U1 small nuclear RNA variant 3 (RNU1-3)

U1 small nuclear RNA variant 3 (RNU1-3) is a member of the U1 snRNA family, which are non-coding RNAs forming core components of the U1 small nuclear ribonucleoprotein (U1 snRNP)[7][5][10]. The U1 snRNP mediates recognition of the 5′ splice site at exon-intron boundaries of pre-mRNA, initiating spliceosome assembly and intron excision during precursor mRNA processing[7][1][4][6]. U1 snRNA exists in several variants, including RNU1-3, which may differ in sequence but share the canonical function of base-pairing with the 5′ splice site[5]. U1 snRNAs are highly conserved, form complexes with proteins (U1-70K, U1-A, U1-C, Sm proteins), and are critical for accurate gene expression[6][7]. Some variants, such as RNU1-3, are not as well characterized; their ability to form functional snRNPs and participate in splicing is less efficient compared to canonical U1 snRNA[5]. Mutations or dysfunction in U1 snRNA processing or splicing can contribute to disease, particularly those involving splicing errors (e.g., cancer)[1]. U1 snRNA and its variants are classified as small nuclear RNAs, not as therapeutic targets, enzymes, receptors, or transporters. There are no well-documented drugs directly targeting RNU1-3, nor safety concerns or biomarker roles established for patient selection. Many variants have limited functional annotation beyond their sequence and structural existence, and the target name "RNA, U1 small nuclear 3" appears to be a variant name rather than a canonical molecular target, hence this entry is best described as a sequence variant of a non-coding RNA with basic research interest[5].

Other names

HSD4RNU1G3RNU1-3RNA, U1G3 small nuclear

No drugs with defined mechanisms targeting this molecule; experimental variants may modulate splicing by base-pairing with splice sites