 Martin Jinek

Martin Jinek coauthored a 2011 study explaining how Xrn1 recognizes an RNA end and couples hydrolysis to continued processing. The X-ray crystallography experiment used a truncated, catalytically altered construct bound to DNA; complementary biochemical experiments tested RNA degradation.^[ref]

This pairing of methods matters: a bound nucleic-acid segment can reveal contacts near an active site, while a degradation assay tests chemical function. Neither a static structure nor a single product measurement independently reveals every step in motion.

For an original structural example, take two hypothetical RNA-DNA hybrids with the same $20$ paired positions but different unpaired RNA extensions of $3$ and $7$ nucleotides. The RNA strands contain $23$ and $27$ nucleotides, respectively, while both DNA partners contain $20$. Equal paired-region length therefore does not mean equal accessibility of the $5^{\prime }$ end. This accounting illustrates a way of separating paired structure from end geometry, not the actual substrate dimensions used in the paper.

Jinek was also a coauthor of the 2012 demonstration of programmable Cas9 cleavage, together with Jennifer A. Doudna and other collaborators. That work connected guide RNA recognition with targeted DNA cleavage and showed that the guide functions could be combined in one RNA molecule.^[ref]