How cells decide on their fate?

Our goal is to understand how cells within a population reach developmental decisions at the phenotypic and mechanistic level. How do cells “decide” to change their state? Why do similar cells respond differently to the same signal? What properties of the cell affect its decision? What determines these properties and their spread in the cell population? What determines which cell states are stable? Our lab studies these fundamental questions in two model systems using methods from live cell fluorescent imaging, microfluidics, statistical and computational analysis.

We are looking for highly motivated postdocs, PhD and MSc students. Please contact Iftach for details.

Control of timing in transcription regulatory networks

During cell state changes, master regulators need to orchestrate the timely activation of many different proteins. How does a master transcriptional regulator control its targets differentially? Can it achieve consistent timing differences in their activation? Does the variability in its levels generate variable onset times or variable levels of its targets? We study the accuracy, reproducibility and temporal structure of a transcriptional response at the single cell level, using the early meiosis transcriptional module as a model system.

Information processing by signalling networks

Cell populations in the nature face different cues from the environment that change at different frequencies. For example, a yeast colony in the vineyard senses different levels of heat, humidity, osmolarity and nutrient levels changing at different rates. Effective response to these fluctuating cues raises several challenges. Can the cells distinguish between a fleeting cue and a consistent change? Can they filter out the former to avoid mistaken decisions? How do their signaling and transcriptional networks handle these complex fluctuations? We study the decision responses to signal fluctuations in the yeast meiosis process using live cell microscopy and custom-designed microfluidic devices capable of generating spatial and temporal signal gradients.

Early decisions in mammalian cell reprogramming

In this process, whose development is a major breakthrough of recent years, a population of identical adult cells is directed to pluripotency by forced activation of four transcription factors, yet only a small fraction ends up in the desired state. We want to understand the dynamics of the process, its different phases, and the different paths cells can take during reprogramming. We perform live imaging of the entire reprogramming process, combining live fluorescent markers and immuno-staining at intermediate points. We have delineated the stages of the process, and will try to back-track the determinants of successful reprogramming and study the alternative fates adopted by other cells in the process.

Contact

Nachman lab
Department of Biochemistry and Molecular Biology
George S. Wise Faculty of Life Sciences
Sherman building, room 506
Tel Aviv University
Tel Aviv 69978
Israel

Tel: +972-3-640-5900
Fax: +972-3-640-9442
iftachn@post.tau.ac.il