scholarly journals Pseudohyphal differentiation in Komagataella phaffii: investigating the FLO gene family

2020 ◽  
Vol 20 (5) ◽  
Author(s):  
Sonakshi De ◽  
Corinna Rebnegger ◽  
Josef Moser ◽  
Nadine Tatto ◽  
Alexandra B Graf ◽  
...  
Keyword(s):  
Gene Family ◽  
Nitrogen Starvation ◽  
Slow Growth ◽  
Transcriptional Analysis ◽  
Glucose Limitation ◽  
Pseudohyphal Growth ◽  
Komagataella Phaffii ◽  
Fusel Alcohols ◽  
Adverse Environmental Conditions ◽  
Pseudohyphal Differentiation

ABSTRACT Many yeasts differentiate into multicellular phenotypes in adverse environmental conditions. Here, we investigate pseudohyphal growth in Komagataella phaffii and the involvement of the flocculin (FLO) gene family in its regulation. The K. phaffii FLO family consists of 13 members, and the conditions inducing pseudohyphal growth are different from Saccharomyces cerevisiae. So far, this phenotype was only observed when K. phaffii was cultivated at slow growth rates in glucose-limited chemostats, but not upon nitrogen starvation or the presence of fusel alcohols. Transcriptional analysis identified that FLO11, FLO400 and FLO5-1 are involved in the phenotype, all being controlled by the transcriptional regulator Flo8. The three genes exhibit a complex mechanism of expression and repression during transition from yeast to pseudohyphal form. Unlike in S. cerevisiae, deletion of FLO11 does not completely prevent the phenotype. In contrast, deletion of FLO400 or FLO5-1 prevents pseudohyphae formation, and hampers FLO11 expression. FAIRE-Seq data shows that the expression and repression of FLO400 and FLO5-1 are correlated to open or closed chromatin regions upstream of these genes, respectively. Our findings indicate that K. phaffii Flo400 and/or Flo5-1 act as upstream signals that lead to the induction of FLO11 upon glucose limitation in chemostats at slow growth and chromatin modulation is involved in the regulation of their expression.

Regulation of dimorphism in Saccharomyces cerevisiae: involvement of the novel protein kinase homolog Elm1p and protein phosphatase 2A

1993 ◽  
Vol 13 (9) ◽  
pp. 5567-5581
Author(s):  
M J Blacketer ◽  
C M Koehler ◽  
S G Coats ◽  
A M Myers ◽  
P Madaule
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Protein Kinase ◽  
Protein Phosphatase ◽  
Nitrogen Starvation ◽  
Gene Dosage ◽  
Protein Phosphatase 2A ◽  
Pseudohyphal Growth ◽  
Phosphatase 2A ◽  
Pseudohyphal Differentiation ◽  
Novel Protein

The Saccharomyces cerevisiae genes ELM1, ELM2, and ELM3 were identified on the basis of the phenotype of constitutive cell elongation. Mutations in any of these genes cause a dimorphic transition to a pseudohyphal growth state characterized by formation of expanded, branched chains of elongated cells. Furthermore, elm1, elm2, and elm3 mutations cause cells to grow invasively under the surface of agar medium. S. cerevisiae is known to be a dimorphic organism that grows either as a unicellular yeast or as filamentous cells termed pseudohyphae; although the yeast-like form usually prevails, pseudohyphal growth may occur during conditions of nitrogen starvation. The morphologic and physiological properties caused by elm1, elm2, and elm3 mutations closely mimic pseudohyphal growth occurring in conditions of nitrogen starvation. Therefore, we propose that absence of ELM1, ELM2, or ELM3 function causes constitutive execution of the pseudohyphal differentiation pathway that occurs normally in conditions of nitrogen starvation. Supporting this hypothesis, heterozygosity at the ELM2 or ELM3 locus significantly stimulated the ability to form pseudohyphae in response to nitrogen starvation. ELM1 was isolated and shown to code for a novel protein kinase homolog. Gene dosage experiments also showed that pseudohyphal differentiation in response to nitrogen starvation is dependent on the product of CDC55, a putative B regulatory subunit of protein phosphatase 2A, and a synthetic phenotype was observed in elm1 cdc55 double mutants. Thus, protein phosphorylation is likely to regulate differentiation into the pseudohyphal state.

scholarly journals Regulation of dimorphism in Saccharomyces cerevisiae: involvement of the novel protein kinase homolog Elm1p and protein phosphatase 2A.

1993 ◽  
Vol 13 (9) ◽  
pp. 5567-5581 ◽  
Author(s):  
M J Blacketer ◽  
C M Koehler ◽  
S G Coats ◽  
A M Myers ◽  
P Madaule
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Protein Kinase ◽  
Protein Phosphatase ◽  
Nitrogen Starvation ◽  
Gene Dosage ◽  
Protein Phosphatase 2A ◽  
Pseudohyphal Growth ◽  
Phosphatase 2A ◽  
Pseudohyphal Differentiation ◽  
Novel Protein

The Saccharomyces cerevisiae genes ELM1, ELM2, and ELM3 were identified on the basis of the phenotype of constitutive cell elongation. Mutations in any of these genes cause a dimorphic transition to a pseudohyphal growth state characterized by formation of expanded, branched chains of elongated cells. Furthermore, elm1, elm2, and elm3 mutations cause cells to grow invasively under the surface of agar medium. S. cerevisiae is known to be a dimorphic organism that grows either as a unicellular yeast or as filamentous cells termed pseudohyphae; although the yeast-like form usually prevails, pseudohyphal growth may occur during conditions of nitrogen starvation. The morphologic and physiological properties caused by elm1, elm2, and elm3 mutations closely mimic pseudohyphal growth occurring in conditions of nitrogen starvation. Therefore, we propose that absence of ELM1, ELM2, or ELM3 function causes constitutive execution of the pseudohyphal differentiation pathway that occurs normally in conditions of nitrogen starvation. Supporting this hypothesis, heterozygosity at the ELM2 or ELM3 locus significantly stimulated the ability to form pseudohyphae in response to nitrogen starvation. ELM1 was isolated and shown to code for a novel protein kinase homolog. Gene dosage experiments also showed that pseudohyphal differentiation in response to nitrogen starvation is dependent on the product of CDC55, a putative B regulatory subunit of protein phosphatase 2A, and a synthetic phenotype was observed in elm1 cdc55 double mutants. Thus, protein phosphorylation is likely to regulate differentiation into the pseudohyphal state.

scholarly journals A Role for the Swe1 Checkpoint Kinase During Filamentous Growth of Saccharomyces cerevisiae

Genetics ◽  
2001 ◽  
Vol 158 (2) ◽  
pp. 549-562
Author(s):  
Roberto La Valle ◽  
Curt Wittenberg
Keyword(s):  
Solid Medium ◽  
Nitrogen Starvation ◽  
Filamentous Growth ◽  
Related Phenomenon ◽  
Morphological Response ◽  
Pseudohyphal Growth ◽  
Standard Assay ◽  
Diploid Cells ◽  
Pseudohyphal Differentiation ◽  
Assay Conditions

Abstract In this study we show that inactivation of Hsl1 or Hsl7, negative regulators of the Swe1 kinase, enhances the invasive behavior of haploid and diploid cells. The enhancement of filamentous growth caused by inactivation of both genes is mediated via the Swe1 protein kinase. Whereas Swe1 contributes noticeably to the effectiveness of haploid invasive growth under all conditions tested, its contribution to pseudohyphal growth is limited to the morphological response under standard assay conditions. However, Swe1 is essential for pseudohyphal differentiation under a number of nonstandard assay conditions including altered temperature and increased nitrogen. Swe1 is also required for pseudohyphal growth in the absence of Tec1 and for the induction of filamentation by butanol, a related phenomenon. Although inactivation of Hsl1 is sufficient to suppress the defect in filamentous growth caused by inactivation of Tec1 or Flo8, it is insufficient to promote filamentous growth in the absence of both factors. Moreover, inactivation of Hsl1 will not bypass the requirement for nitrogen starvation or growth on solid medium for pseudohyphal differentiation. We conclude that the Swe1 kinase modulates filamentous development under a broad spectrum of conditions and that its role is partially redundant with the Tec1 and Flo8 transcription factors.

Transcriptional analysis of human cytomegalovirus and rat cytomegalovirus homologues of the M73/M73.5 spliced gene family

2008 ◽  
Vol 154 (1) ◽  
pp. 65-75 ◽  
Author(s):  
Anthony A. Scalzo ◽  
Catherine A. Forbes ◽  
Lee M. Smith ◽  
Lambert C. Loh
Keyword(s):  
Gene Family ◽  
Human Cytomegalovirus ◽  
Transcriptional Analysis

scholarly journals The TOR Signal Transduction Cascade Controls Cellular Differentiation in Response to Nutrients

2001 ◽  
Vol 12 (12) ◽  
pp. 4103-4113 ◽  
Author(s):  
N. Shane Cutler ◽  
Xuewen Pan ◽  
Joseph Heitman ◽  
Maria E. Cardenas
Keyword(s):  
Signal Transduction ◽  
Protein Kinases ◽  
Protein Phosphatase ◽  
Nutrient Sensing ◽  
Yeast Cells ◽  
Regulatory Subunit ◽  
Growth Defect ◽  
Tor Pathway ◽  
Pseudohyphal Growth ◽  
Pseudohyphal Differentiation

Rapamycin binds and inhibits the Tor protein kinases, which function in a nutrient-sensing signal transduction pathway that has been conserved from the yeast Saccharomyces cerevisiaeto humans. In yeast cells, the Tor pathway has been implicated in regulating cellular responses to nutrients, including proliferation, translation, transcription, autophagy, and ribosome biogenesis. We report here that rapamycin inhibits pseudohyphal filamentous differentiation of S. cerevisiae in response to nitrogen limitation. Overexpression of Tap42, a protein phosphatase regulatory subunit, restored pseudohyphal growth in cells exposed to rapamycin. The tap42-11 mutation compromised pseudohyphal differentiation and rendered it resistant to rapamycin. Cells lacking the Tap42-regulated protein phosphatase Sit4 exhibited a pseudohyphal growth defect and were markedly hypersensitive to rapamycin. Mutations in other Tap42-regulated phosphatases had no effect on pseudohyphal differentiation. Our findings support a model in which pseudohyphal differentiation is controlled by a nutrient-sensing pathway involving the Tor protein kinases and the Tap42–Sit4 protein phosphatase. Activation of the MAP kinase or cAMP pathways, or mutation of the Sok2 repressor, restored filamentation in rapamycin treated cells, supporting models in which the Tor pathway acts in parallel with these known pathways. Filamentous differentiation of diverse fungi was also blocked by rapamycin, demonstrating that the Tor signaling cascade plays a conserved role in regulating filamentous differentiation in response to nutrients.

scholarly journals Metabolic excretion associated with nutrient-growth dysregulation promotes the rapid evolution of an overt metabolic defect

2018 ◽  
Author(s):  
Robin Green ◽  
Sonal ◽  
Lin Wang ◽  
Samuel F.M. Hart ◽  
Wenyun Lu ◽  
...  
Keyword(s):  
Cell Death ◽  
Cell Growth ◽  
Slow Growth ◽  
Rapid Evolution ◽  
Auxotrophic Mutant ◽  
Ecological Interactions ◽  
Glucose Limitation ◽  
Metabolic Defects ◽  
Fitness Advantage ◽  
Selection Of

AbstractIn eukaryotes, conserved mechanisms ensure that cell growth is coordinated with nutrient availability. Overactive growth during nutrient limitation (“nutrient-growth dysregulation”) can lead to rapid cell death. Here, we demonstrate that cells can adapt to nutrient-growth dysregulation by evolving major metabolic defects. Specifically, when yeast lysine auxotrophic mutant lys- encountered lysine limitation, an evolutionarily novel stress, cells suffered nutrient-growth dysregulation. A sub-population repeatedly evolved to lose the ability to synthesize organosulfurs (lys-orgS-). Organosulfurs, mainly glutathione and glutathione conjugates, were released by lys- cells during lysine limitation when growth was dysregulated, but not during glucose limitation when growth was regulated. Limiting organosulfurs conferred a frequency-dependent fitness advantage to lys-orgS- by eliciting a proper slow growth program including autophagy. Thus, nutrient-growth dysregulation is associated with rapid organosulfur release, which enables the selection of organosulfur auxotrophy to better tune cell growth to the metabolic environment. We speculate that evolutionarily novel stresses can trigger atypical release of certain metabolites, setting the stage for the evolution of new ecological interactions.

scholarly journals Laccase Gene Family in Cerrena sp. HYB07: Sequences, Heterologous Expression and Transcriptional Analysis

Molecules ◽  
2016 ◽  
Vol 21 (8) ◽  
pp. 1017 ◽  
Author(s):  
Jie Yang ◽  
Xinqi Xu ◽  
Tzi Ng ◽  
Juan Lin ◽  
Xiuyun Ye
Keyword(s):  
Heterologous Expression ◽  
Gene Family ◽  
Transcriptional Analysis ◽  
Laccase Gene

scholarly journals The Saccharomyces cerevisiae mutation elm4-1 facilitates pseudohyphal differentiation and interacts with a deficiency in phosphoribosylpyrophosphate synthase activity to cause constitutive pseudohyphal growth.

1994 ◽  
Vol 14 (7) ◽  
pp. 4671-4681 ◽  
Author(s):  
M J Blacketer ◽  
P Madaule ◽  
A M Myers
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Elongation ◽  
Cell Shape ◽  
Nitrogen Limitation ◽  
Single Gene ◽  
Dominant Factor ◽  
Rich Medium ◽  
Pseudohyphal Growth ◽  
Gene Coding ◽  
Pseudohyphal Differentiation

Saccharomyces cerevisiae mutant E124 was selected in a visual screen based on elongated cell shape. Genetic analysis showed that E124 contains two separate mutations, pps1-1 and elm4-1, each causing a distinct phenotype inherited as a single-gene trait. In rich medium, pps1-1 by itself causes increased doubling time but does not affect cell shape, whereas elm4-1 results in a moderate cell elongation phenotype but does not affect growth rate. Reconstructed elm4-1 pps1-1 double mutants display a synthetic phenotype in rich medium including extreme cell elongation and delayed cell separation, both characteristics of pseudohyphal differentiation. The elm4-1 mutation was shown to act as a dominant factor that potentiates pseudohyphal differentiation in response to general nitrogen starvation in a genetic background in which pseudohyphal growth normally does not occur. Thus, elm4-1 allows recognition of, or response to, a pseudohyphal differentiation signal that results from nitrogen limitation. PPS1 was isolated and shown to be a previously undescribed gene coding for a protein similar in amino acid sequence to phosphoribosylpyrophosphate synthase, a rate-limiting enzyme in the biosynthesis of nucleotides, histidine, and tryptophan. Thus, the pps1-1 mutation may generate a nitrogen limitation signal, which when coupled with elm4-1 results in pseudohyphal growth even in rich medium.

scholarly journals In Silico and Transcription Analysis of Trehalose-6-Phosphate Phosphatase Gene Family of Wheat: Trehalose Synthesis Genes Contribute to Salinity, Drought Stress and Leaf Senescence

Genes ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1652
Author(s):  
Md Ashraful Islam ◽  
Md Mustafizur Rahman ◽  
Md Mizanor Rahman ◽  
Xiujuan Jin ◽  
Lili Sun ◽  
...  
Keyword(s):  
Gene Family ◽  
Stress Tolerance ◽  
Leaf Senescence ◽  
Brachypodium Distachyon ◽  
Protein Structures ◽  
Regulatory Elements ◽  
Transcriptional Analysis ◽  
Pcr Analysis ◽  
Evolutionary Status ◽  
Transcription Analysis

Trehalose-6-phosphate phosphatase (TPP) genes take part in trehalose metabolism and also in stress tolerance, which has been well documented in many species but poorly understood in wheat. The present research has identified a family of 31 TPP genes in Triticum aestivum L. through homology searches and classified them into five clades by phylogenetic tree analysis, providing evidence of an evolutionary status with Hordeum vulgare, Brachypodium distachyon and Oryza sativa. The exon-intron distribution revealed a discrete evolutionary history and projected possible gene duplication occurrences. Furthermore, different computational approaches were used to analyze the physical and chemical properties, conserved domains and motifs, subcellular and chromosomal localization, and three-dimensional (3-D) protein structures. Cis-regulatory elements (CREs) analysis predicted that TaTPP promoters consist of CREs related to plant growth and development, hormones, and stress. Transcriptional analysis revealed that the transcription levels of TaTPPs were variable in different developmental stages and organs. In addition, qRT-PCR analysis showed that different TaTPPs were induced under salt and drought stresses and during leaf senescence. Therefore, the findings of the present study give fundamental genomic information and possible biological functions of the TaTPP gene family in wheat and will provide the path for a better understanding of TaTPPs involvement in wheat developmental processes, stress tolerance, and leaf senescence.

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