Skip to main content
. 2016 Feb;36:48–57. doi: 10.1016/j.sbi.2015.12.005

Figure 4.

Figure 4

Structure of NTC and NTR. (a) The distribution of NTC and NTR components within the U2.U6.U5 spliceosome, comprising Body, Head, Arm I and Arm II domains. The Arm II, Head and Body regions are highlighted in red, green and blue, respectively. (b) The structures of NTC components, Prp19, Cef1 and Snt309 in the Arm II domain. Prp19 (red) forms a tetramer via its coiled-coil helices and U-box, and further interacts with Cef1 (purple) and Snt309 (pink). (c) Aquarius (green) and two superhelical proteins Syf1 (yellow) and Syf3 (dark green) form the Head domain protruding from the main body of the U2.U6.U5 spliceosomal complex. (d) The structures of NTC and NTR components in the Body region. Two proteins, Cwc2 (Cwf2) and Cwf19, shown in light and dark blue, respectively, are found close to the catalytic centre. Cwc2 was shown to interact with U6 snRNA ISL and induce an active conformation of the spliceosome's catalytic RNA elements [66]. In the U2.U6.U5 spliceosomal complex Cwc2 no longer interacts with U6 snRNA ISL. Cwf19 shows homology to S. cerevisiae Drn1 which interacts with the debranching enzyme Dbr1 [65•].