Scientists from Tokyo University of Science have shed light on how various molecules are recruited in endocytosis, a cellular process of bringing in different types of materials from the outside.
The results suggest key regulatory functions of the yeast Eps15-like protein Pan1p. The findings provide important insights into the process, which is central to disease prevention.
In endocytosis, a part of the cell membrane invaginates and buds off into the cytoplasm as a vesicle with the engulfed molecule inside. Endocytosis serves several cellular functions such as nutrient intake and the recycling of neurotransmitters.
A poorly understood process
Clathrin-mediated endocytosis is an important type of endocytosis in which the internalised vesicles are coated with the protein, clathrin. Until now, the recruitment processes of the molecular players to the site and the switch between the early and late phases were not well understood.
The yeast protein Pan1p (human EPS15) is known to anchor several proteins (scaffolding protein) during the later stages of yeast clathrin-mediated endocytosis.
Findings to aid therapy development
A team of scientists from Austria and Japan, led by Prof Jiro Toshima (Tokyo University of Science) and Prof Junko Y Toshima (Tokyo University of Technology) conducted a set of experiments where the location of Pan1p was altered to peroxisomes from the cell membrane.
“The new mechanism of cellular endocytosis revealed in this study not only elucidates the molecular mechanisms but will also lead to the development of therapeutic methods,” hopes Prof Toshima.
Their experiments revealed that Pan1p plays important regulatory functions in the progression of endocytic process. It also has a crucial role in actin polymerisation and drives the recruitment of a range of actin nucleation promoting factors.
Read the original paper: ‘Eps15/Pan1p is a master regulator of the late stages of the endocytic pathway’ in the Journal of Cell Biology.