دانلود کتاب روش ها و پروتکل های رودوپسین – زیست شناسی مولکولی

Since the discovery of the first microbial rhodopsin—a light-driven proton pump bacteriorhodopsin (BR), a seven alpha helical membrane protein comprising the retinal, in 1971, BR was a major driver of groundbreaking developments in membrane protein research. BR studies stimulated important methodological developments in the fields like electron microscopy and membrane protein crystallization. However, before 1999 there were only several and only archaeal known rhodopsins, functioning as proton, chloride pumps, and also sensory rhodopsins. At the end of the twentieth century not many of us, if any at all, would imagine a new era of the rhodopsin world and its contributions to the applications in neuroscience. Not many enthusiasts were eager to continue working with these proteins. But nature plays tricks on us. A new microbial rhodopsin era started in 1999–2000 when the first bacterial rhodopsin, a proton pump, was discovered. Later it appeared that there are unexpectedly many rhodopsins and they are present in all the domains of life and even in viruses. It turned out (which is amazing) that they execute such a diversity of functions being “nearly the same.” However, in the late 1990s nobody could predict groundbreaking discoveries of other rhodopsin functions and among them, probably the most significant one, the discovery of channel rhodopsins (ChRs). For life science, it is the discovery of the proteins which are different from any known channels. For neuroscience, it was the biggest luck. ChRs are probably among two most important proteins in applications and opened a new field—optogenetics. A major core of optogenetics is microbial rhodopsins. Among over 10,000 currently identified potential rhodopsin genes only a few of the related proteins are characterized. This dramatically limits our knowledge of their molecular functions and mechanisms and biotechnological applications. Another limitation is that high-resolution structures and molecular mechanisms of the recently discovered rhodopsins (proteorhodopsin, sodium pump, inward proton pump) are yet unknown or, in the best case, only structures of the ground states are available. This is also the case of native channel rhodopsins which are the first and still major tool of optogenetics.