What do they focus on at the Department of the Histology and Embryology? What direction does their research take? Marek Bárta M.Sc., PhD gave us these answers himself.
Could you briefly explain what the organoids are?
Our research group has recently focused on retinal organoids generated from human pluripotent stem cells. Organoids are small, three-dimensional structures that largely recapitulate the structure and function of an organ. They represent, therefore, a suitable experimental system for studying the development of organs and tissues, their physiology, for testing new drugs and modelling diseases. Many tissue or organ-specific organoids have been generated including the brain, intestine, kidneys, liver, lungs, pancreas, prostate, mammary gland, and retinal organoids.
What are the mentioned retina and researched retinal organoids?
The retina is composed of a thin layer of tissue that is sensitive to light. Photoreceptors, retinal ganglion cells, bipolar cells, amacrine cells, and horizontal cells are interconnected to form one of the most complex cellular networks that, when exposed to light, can generate an electrical signal that is transmitted through other retinal neurons to the optic nerve and then to the brain. The structure and cellular composition of retinal organoids resemble human retina to some extent. Retinal organoids during their differentiation recapitulate the development of the human retina and thus they are widely used in developmental biology to study the individual molecular signalling pathways and genes that regulate the development of the eye (Figure 1).
What have you investigated in your study?
In our study, recently published in the journal Stem Cells, we have investigated a group of small RNA molecules (microRNAs) that play an important role in gene expression regulation. We found that a group of microRNA molecules, called the miR-183/96/182 cluster, regulates the PAX6 gene that plays a crucial role in the proper development of the eye. Inhibition of these microRNA molecules leads to deregulation of the PAX6 gene and subsequent incorrect retinal morphogenesis. This group of microRNA molecules is also important for the proper development and function of other sensory organs, including the inner ear and olfactory epithelium.