לוח שנה משולב

It has long been expected theoretically that quantum fluctuations may destroy anti ferromagnetic order in certain "frustrated" systems, but it is only in the past few years that experimental systems showing this behavior have been discovered. Indeed these systems show signs of predicted "emergent' new par-ticles such as neutral spin 1/2 fermionic excitations called spinons. I shall review the recent develop-ment and discuss possible connection to superconductivity.

Cell behaviour (e.g. migration, adhesion, polarization) is regulated in many essential ways by the activity of the cytoskeletal actin microfilament. The actin filament undergoes continuous dynamic rearrangements of G-actin polymerization and F-actin depoly¬merization. Changes in cell behaviour which are governed by actin dynamics are tightly linked to changes in gene expression. The state of actin polymerization is communicated to the nucleus by proteins of the myocardin-related transcription factor (MRTF) family which are released from cytoplasmic G-actin anchorage upon stimulation of F-actin extension. Upon translocation to the nucleus, MRTF proteins activate the transcription factor SRF (serum response factor) to stimulate the transcription of a large set of cytoskeletal SRF target genes, including the actin gene itself. The seminar will discuss roles of MRTF-SRF gene control during muscle function, neuronal migration, and liver tumor formation. The results to be discussed were generated by both SRF loss-of-function and gain-of-function genetic studies using the mouse model.