The Evolutionary Choice of Cellular Signals: Why Calcium
Prof. Ernesto Carafoli
DATE: 31st July 2020 (GMT +8)
TIME: 6:00 – 7:00 pm (Time in China)
Calcium carries messages to virtually all important functions of cells. Although already active in unicellular organisms its role has become universally important after the transition to multicellular life.
In this lecture, we explore how calcium ended up in this privileged position. Most likely Its unique coordination chemistry has been a decisive factor as it makes its binding by complex molecules particularly easy, even in the presence of large excesses of other cations, e.g. magnesium.
Its free concentration within cells can thus be maintained at the very low levels demanded by the signalling function. A large cadre of proteins has evolved to bind or transport calcium. They all contribute to buffering it within cells, but a number of them also decode its message for the benefit of the target. The most important of these “calcium sensors” are the EF-hand proteins. Calcium is an ambivalent messenger: while essential to the correct functioning of cell processes if not carefully controlled spatially and temporally within cells it generates variously severe cell dysfunctions, and even cell death.
Brini, M., et al., (2013). Chapter 4. Calcium in health and disease. In: A. Sigel, H. Sigel, and R.K.O. Sigel (Eds.), Interrelations between Essential 81 Metal Ions and Human Diseases, Metal Ions in Life Sciences, 13: 81–137. DOI 10.1007/978-94-007-7500-8_4.