Max Planck Institutes and Experts

Autophagy is a recycling system of the cell that prevents all kinds of cellular waste from accumulating. Autophagy sequesters such material in specialized containers, which are like other organelles of the cell surrounded by a flexible membrane. These containers transport their contents to cellular recycling stations for degradation. The researchers recently identified a specialized set of proteins that stabilize autophagic containers. Similar to recycling bins, these proteins form a stiff shell on top of the membrane to provide physical support.

In spite of the great progress of the biosciences during the last decades, the very line of division between the animate and inanimate world still remains elusive. One of the most distinctive features of living systems is their compositional and organizational complexity, but how complex does life really have to be? Our research aims to identify a minimal set of fundamental features and governing principles of biological cells - being the smallest units of life - to enable their comprehensive biophysical, i.e., quantitative characterization by a defined set of parameters.

How complex but stereotyped tissues are formed, maintained and regenerated through local growth, differentiation and remodeling is a fundamental open question in biology. To answer this question we need to understand how single cell behaviors are coordinated on the population level and how population-level dynamics are coupled to tissue architecture. Uncovering these regulatory principles will further facilitate development of stem cell therapies and effective treatments to slow down ageing and prevent age-related diseases such as cancer.

Proteins are the workhorses of our cells. To fulfill their roles they need to adopt a functional conformation. Scientists have now experimentally determined how fast proteins are made and have shown that the correct speed is critical for functional folding. Perturbing translation leads to protein aggregates. This can cause severe developmental defects in mice. Their brain cells receive the wrong differentiation signal due to protein stress. These results answer a fundamental question of molecular biology and have far reaching consequences for neurodegenerative diseases and biotechnology.

The basic features of the body organisation of adult plants are established during embryogenesis. This process starts from the fertilized egg cell (zygote), which divides into an apical embryonic cell and a basal extra-embryonic cell. How this initial difference originates with input from the YODA pathway is briefly discussed. These cells give rise to embryo and extra-embryonic suspensor, respectively. The embryonic cells then generate, in response to the plant hormone auxin, a signal that stimulates the adjacent extra-embryonic cell to initiate the formation of the embryonic root meristem.