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I'm very pleased to report that that the SENS Research Foundation project on mitochondrial allotopic expression (MitoSENS) that was crowdfunded at Lifespan.io this time last year has achieved success. The two target mitochondrial genes have been moved to the cell nucleus, and suitably altered so that the proteins produced return to the mitochondria. This means that cells so treated are immune to age-related damage to those two genes in the mitochondrial genome: they will still construct and make normal use of the proteins encoded in those genes as though nothing happened. Given that mitochondrial DNA damage is an important contribution to the aging process, progress on this front is very welcome.

The crowdfunded work was the final sprint at the end of a years-long project conducted with minimal funding, and it is great to see success. Congratulations are due to the researchers involved. There are thirteen mitochondrial proteins in total that are thought to be all that is needed to move into the nucleus. Allotopic expression of one other mitochondrial gene is solidly complete, and is the basis for the therapies under development at Gensight. Another two genes are somewhere in the middle of the process in the SENS Research Foundation network of researchers. This leaves a further eight genes to go. As ever, this is work that is in search of much greater funding: the researchers are always ready to go, and the more that we can do to help deliver that funding, the sooner we'll see rejuvenation therapies in the clinic.

Note that you may need to click the updates tab on the fundraiser page in order for the updates to load:

Hi everyone, it's been an amazing few months. In short, we have been tremendously successful in our efforts to rescue a mutation in the mitochondrial genome! Essentially we've shown that we can relocate both ATP6 and ATP8 to the nucleus and target the proteins to the mitochondria. We can show that the proteins incorporate into the correct protein complex (the ATPase) and that they improve function resulting in more ATP production. Finally, we show that the rescued cells can survive and grow under conditions which require mitochondrial energy production while the mutant cells all die.

We have finished writing up our results and submitted them for review and publication. It may take a while for our results to be published (the peer review process can be lengthy) but as soon as it is I'll post an update here so you can see the full paper. We have also started the project that you helped us get to our stretch goal on. We have made all the combinations of mitochondrial targeting sequences with ATP6 that we proposed and are now working on testing them. I'll let you know when we know more. Thank you so much for your support!

Link: https://www.lifespan...roject/#updates

View the full article at FightAging

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From the 2016 SENS Annual Report. I found it a readable version for non specialists of a great scientific result and most importantly a proof point of SENS:

 

"Engineering New Mitochondrial Genes to Restore Mitochondrial Function

SENS Research Foundation Research Center
Principal Investigator: Matthew O’Connor
Research Team: Amutha Boominathan, Bhavna Dixit, Kathleen Powers, Shon Vanhoozer

Free radicals derived from our energy-producing mitochondria can mutate the organelle’s DNA, leading to deletions of large stretches of the mitochondrial genome. These deletion mutations
prevent the mitochondria from building various pieces of the electron transport chain (ETC), with which mitochondria generate most cellular energy. The accumulation of deletion-mutation containing cells is a significant consequence of aging, and is implicated in age-related disease as well as in several currently incurable and extremely debilitating inherited mitochondrial disorders. The rescue of mitochondrial DNA mutations therefore has tremendous potential for restoring the health of aging people and treating the victims of inherited mitochondrial disease.
A potential rejuvenation biotechnology to recover ETC function is the allotopic expression of functional mitochondrial genes: placing “backup copies” of all of the protein-coding genes of the
mitochondria in the “safe harbor” of the nucleus, thereby giving the mitochondrion all of the proteins it needs to continue producing energy normally even when the original mitochondrial copies have been mutated. However, demonstration of efficient functional rescue via allotopic expression has long been a research challenge. This year, the SRF MitoSENS team reported a tremendous success: for what they believe is the first time, they have used allotopic expression to rescue the complete loss of a mitochondrially-encoded protein in a mammalian cell. Achieving this landmark success required several key steps. First, because of its ancient evolutionary history as a separate organism, the mitochondrial genome actually uses a different genetic code from the one used by the genes in the cell’s nucleus, so the “lettering” of the mitochondrial genes had to be “rewritten” to function in the nucleus. Next, in order to allow the proteins that the
allotopically-expressed genes encode to enter into the mitochondria, the team had to engineer in versions of the targeting sequences that permit such entry from the proteins that are naturally
encoded in the nucleus but destined for the mitochondria. And finally, they had to demonstrate in ways that would finally convince a skeptical scientific community that their engineered proteins
could achieve the functional rescue of mitochondrial mutations. For the proof-of-concept, the SRF group has focused on the smallest mitochondrially-encoded protein, a component of the last Complex of the ETS called ATP8. To demonstrate rescue, they used cells derived from a patient who suffered from a rare mutation in the ATP gene that completely prevented the production of the ATP8 protein. However, the patient’s original cells contained a mixture of mitochondria, only a subset of which carried this otherwise-fatal mutation. So in order to decisively prove the effectiveness of allotopic expression, the group had to perform additional work to make a derivative completely free of wild-type ATP8 genes, so that there would not be any competing endogenous ATP8 protein that might otherwise be thought responsible for the rescue of the cells. A publication in the prestigious scientific journal Nucleic Acids Research announced their success in the fall of 2016. The results show that their targeted and recoded ATP8 protein can be expressed from the nucleus, turned into protein in both normal and mutant cells, and efficiently targeted to the mitochondria. Furthermore, they can demonstrate functional rescue of the null cells. Under conditions where mutant cells die for lack of ability to produce energy, the cells with engineered allotopically-expressed proteins were able to survive and replicate. Drilling down further, they additionally show that the allotopically-expressed protein is successfully localized to Complex V of the ETS where it belongs, and that mitochondria from such cells consume oxygen, which is required for the ETC to produce energy but which does not occur in mutant cells lacking the allotopically expressed genes. Lastly, they show that the Complex V of mitochondria from such cells is capable of recharging ATP, the cell’s energy currency. In addition to ATP8, the SRF MitoSENS team has further demonstrated expression and targeting of a second re-engineered protein, ATP6, simultaneously in the same cells (which are also deficient – though not completely lacking – in ATP6 protein). Adding allotopically-expressed ATP6 to ATP8 in such cells has further enhanced the benefits of ATP8 alone on most of the measures noted above. And most importantly, it is proof-of-concept that ATP8 is not a special case: other mitochondrially encoded proteins can simultaneously be expressed from the nucleus, targeted to and imported into the mitochondria, and function appropriately in the ETC. We are hopeful that these results are an important step towards proof-of-concept of future allotopic expression gene therapies." (bold mine)