Seminar CeNT 20.12.2019

17 grudnia 2019

The Centre of New Technologies invites to a seminar by

Prof. Michael Feig

Michigan State University, USA

Title: Cellular crowding near membranes: Implications for biomolecular diffusion and clustering

Date: 20 December (Friday) 2019 at 12 p.m.

Venue: Centre of New Technologies, Banacha 2C,
Lecture Hall 0142 (ground floor)

Host: Prof. Joanna Trylska

 Abstract

The interior of biological cells is highly crowded with very high macromolecular concentrations that impact biomolecular stability, diffusion, and solubility. While there is some understanding of these effects inside the cytoplasm, very little is known how the presence of membrane surfaces modulates crowding effects. Biological membranes represent the outer boundary of cells, but they are also present inside cells to contain organelles and in the endoplasmic reticulum or Golgi apparatus. To gain insights into how a crowded environment may interact with membrane surfaces, results from computer simulations of concentrated protein solutions near phospholipid bilayers over microsecond time scales are presented¹. The main insight is that the presence of the membrane appears to create a protein depletion zone at the membrane surface that leads to increased clustering and slower diffusion away from the membrane but allows proteins that enter this zone to overcome the slow diffusion that is otherwise encountered in the crowded bulk environment. In addition, proteins that do interact with the membrane surface appear to induce curvature. The finding is similar to crowding-induced membrane bending reported previously but without requiring specific membrane-interacting protein domains. The results are further interpreted via coarse-grained models to access larger spatial and temporal scales and results with pure lipid bilayers are compared with simulations where an integral membrane protein was embedded into the bilayer.

¹G. Nawrocki, W. Im, Y. Sugita, M. Feig: Clustering and Dynamics of Crowded Proteins near Membranes and Their Influence on Membrane Bending. PNAS (2019), 116, 24562-24567

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Christmas with the Psychological Counselling Centre

Psychologists from the UW Psychological Counselling Centre (CPP) will be available for UW students and employees also around Christmas time. Watch a video with Dr. Szymon Chrząstowski encouraging those who do not feel comfortable in this period or face some difficult situations, to come for short conversations.

Christmas is a time of joy and happiness. However, some people feel stressed while thinking of Christmas.

“For many people Christmas is a great opportunity to relax, meet loved ones and finally have some joy. Some people, however, are very nervous about the holidays, they are nervous about meeting their loved ones, they fear how these holidays will go,” says Dr. Szymon Chrząstowski, head of CPP.

 

 

Being on an international exchange programme may be a great experience, but it is also a challenge. The new environment, new relationships, and language barriers can be overwhelming and not easy to handle. If you experience an unpleasant situation or simply feel stressed because you can not spend this time with your family, contact CPP to receive professional help.

Those who stay in Warsaw over a Christmas holiday break and would like to talk to a psychologist can visit the centre.

It is also possible to arrange an online appointment via Skype.

 

Source: www.en.uw.edu.pl

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