Biophysical meeting in San Diego

Attending conferences is an important part of the scientific research. It represent the  the possibility to share information even before they reached definitive publishable results, to be updated about the most recent discoveries directly by the authors, to do networking and have informal discussions with people who do the same research as you, but differently, and last but not least... it push you to travel around the world! (Incidentally, from Osaka the shortest route is via the Hawaii, where I will stop by few days in the way back).

As part of my project, I am going to San Diego (CA) to attend the Biophysical Society Annual Meeting, a five-day meeting with about 5,000 attendees,  500 speakers and 600 daily poster presentations, included mine.

I will present an analysis about the calcium gradients in resting muscle cells generated by the leakage of the calcium-release channel. The channel (RyR) functionally opens during action potentials to release big amounts of calcium ions which triggers the muscle contraction activating the thin filament. However, even in resting muscle a small but not negligible amount of calcium is released both by RyR and also by the structures which re-uptake the calcium after the contraction, to induce relaxation. This leakage has been shown, recently, to be much higher, up to 15 times, in a particular mutation which is studied since 15 years in Padova University. The mutation ablate the major calcium buffer in the calcium stores in the cell, and is of interest because it is related to the malignant hyperthermia, which could lead to death in some patients treated with anaesthetic. 

The interest in studying the gradients of Calcium in quiescent muscle resides in the data collected in these last 15 years of analysis which constantly shown an increased mitochondrial calcium content (recently confirmed by independent analysis) without the expected basal calcium concentration in the cytosol, where the mitochondria are immersed and with which they are in equilibrium.  We hypothesize that the gradient generated by the leak, which is not appreciable with the calcium probes normally used to estimate the calcium concentration, because they can sense only the average concentration.

Shortly (not enough maybe) the results suggests that the gradient is indeed elevated enough to generate a different behavior in mitochondria, while having the same free calcium concentration in the surrounding media.


After the meeting, I will post here the poster with the description, as well as why this is important for the super-relaxed state and the thick filament activation. 
However, to keep the blog more informal, in the next days I will also upload some pictures from San Diego! And Hawaii!!!

Haloa!




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