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Of the two, CaRas1 is mainly required by C. albicans to switch from its yeast to hyphal form, a process that is critical for the organism to establish invasive systemic infections. On the contrary, CaRas2 appears to function in antagonism to CaRas1 in several cellular processes. The closely related human pathogenic fungus, C. albicans, also has two Ras proteins, but they are not functionally redundant. S. cerevisiae has two Ras proteins, ScRas1 and ScRas2, which are highly homologous and functionally redundant, sharing around 90% similarity in sequence but differing in their transcriptional regulation. Several insights that have been gained about Ras proteins in the mammalian system, for example, have depended on what has been learned from the S. cerevisiae system. Such is the degree of conservation amongst this family of proteins that S. cerevisiae Ras proteins have often been used as models for the study of homologs from other organisms. Thus, they are the crucial hub of many cellular signaling pathways. In the GTP-bound state, Ras proteins can interact with numerous effector proteins depending on the presence of Ras association or Ras binding domains in them to transduce downstream a signal that is received either directly from the extracellular environment or from an upstream interacting partner. Their ability to participate in such a diverse set of events is dependent on their ability to act as molecular switches, cycling between an inactive GDP-bound form and an active GTP-bound form. Ras proteins are highly conserved small GTPases that participate in a wide variety of functions of the eukaryotic cell including survival, proliferation, differentiation, morphogenesis, and gene expression. This effect too is specific to CaRas1 and ScRas2 is unable to replicate it. This has direct consequences for expression of CaERG11, encoding the target of azole antifungals. In turn, CaGPI2 downregulates CaGPI19, encoding another GPI-GnT subunit. Interestingly, CaRas1 transcriptionally activates CaGPI2, encoding a GPI-GnT subunit that has been shown to interact with CaRas1 physically. That CaRas1 alone activates GPI-GnT and not ScRas2 suggests that this process is cAMP independent. However, ScRas2 is unable to activate the GPI- N -acetylglucosaminyl transferase (GPI-GnT) which catalyzes the first step of GPI biosynthesis. We show that ScRas2 functionally complements CaRas1 in rescuing growth as well as activating hyphal growth, a process that involves plasma membrane localized Ras activating cAMP/PKA signaling via Cyr1. In order to understand how extensive is the functional homology between the highly homologous proteins, S. cerevisiae Ras2 and C. albicans Ras1, we examined whether ScRas2 could functionally complement CaRas1 in activating hyphal morphogenesis as well as GPI anchor biosynthesis. GTP-bound Ras binds to effectors to trigger signaling cascades. Ras proteins are highly conserved small GTPases in eukaryotes.