May facilitate 5' splice site recognition in the minor spliceosome. May be involved in interactions with components of the major spliceosome bound to the pyrimidine tract of an upstream U2-type intron. Part of the U11 snRNP, a component of the minor U12-type spliceosome. U11 and U12 snRNPs exist not only as monoparticles but also as a preformed U11/U12 di-snRNP complex. Interacts with CYP95, SCL28, SCL30, SCL30A, SCL33, SC35, SR30, SR34, RS31, RS40, RSZ21 and RS2Z33. Ubiquitous. Phosphorylated. Has no effect on the assembly of the protein into snRNP, but reduces the affinity for SR proteins. Truncated N-terminus.