.
In mammalian cells, the role of clathrin and adaptor protein complexes (APs) in
endosomal and lysosomal protein delivery is well known. Unlike these cells, only AP1
and AP2 are present in the Giardia genome. We recently found that gAP1 participates
in lysosomal protein trafficking from a sorting organelle to the lysosomal-like
peripheral vacuoles (PVs) in Giardia, but the function of AP2 had not been elucidated.
Based on what was described for more evolved cells, we hypothesize that gAP2 is the
adaptor protein involved in vesicular trafficking from the plasma membrane to the PVs.
By using a specific antibody against one of the subunits of gAP2 (ì2), we showed that it
localizes in the PVs as well as close to the plasma membrane. To analyze the interaction
of gAP2 with associated proteins the YTH and CoIPP assays were performed.
Production of ì2 ds RNA for protein knock-down was used to study the role of gAP2 in
receptor-dependent and independent endocytic mechanisms. By using different
approaches we were able to observe that gAP2 is critical in trophozoite growth and
differentiation and that depletion of ì2 affects receptor-mediated endocytosis. The
complete characterization of gAP2 role would contribute to increase our knowledge
about this extremely simplified protein trafficking system present in this primitive
human parasite.
In mammalian cells, the role of clathrin and adaptor protein complexes (APs) in
endosomal and lysosomal protein delivery is well known. Unlike these cells, only AP1
and AP2 are present in the Giardia genome. We recently found that gAP1 participates
in lysosomal protein trafficking from a sorting organelle to the lysosomal-like
peripheral vacuoles (PVs) in Giardia, but the function of AP2 had not been elucidated.
Based on what was described for more evolved cells, we hypothesize that gAP2 is the
adaptor protein involved in vesicular trafficking from the plasma membrane to the PVs.
By using a specific antibody against one of the subunits of gAP2 (ì2), we showed that it
localizes in the PVs as well as close to the plasma membrane. To analyze the interaction
of gAP2 with associated proteins the YTH and CoIPP assays were performed.
Production of ì2 ds RNA for protein knock-down was used to study the role of gAP2 in
receptor-dependent and independent endocytic mechanisms. By using different
approaches we were able to observe that gAP2 is critical in trophozoite growth and
differentiation and that depletion of ì2 affects receptor-mediated endocytosis. The
complete characterization of gAP2 role would contribute to increase our knowledge
about this extremely simplified protein trafficking system present in this primitive
human parasite.
In mammalian cells, the role of clathrin and adaptor protein complexes (APs) in
endosomal and lysosomal protein delivery is well known. Unlike these cells, only AP1
and AP2 are present in the Giardia genome. We recently found that gAP1 participates
in lysosomal protein trafficking from a sorting organelle to the lysosomal-like
peripheral vacuoles (PVs) in Giardia, but the function of AP2 had not been elucidated.
Based on what was described for more evolved cells, we hypothesize that gAP2 is the
adaptor protein involved in vesicular trafficking from the plasma membrane to the PVs.
By using a specific antibody against one of the subunits of gAP2 (ì2), we showed that it
localizes in the PVs as well as close to the plasma membrane. To analyze the interaction
of gAP2 with associated proteins the YTH and CoIPP assays were performed.
Production of ì2 ds RNA for protein knock-down was used to study the role of gAP2 in
receptor-dependent and independent endocytic mechanisms. By using different
approaches we were able to observe that gAP2 is critical in trophozoite growth and
differentiation and that depletion of ì2 affects receptor-mediated endocytosis. The
complete characterization of gAP2 role would contribute to increase our knowledge
about this extremely simplified protein trafficking system present in this primitive
human parasite.
