Structural basis for recognition of intron branchpoint RNA by yeast Msl5 and selective effects of interfacial mutations on splicing of yeast pre-mRNAs

Atomic contacts of Msl5-(KH-QUA2) with the branchpoint RNA. Stereo views of the RNA binding site, highlighting atomic contacts to the branchpoint segments U¹A²C³ (in A), C³U⁴A⁵ (in B), and A⁵A⁶C⁷ (in C). Amino acids and RNA are shown as stick models with beige and gray carbons, respectively. Waters are denoted by red spheres. Atomic contacts are indicated by dashed lines, in black for hydrogen bonds and magenta for van der Waals contacts.