Thread

1. kens · 1790113398 · focus · HN ↗

   The details of UV damage are interesting. You can think of DNA as a sequence of four letters: C, G, A, and T. If there are two neighboring T's, UV can move a bond, linking the two T's together (i.e. thymine dimerization). If you're in the sun, each skin cell gets 50-100 of these pairs created per second (which is much higher than I expected). Enzymes fix most of these errors, but sometimes the errors will cause problems during DNA replication and you can end up with mutations.

   Details: <a href="https:&#x2F;&#x2F;pdb101.rcsb.org&#x2F;motm&#x2F;91" rel="nofollow">https:&#x2F;&#x2F;pdb101.rcsb.org&#x2F;motm&#x2F;91

   1. pazimzadeh · 1790119654 · focus · HN ↗

      I wish people would stop saying UV without clarifying what wavelength they mean. Damage from UVA and UVB is very different.

      UVB light can promote DNA repair pathways:

      Enhancement of UVB-induced DNA damage repair after a chronic low-dose UVB pre-stimulation

      <a href="https:&#x2F;&#x2F;www.sciencedirect.com&#x2F;science&#x2F;article&#x2F;abs&#x2F;pii&#x2F;S1568786417301635" rel="nofollow">https:&#x2F;&#x2F;www.sciencedirect.com&#x2F;science&#x2F;article&#x2F;abs&#x2F;pii&#x2F;S15687...

      UVA can slow down repair of damage from UVB:

      Long-wavelength UVA enhances UVB-induced cell death in cultured keratinocytes: DSB formation and suppressed survival pathway

      <a href="https:&#x2F;&#x2F;pubmed.ncbi.nlm.nih.gov&#x2F;33978941&#x2F;" rel="nofollow">https:&#x2F;&#x2F;pubmed.ncbi.nlm.nih.gov&#x2F;33978941&#x2F;

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