« Previous Abstract"Characterization of the key aroma compounds in Longjing tea using stir bar sorptive extraction (SBSE) combined with gas chromatography-mass spectrometry (GC-MS), gas chromatography-olfactometry (GC-O), odor activity value (OAV), and aroma recombination"    Next AbstractMating-type-specific and nonspecific PAK kinases play shared and divergent roles in Cryptococcus neoformans »

Mol Cell Biol

Title:		The G-protein beta subunit GPB1 is required for mating and haploid fruiting in Cryptococcus neoformans
Author(s):		Wang P; Perfect JR; Heitman J;
Address:		"Department of Genetics, Duke University Medical Center, Durham, North Carolina 27710, USA"
Journal Title:		Mol Cell Biol
Year:		2000
Volume:		20
Issue:		1
Page Number:		352 - 362
DOI:		10.1128/MCB.20.1.352-362.2000
ISSN/ISBN:		0270-7306 (Print) 1098-5549 (Electronic) 0270-7306 (Linking)
Abstract:		"Cryptococcus neoformans is an opportunistic fungal pathogen with a defined sexual cycle. The gene encoding a heterotrimeric G-protein beta subunit, GPB1, was cloned and disrupted. gpb1 mutant strains are sterile, indicating a role for this gene in mating. GPB1 plays an active role in mediating responses to pheromones in early mating steps (conjugation tube formation and cell fusion) and signals via a mitogen-activated protein (MAP) kinase cascade in both MATalpha and MATa cells. The functions of GPB1 are distinct from those of the Galpha protein GPA1, which functions in a nutrient-sensing cyclic AMP (cAMP) pathway required for mating, virulence factor induction, and virulence. gpb1 mutant strains are also defective in monokaryotic fruiting in response to nitrogen starvation. We show that MATa cells stimulate monokaryotic fruiting of MATalpha cells, possibly in response to mating pheromone, which may serve to disperse cells and spores to locate mating partners. In summary, the Gbeta subunit GPB1 and the Galpha subunit GPA1 function in distinct signaling pathways: one (GPB1) senses pheromones and regulates mating and haploid fruiting via a MAP kinase cascade, and the other (GPA1) senses nutrients and regulates mating, virulence factors, and pathogenicity via a cAMP cascade"
Keywords:		"Amino Acid Sequence Cryptococcus neoformans/*physiology Fungal Proteins/genetics *Gene Expression Regulation, Fungal Heterotrimeric GTP-Binding Proteins/*genetics MAP Kinase Signaling System/genetics Molecular Sequence Data *Schizosaccharomyces pombe Prot;"
Notes:		"MedlineWang, P Perfect, J R Heitman, J eng R37 AI039115/AI/NIAID NIH HHS/ R01 AI042159/AI/NIAID NIH HHS/ AI42159/AI/NIAID NIH HHS/ R01 AI039115/AI/NIAID NIH HHS/ R01 AI39115/AI/NIAID NIH HHS/ P01 AI44975/AI/NIAID NIH HHS/ P01 AI044975/AI/NIAID NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. 1999/12/14 Mol Cell Biol. 2000 Jan; 20(1):352-62. doi: 10.1128/MCB.20.1.352-362.2000"