title: Genetic structure and expression of the surface glycoprotein GP82, the main adhesin of Trypanosoma cruzi metacyclic trypomastigotes.
abstract: T. cruzi improves the likelihood of invading or adapting to the host through its capacity to present a large repertoire of surface molecules. The metacyclic stage-specific surface glycoprotein GP82 has been implicated in host cell invasion. GP82 is encoded by multiple genes from the trans-sialidase superfamily. GP82 shows a modular organization, with some variation of N-terminal region flanking a conserved central core where the binding sites to the mammalian cell and gastric mucin are located. The function of GP82 as adhesin in host cell invasion process could expose the protein to an intense conservative and selective pressure. GP82 is a GPI-anchored surface protein, synthesized as a 70 kDa precursor devoid of N-linked sugars. GPI-minus variants accumulate in the ER indicating that GPI anchor acts as a forward transport signal for progressing along the secretory pathway as suggested for T. cruzi mucins. It has been demonstrated that the expression of GP82 is constitutive and may be regulated at post-transcriptional level, for instance, at translational level and/or mRNA stabilization. GP82 mRNAs are mobilized to polysomes and consequently translated, but only in metacyclic trypomastigotes. Analysis of transgenic parasites indicates that the mechanism regulating GP82 expression involves multiple elements in the 3'UTR.
authors: Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, Rua Botucatu 862, 04023-062 São Paulo, SP, Brazil.
authors: Paulo Roberto Ceridorio
authors: PR
authors: Correa
authors: Esteban Mauricio
authors: EM
authors: Cordero
authors: Luciana Girotto
authors: LG
authors: Gentil
authors: Ethel
authors: E
authors: Bayer-Santos
authors: José Franco
authors: JF
authors: da Silveira
mesh_terms: D020413:3' Untranslated Regions; D000595:Amino Acid Sequence; D001665:Binding Sites; D002448:Cell Adhesion; D014355:Chagas Disease / Q000469:parasitology; D005786:Gene Expression Regulation; D006801:Humans; D008969:Molecular Sequence Data; D005810:Multigene Family; D011132:Polyribosomes / Q000378:metabolism; D015800:Protozoan Proteins / Q000235:genetics* / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional; D020871:RNA Stability; D014349:Trypanosoma cruzi / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D014643:Variant Surface Glycoproteins, Trypanosoma / Q000235:genetics* / Q000378:metabolism*
chemical_list: D020413:3' Untranslated Regions; D015800:Protozoan Proteins; D014643:Variant Surface Glycoproteins, Trypanosoma; C527132:glycoprotein GP82, Trypanosoma cruzi