Budding Yeast Cells Research Articles

Direct measurements of colloidal behavior of polystyrene nanoparticles into budding yeast cells using atomic force microscopy and confocal microscopy

The colloidal behavior of positively charged polystyrene latex (PSL) nanoparticles (NPs) toward yeast cells (Saccharomyces cerevisiae) was investigated using atomic force microscopy (AFM) and confocal laser scanning microscopy (CLSM). AFM imaging revealed that the conically-shaped pits connected with endocytosis were observed in 154 mM NaCl, and the surface was completely covered with NPs within 60 s in 5 mM NaCl. AFM force measurements revealed that the adhesion rate of NPs in 5 mM NaCl was faster than that in 154 mM NaCl. This strongly suggested that in 5 mM NaCl, the NPs accumulated on the cell surface over a short time followed by cell death. Furthermore, the accumulation of NPs on the cell surface in 5 mM NaCl could be suppressed by adding polyethylene glycol to the medium, resulting in an increase in the number of living cells. This suggests that the adhesion rate of NPs primarily depended on the interaction forces between the surfaces, and the viscosity of the medium. Thus, the colloidal behavior of the positively charged PSL NPs toward yeast cells was controlled by the balance between the adhesion rate of NPs on the cells and the uptake rate of NPs into the cells. Additionally, the uptake of the PSL NPs and an endocytosis marker into the cells was inhibited by Latrunculin B and NaN3. However, their locations without inhibitor treatment were obviously different, indicating that NPs were not transported to the vacuole and accumulated in the vesicles.

Fine tuning the level of the Cdc13 telomere-capping protein for maximal chromosome stability performance.

Chromosome stability relies on an adequate length and complete replication of telomeres, the physical ends of chromosomes. Telomeres are composed of short direct repeat DNA and the associated nucleoprotein complex is essential for providing end-stability. In addition, the so-called end-replication problem of the conventional replication requires that telomeres be elongated by a special mechanism which, in virtually all organisms, is based by a reverse transcriptase, called telomerase. Although, at the conceptual level, telomere functions are highly similar in most organisms, the telomeric nucleoprotein composition appears to diverge significantly, in particular if it is compared between mammalian and budding yeast cells. However, over the last years, the CST complex has emerged as a central hub for telomere replication in most systems. Composed of three proteins, it is related to the highly conserved replication protein A complex, and in all systems studied, it coordinates telomerase-based telomere elongation with lagging-strand DNA synthesis. In budding yeast, the Cdc13 protein of this complex also is essential for telomerase recruitment and this specialisation is accompanied by additional regulatory adaptations. Based on recent results obtained in yeast, here, we review these issues and present an updated telomere replication hypothesis. We speculate that the similarities between systems far outweigh the differences, once we detach ourselves from the historic descriptions of the mechanisms in the various organisms.

Deregulation of the G1/S-phase transition is the proximal cause of mortality in old yeast mother cells.

Budding yeast cells produce a finite number of daughter cells before they die. Why old yeast cells stop dividing and die is unclear. We found that age-induced accumulation of the G1/S-phase inhibitor Whi5 and defects in G1/S cyclin transcription cause cell cycle delays and genomic instability that result in cell death. We further identified extrachromosomal rDNA (ribosomal DNA) circles (ERCs) to cause the G1/S cyclin expression defect in old cells. Spontaneous segregation of Whi5 and ERCs into daughter cells rejuvenates old mothers, but daughters that inherit these aging factors die rapidly. Our results identify deregulation of the G1/S-phase transition as the proximal cause of age-induced proliferation decline and cell death in budding yeast.

Cerebral Candida albicans Infection in Two dogs

Background: Candida spp. are pleomorphic fungi that are commensal inhabitants of the oral, gastrointestinal, upper respiratory and urogenital mucosa of mammals. Candida albicans is described as the most important species. This opportunistic pathogen may produce local or systemic infections in dogs. Local infections have been reported in several tissues and systemic infection is rare in dogs with few reports in the literature describing this presentation. The aim of the present study was to report two cases of cerebral Candida albicans infection in dogs in Brazil.Case: Two cases of cerebral Candida albicans infection in dogs that showed nervous signs are described. In both cases, the brain showed marked asymmetry of the telencephalic hemispheres with multifocal to coalescing yellowish or reddish areas and a partial loss of distinction between gray and white matter. In Case 1, the mediastinal, tracheobronchial and mesenteric lymph nodes, as well as the right kidney and adrenal gland, showed altered architecture due to numerous whitish gray nodules. Histological lesions were characterized by granulomatous (case 1) or pyogranulomatous (case 2) necrotizing meningoencephalitis with intralesional fungal organisms. In case 1, similar granulomatous infiltrate with intralesional fungal organisms was also seen in the lymph nodes, kidney and adrenal gland. In case 2, there was evidence consistent with an underlying infection of canine distemper virus. Were observed lymphoplasmocytic interstitial pneumonia, lymphoid rarefaction in lymph nodes, and viral intracytoplasmic inclusion bodies in the epithelial cells of the stomach and vesical urothelium. In these two cases, the fungal organisms displayed three different morphological patterns. The first pattern was characterized by delicate tubular structures with thin parallel walls that were rarely septate and tended to undulate slightly, and measured approximately 4-20 µm (true hyphae). The second pattern was characterized by chains of elongated yeast, separated by constrictions at septal sites, and measured approximately 4-10 µm (pseudohyphae). The other morphological pattern, which was rarely observed, was characterized by round budding yeast cells that measured 3-4 µm in diameter and were often elongated by the germ tube. Sections were also stained using immunohistochemical antibodies against Candida albicans. The fungi revealed strong immunolabelling of the cytoplasm and wall for Candida albicans.Discussion: The diagnosis was based on the histomorphological and immunohistochemical characteristics of the agent, which were consistent with Candida albicans. In these two cases, immunocompromise appeared to have been an important factor in the progression of the infection. In case 1, the dog was senile and treated with corticosteroids, conditions that could effectively limit innate, humoral and cell-mediated immune response to infection. In case 2, the dog displayed cachexia and was infected by canine distemper virus, evidenced by the presence of viral inclusion bodies. The inflammatory reactions in both cases were characteristic of fungal infections, but were distinct due to differences in the infectious process. In case 1, there was a subacute to chronic progression; while in case 2 neutrophilic infiltrate predominated, suggesting an acute progression. The different morphological patterns of the fungi suggested a pleomorphic fungi and the immunohistochemistry allowed us to identify the infectious agent. In conclusion, opportunistic infections caused by Candida albicans should be considered when diagnosing diseases that affect the central nervous system of dogs, particularly in immunosuppressed animals.

Protein Synthesis Initiation in Eukaryotic Cells.

This review summarizes our current understanding of the major pathway for the initiation phase of protein synthesis in eukaryotic cells, with a focus on recent advances. We describe the major scanning or messenger RNA (mRNA) m7G cap-dependent mechanism, which is a highly coordinated and stepwise regulated process that requires the combined action of at least 12 distinct translation factors with initiator transfer RNA (tRNA), ribosomes, and mRNAs. We limit our review to studies involving either mammalian or budding yeast cells and factors, as these represent the two best-studied experimental systems, and only include a reference to other organisms where particular insight has been gained. We close with a brief description of what we feel are some of the major unknowns in eukaryotic initiation.

Family or career? I want both-the control of meiosis.

In this paper I describe my professional and personal journey in science. In the 20th century there were fewer women scientists than man scientists. My personal experience and opinion is that women avoided academic careers. How one can combine family and career is discussed. The interest in science and the interactions I had with prominent leading Yeast Scientists changed my point of view, I matured and developed an academic career. My research focused on how budding yeast cells chose to exit the cell cycle and enter meiosis. My journey started using classical Genetic techniques. The development of Genetic engineering techniques enabled us to verify models and elucidate how entry into meiosis is controlled.

Snf1/AMPK is involved in the mitotic spindle alignment in Saccharomyces cerevisiae

Before anaphase onset, budding yeast cells must align the mitotic spindle parallel to the mother-bud axis to ensure proper chromosome segregation. The protein kinase Snf1/AMPK is a highly conserved energy sensor, essential for adaptation to glucose limitation and in response to cellular stresses. However, recent findings indicate that it plays important functions also in non-limiting glucose conditions. Here we report a novel role of Snf1/AMPK in the progression through mitosis in glucose-repressing condition. We show that active Snf1 is localized to the bud neck from bud emergence to cytokinesis in a septin-dependent manner. In addition, loss of Snf1 induces a delay of the metaphase to anaphase transition that is due to a defect in the correct alignment of the mitotic spindle. In particular, genetic data indicate that Snf1 promotes spindle orientation acting in parallel with Dyn1 and in concert with Kar9. Altogether this study describes a new role for Snf1 in mitosis and connects cellular metabolism to mitosis progression.

Stoichiometry and compositional plasticity of the yeast nuclear pore complex revealed by quantitative fluorescence microscopy

The nuclear pore complex (NPC) is an eightfold symmetrical channel providing selective transport of biomolecules across the nuclear envelope. Each NPC consists of ∼30 different nuclear pore proteins (Nups) all present in multiple copies per NPC. Significant progress has recently been made in the characterization of the vertebrate NPC structure. However, because of the estimated size differences between the vertebrate and yeast NPC, it has been unclear whether the NPC architecture is conserved between species. Here, we have developed a quantitative image analysis pipeline, termed nuclear rim intensity measurement (NuRIM), to precisely determine copy numbers for almost all Nups within native NPCs of budding yeast cells. Our analysis demonstrates that the majority of yeast Nups are present at most in 16 copies per NPC. This reveals a dramatic difference to the stoichiometry determined for the human NPC, suggesting that despite a high degree of individual Nup conservation, the yeast and human NPC architecture is significantly different. Furthermore, using NuRIM, we examined the effects of mutations on NPC stoichiometry. We demonstrate for two paralog pairs of key scaffold Nups, Nup170/Nup157 and Nup192/Nup188, that their altered expression leads to significant changes in the NPC stoichiometry inducing either voids in the NPC structure or substitution of one paralog by the other. Thus, our results not only provide accurate stoichiometry information for the intact yeast NPC but also reveal an intriguing compositional plasticity of the NPC architecture, which may explain how differences in NPC composition could arise in the course of evolution.

Robustness and evolvability of heterogeneous cell populations.

Biological systems are endowed with two fundamental but seemingly contradictory properties: robustness, the ability to withstand environmental fluctuations and genetic variability; and evolvability, the ability to acquire selectable and heritable phenotypic changes. Cell populations with heterogeneous genetic makeup, such as those of infectious microbial organisms or cancer, rely on their inherent robustness to maintain viability and fitness, but when encountering environmental insults, such as drug treatment, these populations are also poised for rapid adaptation through evolutionary selection. In this study, we develop a general mathematical model that allows us to explain and quantify this fundamental relationship between robustness and evolvability of heterogeneous cell populations. Our model predicts that robustness is, in fact, essential for evolvability, especially for more adverse environments, a trend we observe in aneuploid budding yeast and breast cancer cells. Robustness also compensates for the negative impact of the systems’ complexity on their evolvability. Our model also provides a mathematical means to estimate the number of independent processes underlying a system’s performance and identify the most generally adapted subpopulation, which may resemble the multi-drug-resistant “persister” cells observed in cancer.

Nanoscale domain formation of phosphatidylinositol 4-phosphate in the plasma and vacuolar membranes of living yeast cells

In budding yeast Saccharomyces cerevisiae, PtdIns(4)P serves as an essential signalling molecule in the Golgi complex, endosomal system, and plasma membrane, where it is involved in the control of multiple cellular functions via direct interactions with PtdIns(4)P-binding proteins. To analyse the distribution of PtdIns(4)P in yeast cells at a nanoscale level, we employed an electron microscopy technique that specifically labels PtdIns(4)P on the freeze-fracture replica of the yeast membrane. This method minimizes the possibility of artificial perturbation, because molecules in the membrane are physically immobilised in situ. We observed that PtdIns(4)P is localised on the cytoplasmic leaflet, but not the exoplasmic leaflet, of the plasma membrane, Golgi body, vacuole, and vesicular structure membranes. PtdIns(4)P labelling was not observed in the membrane of the endoplasmic reticulum, and in the outer and inner membranes of the nuclear envelope or mitochondria. PtdIns(4)P forms clusters of <100 nm in diameter in the plasma membrane and vacuolar membrane according to point pattern analysis of immunogold labelling. There are three kinds of compartments in the cytoplasmic leaflet of the plasma membrane. In the present study, we showed that PtdIns(4)P is specifically localised in the flat undifferentiated plasma membrane compartment. In the vacuolar membrane, PtdIns(4)P was concentrated in intramembrane particle (IMP)-deficient raft-like domains, which are tightly bound to lipid droplets, but not surrounding IMP-rich non-raft domains in geometrical IMP-distributed patterns in the stationary phase. This is the first report showing microdomain formations of PtdIns(4)P in the plasma membrane and vacuolar membrane of budding yeast cells at a nanoscale level, which will illuminate the functionality of PtdIns(4)P in each membrane.

Hsf1 Phosphorylation Generates Cell-to-Cell Variation in Hsp90 Levels and Promotes Phenotypic Plasticity

SUMMARYClonal populations of cells exhibit cell-to-cell variation in the transcription of individual genes. In addition to this noise in gene expression, heterogeneity in the proteome and the proteostasis network expands the phenotypic diversity of a population. Heat shock factor 1 (Hsf1) regulates chaperone gene expression, thereby coupling transcriptional noise to proteostasis. Here we show that cell-to-cell variation in Hsf1 activity is an important determinant of phenotypic plasticity. Budding yeast cells with high Hsf1 activity were enriched for the ability to acquire resistance to an antifungal drug, and this enrichment depended on Hsp90, a known phenotypic capacitor and canonical Hsf1 target. We show that Hsf1 phosphorylation promotes cell-to-cell variation, and this variation, rather than absolute Hsf1 activity, promotes antifungal resistance. We propose that Hsf1 phosphorylation enables differential tuning of the proteostasis network in individual cells, allowing populations to access a range of phenotypic states.

Characterization of Cell Boundary and Confocal Effects Improves Quantitative FRAP Analysis

Fluorescence recovery after photobleaching (FRAP) is an important tool used by cell biologists to study the diffusion and binding kinetics of vesicles, proteins, and other molecules in the cytoplasm, nucleus, or cell membrane. Although many FRAP models have been developed over the past decades, the influence of the complex boundaries of 3D cellular geometries on the recovery curves, in conjunction with regions of interest and optical effects (imaging, photobleaching, photoswitching, and scanning), has not been well studied. Here, we developed a 3D computational model of the FRAP process that incorporates particle diffusion, cell boundary effects, and the optical properties of the scanning confocal microscope, and validated this model using the tip-growing cells of Physcomitrella patens. We then show how these cell boundary and optical effects confound the interpretation of FRAP recovery curves, including the number of dynamic states of a given fluorophore, in a wide range of cellular geometries—both in two and three dimensions—namely nuclei, filopodia, and lamellipodia of mammalian cells, and in cell types such as the budding yeast, Saccharomyces pombe, and tip-growing plant cells. We explored the performance of existing analytical and algorithmic FRAP models in these various cellular geometries, and determined that the VCell VirtualFRAP tool provides the best accuracy to measure diffusion coefficients. Our computational model is not limited only to these cells types, but can easily be extended to other cellular geometries via the graphical Java-based application we also provide. This particle-based simulation—called the Digital Confocal Microscopy Suite or DCMS—can also perform fluorescence dynamics assays, such as number and brightness, fluorescence correlation spectroscopy, and raster image correlation spectroscopy, and could help shape the way these techniques are interpreted.

Accelerated invagination of vacuoles as a stress response in chronically heat-stressed yeasts

When exposed to sublethal high temperatures, budding yeast cells can survive for a period of time; however, a sufficient amount of ubiquitin is necessary for this survival. To understand the nature of the stress, we examined the morphological changes in yeast cells, focusing on the vacuoles. Changes in vacuolar morphology were notable, and ruffled vacuolar membranes, accelerated invaginations of vacuolar membranes, and vesicle-like formations were observed. These changes occurred in the absence of Atg1, Atg9 or Ivy1 but appeared to require endosomal sorting proteins, such as Vps23, Vps24 or Pep12. Furthermore, the serial sections of the vacuoles analysed using an electron microscopic analysis revealed that spherical invaginated structures were linked together in a vacuole. Because degradation of cell surface proteins is induced from heat stress, fusion of endosomal and vacuolar membranes might occur frequently in heat-stressed cells, and yeast cells might be able to cope with a rapid increase in vacuolar surface area by such invaginations.

Synthetic gene regulation for independent external induction of the Saccharomyces cerevisiae pseudohyphal growth phenotype

Pseudohyphal growth is a multicellular phenotype naturally performed by wild budding yeast cells in response to stress. Unicellular yeast cells undergo gross changes in their gene regulation and elongate to form branched filament structures consisting of connected cells. Here, we construct synthetic gene regulation systems to enable external induction of pseudohyphal growth in Saccharomyces cerevisiae. By controlling the expression of the natural PHD1 and FLO8 genes we are able to trigger pseudohyphal growth in both diploid and haploid yeast, even in different types of rich media. Using this system, we also investigate how members of the BUD gene family control filamentation in haploid cells. Finally, we employ a synthetic genetic timer network to control pseudohyphal growth and further explore the reversibility of differentiation. Our work demonstrates that synthetic regulation can exert control over a complex multigene phenotype and offers opportunities for rationally modifying the resulting multicellular structure.

Genomic and Phenotypic Variation in Morphogenetic Networks of Two Candida albicans Isolates Subtends Their Different Pathogenic Potential

The transition from commensalism to pathogenicity of Candida albicans reflects both the host inability to mount specific immune responses and the microorganism’s dimorphic switch efficiency. In this study, we used whole genome sequencing and microarray analysis to investigate the genomic determinants of the phenotypic changes observed in two C. albicans clinical isolates (YL1 and YQ2). In vitro experiments employing epithelial, microglial, and peripheral blood mononuclear cells were thus used to evaluate C. albicans isolates interaction with first line host defenses, measuring adhesion, susceptibility to phagocytosis, and induction of secretory responses. Moreover, a murine model of peritoneal infection was used to compare the in vivo pathogenic potential of the two isolates. Genome sequence and gene expression analysis of C. albicans YL1 and YQ2 showed significant changes in cellular pathways involved in environmental stress response, adhesion, filamentous growth, invasiveness, and dimorphic transition. This was in accordance with the observed marked phenotypic differences in biofilm production, dimorphic switch efficiency, cell adhesion, invasion, and survival to phagocyte-mediated host defenses. The mutations in key regulators of the hyphal growth pathway in the more virulent strain corresponded to an overall greater number of budding yeast cells released. Compared to YQ2, YL1 consistently showed enhanced pathogenic potential, since in vitro, it was less susceptible to ingestion by phagocytic cells and more efficient in invading epithelial cells, while in vivo YL1 was more effective than YQ2 in recruiting inflammatory cells, eliciting IL-1β response and eluding phagocytic cells. Overall, these results indicate an unexpected isolate-specific variation in pathways important for host invasion and colonization, showing how the genetic background of C. albicans may greatly affect its behavior both in vitro and in vivo. Based on this approach, we propose that the co-occurrence of changes in sequence and expression in genes and pathways driving dimorphic transition and pathogenicity reflects a selective balance between traits favoring dissemination of the pathogen and traits involved in host defense evasion. This study highlights the importance of investigating strain-level, rather than species level, differences, when determining fungal–host interactions and defining commensal or pathogen behavior.

Participation of Septin Cytoskeletal Proteins in the Nervous System Functioning

Septins, the cytoskeletal proteins discovered in the 1970s in budding yeast cells, are currently detected in most postmitotic cells of animals and humans. In the last decade, significant progress has been made in understanding the biochemical properties of septins and their biological functions. An increasing number of studies show that these proteins play an important role in the development and physiology of specific tissues and organs. The review surveys classification, major functions and localization of septins in the nervous system of mammals and humans. Models describing the mechanisms of the septin involvement in the neurotransmitter secretion from nerve endings and the role of septins in the pathogenesis of various neurodegenerative diseases are discussed.

Nutritional and environmental factors affecting the morphogenesis of Candida albicans: A key to virulence

Candida albicans is an opportunistic fungal pathogen that plays an important role in the early part of infectious process by extravagating and disseminating to the target organs, whereas hyphal forms appear to be required for the mortality resulting from a deep-seated infection. C. albicans morphogenesis is regulated by numerous environmental cues and other signaling pathways. We investigated the morphogenesis in C. albicans in the presence of serum at different temperatures (20 oC, 30 oC and 37 oC). C. albicans were also grown in simple growth medium 'SDB' and subsequently cultured from Fetal bovine serum and Soybeans dextrose broth (SDB) on Sabouraud dextrose agar, Yeast extract potato dextrose agar and Spider medium. The combination of serum and temperature is excellent at promoting the yeast to mycelial conversion and it also induces the expression of hyphal specific genes. Our results demonstrate that the combination of serum and each temperature provides a distinct proportion of blastospores, budding yeast cells, germ tube, pseudohyphae and true hyphal cells. Remarkable change in colonial pattern between the cells cultured after incubating in serum and the cells cultured after incubating in SDB was observed in SDA in contrast with YEPD and Spider medium. On most solid media, colonies of C. albicans are composed of three types of cells: budding yeast, pseudohyphae and hyphae. All three forms are also found in infected tissues, and the transition between these forms is a key for pathogenesis.

Single-probe RNA FISH in Yeast.

Quantitative profiling of mRNA expression is an important part of understanding the state of a cell. The technique of RNA Fluorescence In Situ Hybridization (FISH) involves targeting an RNA transcript with a set of 40 complementary fluorescently labeled DNA oligonucleotide probes. However, there are many circumstances such as transcripts shorter than 200 nt, splicing variations, or alternate initiation sites that create transcripts that would be indistinguishable to a set of multiple probes. To this end we adapted the standard FISH protocol to allow the use of a single probe with a single fluorophore to quantify the amount of transcripts inside budding yeast cells. In addition to allowing the quantification of short transcripts or short features of transcripts, this technique reduces the cost of performing FISH.

Cryptococcal meningitis presented with irreversible binocular blindness in an HIV infected patient- A case report

Cryptococcal meningitis is a major HIV-related opportunistic infection, occurring when CD4 counts are below 100. Ocular involvement is seen with up to 30% of patients with cryptococcal meningitis. A young HIV infected male was admitted to in patient department of School of Tropical Medicine, Calcutta with complaints of headache for two months with dimness of vision for 10 days. Examination showed decreased visual acuity on both eyes, neck rigidity with right sided extensor plantar reflex, external ophthalmoplegia in the form of left 6th cranial nerve palsy, bilaterally absent light reflex, power 5/5 in all four limbs with normal tone and right eye hypermetropic tilted disc, left eye normal on ophthalmoscopy. India Ink preparation of CSF showed encapsulated budding yeast cells. Fungal culture grows Cryptococcus sp. CSF CRAG (cryptococcal antigen measured by immunochromatographic method) was positive in high titre (1:2560). MRI of brain revealed multiple tiny hypo to isointense lesions on T1 and hyperintense lesions on T2, T2 flair sequences are seen in basal ganglia, peri & paraventricular white matter and centrum semi-ovale on both sides. He was managed with injection amphotericin B deoxycholate along with fluconazole as per WHO recommendations and treatment related complications were managed accordingly. Visual acuity was followed in the entire treatment period but vision did not improve, but GCS improved to 15/15, there was no headache, no neck rigidity. Repeat MRI of brain after three weeks of treatment showed absence of above mentioned lesions. After 12 months of follow up the patient had no perception of light in both eyes and no wave in VEP study of both eyes suggestive of permanent visual loss following cryptococcal meningitis. So, cryptococcal meningitis after completion of treatment may have irreversible visual loss.

Monitoring of the Budding Yeast Cell Cycle Using Electrical Parameters

Finding non-invasive and label-free techniques that allow real-time monitoring of living cells is a field of intensive research with first trials dating back to a century. Employing dielectric spectroscopy on biological materials has aided in deciphering many aspects of living cells, such as cell structure and physiology. In this paper, we studied the dielectric parameters of budding yeast cell suspension as they progressed through the cell cycle. This was done by measuring the capacitance–voltage profile as well as other electrical parameters of cells at different phases of the cell cycle. For this purpose, cells were initially synchronized at the G1 phase and then released in the culture media. Samples at different time points were taken, and both electrical and flow cytometry analyses were carried out. In this paper, we have measured the electrical parameters of the yeast cells as they progress through the cell cycle at very low frequencies, which is believed to preserve all the mechanisms of polarization in yeast cell suspensions. In addition, this allows us to observe electrical changes independent of initial cell numbers. The results reveal an incremental increase in the capacitance–voltage profile as cells progressed through the cell cycle. The capacitance–voltage profile could be used to determine the doubling time of the yeast cells. Studying the yeast doubling time is important in the real-time assessment of different strains/mutants in terms of their progress through the cell cycle and any potential differences between yeast strains. Electrical-based techniques are more sensitive to small changes that occur in cells, which cannot be traced by other methods such as fluorescence-activated cell sorting (FACS). Moreover, if such a technique, used in this paper, is integrated into a multiplexing system, which allows parallel and simultaneous runs, it could potentially be more powerful than FACS for offering real-time automated measurements of cell cycle progress, avoiding the lengthy processing time required by FACS.