.... In addition, PIP2 also binds directly to the pre-rRNA processing factor fibrillarin (Fib), and co-localizes with nascent transcripts in the nucleolus. PIP2 binding to UBF and Fib modulates their binding to DNA and RNA, respectively. In conclusion, PIP2 interacts with a subset of Pol I transcription machinery...

... (RPN2109, GE Healthcare). For detection of nucleolar partners in lamin A/C and lamin B1 IP products, rabbit anti-fibrillarin (1/250, Abcam), rabbit anti-nucleophosmin (1/1000, Abcam) and rabbit anti-nucleolin (1/100, Abcam) were used. For determination of lamin protein content in the different nuclear...

... oocyte RNA polymerase I UBF fibrillarin rDNA transcription A characteristic feature of amphibian oocyte nuclei is the presence of multiple nucleoli which, unlike their somatic counterparts, are not attached to the chromosomes. Due to their extraordinary size these extrachromosomal nucleoli...

... of nucleolar proteins, BN46/51 bound to polypeptides of 44 kDa and 74 kDa. The 44 kDa component was identified as the Naegleria homologue of fibrillarin. BN46/51 bound specifically to the nucleoli of fixed mammalian cells, cells which lack a BN46/51 related polypeptide. When the JG4.1 and JG12.1 cDNAs were...

... discrete domains which are distinct from domains containing two of the major nucleolar antigens fibrillarin and RNA polymerase I. Within mature nucleoli the Ki-67 antigen is absent from regions containing RNA polymerase I and displays only partial co-localisation within domains containing either fib...

... of the hybrids by immunofluorescence microscopy and at the ultrastructural level was correlated with the distribution of two nucleolar proteins, nucleolin and fibrillarin. The U3 snRNA molecules persist through-out mitosis in close association with the nucleolar remnant. U3 snRNA is present in the prenucleolar...