National security, unlocked. Each Thursday, host Mary Louise Kelly and a team of NPR correspondents discuss the biggest national security news of the week. With decades of reporting from battlefields ...

miRNAs are short, noncoding RNA molecules, 16–29 nucleotides long, that modulate gene expression by base-pairing with the 3′ untranslated region of their target mRNAs. Depending on the degree of ...