EF-2_domain IV_snRNP domain is a part of 116kD U5-specific protein of the U5 small nucleoprotein (snRNP) particle, essential component of the spliceosome. The protein is structurally closely related to the eukaryotic translational elongation factor EF2. This domain has been also identified in 114kD U5-specific protein of Saccharomyces cerevisiae and may play an important role either in splicing process itself or the recycling of spliceosomal snRNP.