Crystallization and preliminary X-ray analysis of the helicase domains of Vasa complexed with RNA and an ATP analogue.
The helicase fragment of Vasa was purified and its RNA-binding activity was examined by a UV cross-linking assay. The fragment was crystallized in complex with poly(U) RNA (U(10)) and a non-hydrolyzable analogue of ATP. The crystal belonged to space group P2(1), with unit-cell parameters a = 71.06, b = 142.35, c = 130.47 A, beta = 90.86 degrees. The cryocooled crystal diffracted to about 2.2 A using synchrotron radiation from station BL41XU at SPring-8.