Characterization of the  Paracoccidioides beta-1,3-glucanosyltransferase family.
The cell wall of pathogenic microbes acts as an initial barrier that is in contact with hostile environments. Several proteins are associated to the cell wall, including the glucanosyltransferases, which are attached through glycosylphosphatidylinositol anchors to the wall. Here, we characterized the Paracoccidioides beta-1,3-glucanosyltranferase ( Gel ) family of proteins that showed significant homology to proteins belonging to the GH72 family. Immunoassays demonstrated Gel1p associated with the cell wall and with the nucleus. For Gel2p, immune labeling was associated with the cell wall and cytoplasm. Genetic complementation studies in Saccharomyces cerevisiae demonstrated that Gel2p is able to participate in the maintenance of fungal cell wall integrity, as it was able to restore the lack of Gas1p activity in a gas1Δ mutant; Gel1p was not able to do the same. On the other hand, Gel1p restores telomeric silencing in a gas1Δ mutant, providing strong support that Gel1p can be involved in transcriptional silencing in Paracoccidioides. Use of the in vivo yeast two-hybrid system revealed proteins that interact with Paracoccidioides Gel proteins, supporting new insights into the function of Gel family members and suggesting that they could play other roles than those established at the fungal cell wall.
Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiás, Brazil.
Patrícia
P
de Sousa Lima
Elisa Flávia Luiz Cardoso
EF
Bailão
Mirelle Garcia
MG
Silva
Nadya da Silva
Nda S
Castro
Sônia Nair
SN
Báo
Ivan
I
Orlandi
Marina
M
Vai
Célia Maria
CM
de Almeida Soares
D002467:Cell Nucleus / Q000201:enzymology; D002473:Cell Wall / Q000201:enzymology; D003593:Cytoplasm / Q000201:enzymology; D017353:Gene Deletion; D005816:Genetic Complementation Test; D004693:Glucan Endo-1,3-beta-D-Glucosidase / Q000235:genetics / Q000378:metabolism*; D010228:Paracoccidioides / Q000201:enzymology* / Q000235:genetics; D025941:Protein Interaction Mapping; D017386:Sequence Homology, Amino Acid; D020798:Two-Hybrid System Techniques
C117939:1,3-beta-glucanosyltransferase; D004693:Glucan Endo-1,3-beta-D-Glucosidase