[Hybridization of low molecular weight nuclear RNA with nuclear RNA and DNA restriction fragments]

Blot hybridization of 125I or 32P labeled 4.5S, U1 or U2 RNAs with EcoRI, HindIII, BamHI or SalG1 restriction fragments of high molecular weight DNA was performed. All these RNAs hybridized with fragments of ribosomal DNA and with 5.55-kb BamHI lines of rat. U1 ind 4.5S RNAs hybridized also with 3.6-kb HindIII lines. 125I labeled U1 RNA was hybridized with nuclear RNA in formamide. The hybrid molecules were formed which migrate in polyacrylamide gel as a broad peak slower than 28S rRNA. Our data indicate that snRNAs may participate in processing and/or splicing of hnRNA and in some other still poorly understood processes.