Research in the lab focuses on two important areas at the interface between molecular cell biology and medicine:
- Molecular mechanisms in the organization of specialised domains in the sarcoplasmic reticulum of muscle cells
One of the major traits that distinguish eukaryotic from prokaryotic cells is their ability to segregate cellular functions to specific internal compartments, which are basically represented by intracellular organelles. Each of the many types of organelles (lysosomes, mithochondria, endoplasmic reticulum etc.) is devoted to a particular function or set of functions and is, therefore, functionally and structurally distinct from the others. Among intracellular organelles, the endoplasmic reticulum certainly represents the largest membrane system in eukaryotic cells and is primarily involved in lipid and protein synthesis and in Ca2+ storage. These functions are segregated to specific endoplasmic reticulum domains that are basically represented by the smooth and the rough endoplasmic reticulum, although a number of membrane sub-domains are present. An example of this complex sub-compartimentalization is observed in muscle cells where the smooth endoplasmic reticulum is mostly represented by the sarcoplasmic reticulum, a network of tubules and cisternae mainly devoted to Ca2+ storage. We are interested in molecular identification of the mechanisms directing the organization of sarcoplasmic reticulum domains and the targeting of sarcoplasmic reticulum proteins to specific sub-compartments.
- Mechanisms that regulate proliferative and differentiative potentials of human adult stem cells
Generation of tissues and organs during development is carried out by stem cells, which are special cells capable to self-renew as well as to give rise to differentiated cells. Embryonic stem cells, which are capable to generate all three tissue layers, are considered multipotent as they can contribute to the entire organism when injected into blastocysts. Stem cells with more restricted potential are present during adult life. These adult stem cells are responsible for the repair and regeneration of specific organs such as the skin, blood, and other organs. Isolation of adult stem cells is difficult because of the poor definition of the phenotype of these cells. Similarly, conditions for expansion of adult stem cells in vitro are also poorly defined. An improvement of our knowledge on the identification and expansion of adult stem cells is of fundamental interest to discover the basic molecular and cellular mechanisms that regulate proliferation and differentiation in these cells. This information is also extremely important if we want to develop new strategies for therapeutic use of these cells in human diseases.
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