Involved in modulating alternative pre-mRNA splicing with either 5' distal site activation or preferential use of 3' proximal site. In case of infection by Herpes simplex virus (HSVI), may act as a splicing inhibitor of HSVI pre-mRNA. . This is the function of ARL6IP4 (ARF like GTPase 6 interacting protein 4, ENSG00000182196).