This is a structure of the Asterix/Gtsf1 protein. Asterix/Gtsf1 helps immobilize so-called "jumping genes" in germ cells, a type of cell important for sexual reproduction. CSHL Professor & HHMI Investigator Leemor Joshua-Tor and a research investigator in her lab, Jonathan Ipsaro, used two different biophysical techniques, cryo-EM and NMR, to develop their model. In this NMR structure, the purple helix binds to a tRNA, a special class of RNA, which is speculated to escort it to a jumping gene. The blue surface of the protein is positively charged, which helps it bind to negatively charged RNA molecules. The red area on the right is negatively charged.