Isolation and characterization of three rat U3 RNA pseudogenes colinear with U3 RNA.

Isolation and characterization of three rat U3 RNA pseudogenes colinear with U3 RNA.

Three different 15-kilobase rat genomic clones that contained sequences colinear with U3 RNA were isolated. These inserts hybridized only to U3 RNA in a mixture of total cellular 4-8 S RNA labeled in vivo which showed that genes or pseudogenes for most other small RNAs were absent in these U3 DNA clones. DNA sequence analysis showed that the three subcloned genes contained full-length U3-coding...

Nuclear retention elements of U3 small nucleolar RNA.

The processing and methylation of precursor rRNA is mediated by the box C/D small nucleolar RNAs (snoRNAs). These snoRNAs differ from most cellular RNAs in that they are not exported to the cytoplasm. Instead, these RNAs are actively retained in the nucleus where they assemble with proteins into mature small nucleolar ribonucleoprotein particles and are targeted to their intranuclear site of ac...

Nucleolar localization elements of Xenopus laevis U3 small nucleolar RNA.

The Nucleolar Localization Elements (NoLEs) of Xenopus laevis U3 small nucleolar RNA (snoRNA) have been defined. Fluorescein-labeled wild-type U3 snoRNA injected into Xenopus oocyte nuclei localized specifically to nucleoli as shown by fluorescence microscopy. Injection of mutated U3 snoRNA revealed that the 5' region containing Boxes A and A', known to be important for rRNA processing, is not ...

Genes for Xenopus laevis U3 small nuclear RNA.

Genomic Southern blots showed there are only 14 to 20 copies of U3 snRNA genes per somatic genome in Xenopus laevis, unlike the highly repetitive, tandem arrangement of other snRNA genes in this organism. Sequencing of two U3 snRNA genes from lambda clones of a genomic library revealed striking similarity upstream, but much more divergence downstream. Consensus motifs common to other U snRNA ge...

RNA Isolation (Small RNA Extraction). Fatemeh Mehrpooyan*