Skip to main content
. 2020 Sep 1;10(9):2690–2704.

Figure 2.

Figure 2

Spliceosome complex. (1) U1 snRNP binds to the 5’ splice site (SS) of the pre-mRNA. The SR rich splicing factor, SRSF6 binds near the 5’SS, where it regulates splicing events. At the 3’ splice site the SR proteins SF1, SRSF2 and ZESF2 as well as the large subunit of the U2 auxiliary factor U2AF2, bind to the splice site. These splicing regulators bind to the branch point (BP) sequence and the polypyrimidine tract (PT). The smaller subunit of U2AF (U2AF1) binds to the 3’SS, forming a complex with U2AF2 and SRSF2. Another two RNA-binding proteins interact with the U2AF complex (2). Once the 3’ splice site is recognised the next group of splicing factors bind to the splice site, these include U2 snRNP, SF3A1, SF3B1, and SAP130. (3) The U4/U6 and U5 complex, together with PRFP8 are recruited and localize on the BP and PT regions. (4) This catalyses the release of the intron lariat and ligation of the exons.