Protein kinase A regulatory subunit isoforms regulate growth and differentiation in Mucor circinelloides: essential role of PKAR4.

A subunit of protein kinase a regulates growth and differentiation in the fungus Mucor circinelloides.

The cyclic AMP (cAMP)-dependent protein kinase A (PKA) signaling pathway plays a role in regulating development, growth, and virulence in a number of fungi. To determine whether PKA plays a similar function in zygomycete fungi, a mutant of Mucor circinelloides was generated that lacks pkaR1, one of the regulatory subunits of PKA. The mutant showed a reduction in growth and alterations in germin...

Mucor circinelloides Growth and Differentiation in the Fungus A Subunit of Protein Kinase A Regulates

Protein kinase A is involved in the control of morphology and branching during aerobic growth of Mucor circinelloides.

The cAMP signal transduction pathway controls many processes in fungi. The Mucor circinelloides pkaR and pkaC genes, encoding the regulatory (PKAR) and catalytic (PKAC) subunit of the cAMP-dependent protein kinase A (PKA), have been cloned recently. Expression analysis during the dimorphic shift and colony morphology suggested a role for PKAR in the control of morphology and branching. Here str...

PKA from Mucor circinelloides: model to study the role of linker I in the interaction between R and C subunits.

Protein kinase A from the fungus Mucor circinelloides shows high affinity interaction between regulatory (R) and catalytic (C) subunits. Its R subunit shows a differential presence of several acidic residues in linker I region, in the amino terminus. Mutants R1, lacking the N-terminal region, and R2, lacking the acidic cluster, were used to analyze its effect on the interaction with the C subun...

Calcineurin Plays Key Roles in the Dimorphic Transition and Virulence of the Human Pathogenic Zygomycete Mucor circinelloides

Many pathogenic fungi are dimorphic and switch between yeast and filamentous states. This switch alters host-microbe interactions and is critical for pathogenicity. However, in zygomycetes, whether dimorphism contributes to virulence is a central unanswered question. The pathogenic zygomycete Mucor circinelloides exhibits hyphal growth in aerobic conditions but switches to multi-budded yeast gr...