These DRACO proteins are (in the grand scheme of things) non-sequence (or indeed virus) specific, which is one of the reasons this is so exciting. They are specific in terms of the dsRNA binding domain they’re built with, although these domain may have a range of different sequences or secondary structures they can bind. The apoptotic response is triggered by the DRACO proteins crosslinking when two of them bind to the same fragment of dsRNA.
Put into slightly more straight forward terms, the apoptotic pathway is like a massive self destruct switch, which is triggered by a whole range of different things (viral infection, DNA damage, cancer signals etc). The body has evolved various mechanisms to detect dsRNA, as this is often a sign of viral infection. dsRNA doesn't occur naturally in mammals beyond ~10-25 nucleotides in length, while many viruses either have a dsRNA genome, or create long strands of dsRNA during their replication cycle, even if they do not have a long-term stable dsRNA genome. I’d imagine this provides a mechanism for DRACO proteins to target these non-dsRNA viruses. These DRACO proteins are simply a way to supercharge the body’s defences, increasing the cell's sensitivity to dsRNA.
My main concern would be relating to an immune response (any kind of recombinant protinaceous therapeutics is often risky), and also regarding administration and pharmacokinetics. Viruses are good at making lots of themselves, and may accumulate in different cell types, tissues or organs. Getting good, thorough coverage of the body may be a challenge. However, that said, any kind of “outside the box” therapeutics is always very welcome, especially where apoptosis is concerned, as it’s implicated in a wide range of diseases but is still relatively poorly understood.
I'm curious - I remember that over time viruses been incorporated into our DNA and rendered inert. Could these be targeted and damaged by the DRACO system? Or would they come within the ~10-25 nucleotide limit?
So the viruses incorporated into our DNA are in fact fragments of viral DNA, typically from reverse transcriptases. The DRACO proteins recognizes double stranded RNA (dsRNA), while reverse transcriptases incorporate dsDNA into our genome, and then use our own DNA replication proteins to make more of themselves! Crafty! The upshot of this, though, is that there's no dsRNA in our genome, so nothing the DRACO could detect.
It's like we store our genome on DVD, and some viruses use CDs. They're very similar, but it's not the "content" the DRACO proteins are looking at, but the medium. We have no way to make CDs, only viral proteins can do that, so if the DRACO proteins see CDs, there's probably a virus about.
Put into slightly more straight forward terms, the apoptotic pathway is like a massive self destruct switch, which is triggered by a whole range of different things (viral infection, DNA damage, cancer signals etc). The body has evolved various mechanisms to detect dsRNA, as this is often a sign of viral infection. dsRNA doesn't occur naturally in mammals beyond ~10-25 nucleotides in length, while many viruses either have a dsRNA genome, or create long strands of dsRNA during their replication cycle, even if they do not have a long-term stable dsRNA genome. I’d imagine this provides a mechanism for DRACO proteins to target these non-dsRNA viruses. These DRACO proteins are simply a way to supercharge the body’s defences, increasing the cell's sensitivity to dsRNA.
My main concern would be relating to an immune response (any kind of recombinant protinaceous therapeutics is often risky), and also regarding administration and pharmacokinetics. Viruses are good at making lots of themselves, and may accumulate in different cell types, tissues or organs. Getting good, thorough coverage of the body may be a challenge. However, that said, any kind of “outside the box” therapeutics is always very welcome, especially where apoptosis is concerned, as it’s implicated in a wide range of diseases but is still relatively poorly understood.