Comment by jjtheblunt | Hacker News Reader

Comment by jjtheblunt | Hacker News Reader

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Isn't the repair work that of the RNA ligases, whose particular versions for humans are first mentioned here?

> "In order to fulfill their diverse functions in the cell, RNAs often need to be chemically modified after their creation or repaired after damage," explains Andreas Marx, professor of organic and cellular chemistry at the University of Konstanz.

> One chemical reaction that plays a role here is the three-step linking (ligation) of two RNA strands at their respective opposite ends. This reaction is triggered by specialized enzymes called RNA ligases and is present in all forms of life, from viruses to fungi and plants. In vertebrates, including humans, such RNA ligases had yet to be identified.

> An interdisciplinary research team from Konstanz has now discovered the first human RNA ligase of this type, the protein C12orf29."

Ah. Ok. I see why you would infer that.

But it's an inference -- an assumption that human ligases will do what ligases do in other species and that's not what the actual research shows, at least not that the article indicates.

We've just discovered these. They are investigating what they do. Their investigation shows they protect against oxidative stress, which is significant.

I generally agree with your assessment.

I skimmed the paper and there really isn't any direct evidence that it's a "repair mechanism" beyond the apparent effects of knocking out the gene: cells die faster, and degradation of ribosomal RNA is faster.

The presumed mechanism here would be oxidative stress->damage to rRNA->reduced protein production/increased error rate in proteins->cell is not happy, with the RNA ligase playing the role of repairing localized damage caused by stress thus allowing the cell to continue at its normal rate.

There also isn't any strong evidence that this system resembles the ones seen in viruses and bacteria. There are many RNA ligases that have many different roles and the variations aren't shared between all kingdoms of life.

Thank you. That's helpful.

I have lousy eyesight. I sometimes just fail to find what I'm looking for and it's important to me to understand this stuff.

Agreed on all counts, though it's important to note that this protein has bacterial homologs that almost definitely have the same function (5'-3' RNA ligase activity).

I think you're right that they're just (at this point) making a conjecture, which is incongruent with the title.

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