INVESTIGADORES
MORENO Silvia Margarita
artículos
Título:
Mucor rouxii Rho1 protein; characterization and possible role in polarized growth
Autor/es:
ARGIMÓN, S., GALELLO, F., PEREYRA, E., ROSSI, S. AND MORENO, S.
Revista:
ANTON LEEUW INT. J. G.
Referencias:
Año: 2007 vol. 91 p. 237 - 251
ISSN:
0003-6072
Resumen:
Abstract We have previously shown that protein kinase A of the medically important zygomyceteWe have previously shown that protein kinase A of the medically important zygomycete Mucor rouxii participates in fungal morphology through cytoskeletal organization. As a first step towards finding the link between protein kinase A and cytoskeletal organization we here demonstrate the cloning of the RHO1 gene and the characterization of its protein product. The Rho1 protein primary sequence shows 70–85% identity with fungal RHO1 or mammalian RhoA. Two protein kinase A phosphorylation sequences in adequate context are predicted, Ser73 and Ser135. The peptide IRRNSQKFV, containing Ser135 proved to be a good substrate for M. rouxii protein kinase A catalytic subunit. The over-expressed Rho1 fully complements a Saccharomyces cerevisiaeparticipates in fungal morphology through cytoskeletal organization. As a first step towards finding the link between protein kinase A and cytoskeletal organization we here demonstrate the cloning of the RHO1 gene and the characterization of its protein product. The Rho1 protein primary sequence shows 70–85% identity with fungal RHO1 or mammalian RhoA. Two protein kinase A phosphorylation sequences in adequate context are predicted, Ser73 and Ser135. The peptide IRRNSQKFV, containing Ser135 proved to be a good substrate for M. rouxii protein kinase A catalytic subunit. The over-expressed Rho1 fully complements a Saccharomyces cerevisiaeRHO1 gene and the characterization of its protein product. The Rho1 protein primary sequence shows 70–85% identity with fungal RHO1 or mammalian RhoA. Two protein kinase A phosphorylation sequences in adequate context are predicted, Ser73 and Ser135. The peptide IRRNSQKFV, containing Ser135 proved to be a good substrate for M. rouxii protein kinase A catalytic subunit. The over-expressed Rho1 fully complements a Saccharomyces cerevisiaeRHO1 or mammalian RhoA. Two protein kinase A phosphorylation sequences in adequate context are predicted, Ser73 and Ser135. The peptide IRRNSQKFV, containing Ser135 proved to be a good substrate for M. rouxii protein kinase A catalytic subunit. The over-expressed Rho1 fully complements a Saccharomyces cerevisiaeM. rouxii protein kinase A catalytic subunit. The over-expressed Rho1 fully complements a Saccharomyces cerevisiaeSaccharomyces cerevisiae null mutant. The endogenous protein was identified by western blot against a developed antibody and by ADP-ribosylation. Localization in germlings was visualized by immunofluorescence; the protein was localized in patches in the mother cell surface and excluded from the germ tube. Measurement of Rho1 expression during germination indicates that Rho1, at both the mRNA and protein levels, correlates with differentiation and not with growth. Rho1 has been shown to be the regulatory protein of the b-1,3- glucan synthase complex in fungi in which b-1,3- glucans are major components of the cell wall. Even though glucans have not been detected in zygomycetes, caspofungin, an echinochandin known to be an inhibitor of b-1,3-glucan synthase complex, is shown here to have a negative effect on growth and to produce an alteration on morphology when added to M. rouxii growth culture medium. This result has an important impact on the possible participation of b-1,3-glucans on the regulation of morphology of zygomycetes.b-1,3- glucan synthase complex in fungi in which b-1,3- glucans are major components of the cell wall. Even though glucans have not been detected in zygomycetes, caspofungin, an echinochandin known to be an inhibitor of b-1,3-glucan synthase complex, is shown here to have a negative effect on growth and to produce an alteration on morphology when added to M. rouxii growth culture medium. This result has an important impact on the possible participation of b-1,3-glucans on the regulation of morphology of zygomycetes.b-1,3- glucans are major components of the cell wall. Even though glucans have not been detected in zygomycetes, caspofungin, an echinochandin known to be an inhibitor of b-1,3-glucan synthase complex, is shown here to have a negative effect on growth and to produce an alteration on morphology when added to M. rouxii growth culture medium. This result has an important impact on the possible participation of b-1,3-glucans on the regulation of morphology of zygomycetes.b-1,3-glucan synthase complex, is shown here to have a negative effect on growth and to produce an alteration on morphology when added to M. rouxii growth culture medium. This result has an important impact on the possible participation of b-1,3-glucans on the regulation of morphology of zygomycetes.M. rouxii growth culture medium. This result has an important impact on the possible participation of b-1,3-glucans on the regulation of morphology of zygomycetes.b-1,3-glucans on the regulation of morphology of zygomycetes.