= ------>tch_id=090057 ------>pmid=11099385 ------>page1= ------>fullAbstract=Concanavalin A (Con A) kills procyclic (insect) forms of Trypanosoma brucei by binding to N-glycans on EP-procyclin, a major surface glycosyl phosphatidylinositol (GPI)-anchored protein which is rich in Glu-Pro repeats. We have previously isolated and studied two procyclic mutants (ConA 1-1 and ConA 4-1) that are more resistant than wild-type (WT) to Con A killing. Although both mutants express the same altered oligosaccharides compared to WT cells, ConA 4-1 is considerably more resistant to lectin killing than is ConA 1-1. Thus, we looked for other alterations to account for the differences in sensitivity. Using mass spectrometry, together with chemical and enzymatic treatments, we found that both mutants express types of EP-procyclin that are either poorly expressed or not found at all in WT cells. ConA 1-1 expresses mainly EP1-3, a novel procyclin that contains 18 EP repeats, is partially N-glycosylated, and bears hybrid-type glycans. On the other hand, ConA 4-1 cells express almost exclusively EP2-3, a novel non-glycosylated procyclin isoform with 23 EP repeats and no site for glycosylation. The predominance of EP2-3 in ConA 4-1 cells explains their high resistance to ConA killing. Thus, switching the procyclin repertoire, a process that could be relevant to parasite development in the insect vector, modulates the sensitivity of trypanosomes to cytotoxic lectins. ------>tmu_sno=None ------>sno=4948 ------>authors2=None ------>authors3=None ------>authors4=None ------>authors5=None ------>authors6=None ------>authors6_c=None ------>authors=K. Y. Hwa and P. T. Englund ------>delete_flag=0 ------>SCI_JNo=None ------>authors2_c=None ------>publish_area=None ------>updateTitle=Killing of Trypanosoma brucei by concanavalin A: structural basis of resistance in glycosylation mutants. ------>language=2 ------>check_flag= ------>submit_date= ------>country=None ------>no= ------>patent_SDate=None ------>update_bywho= ------>publish_year=1995 ------>submit_flag= ------>publish_month=None |