Technical Data
Fibrillarin (rRNA 2'-O-methyltransferase Fibrillarin, D2870, LOT3, Nucleolar Protein 1, NOP1, Nop1p, U3 Small Nucleolar RNA-associated Protein NOP1, U3 snoRNA-associated Protein NOP1, YDL014W)
Nop1p was originally identified as a nucleolar protein of bakers yeast, Saccharomyces cerevisiae (accession P15646). The Nop1p protein is essential for yeast viability and is localized in the nucleoli. The human homolog of Nop1p is fibrillarin (accession P22087) a component of the nucleolar small nuclear ribonucleoprotein (snRNP) particle. The human fibrillarin gene is located on chromosome 19 (19q13.1). Fibrillarin proteins have been cloned and sequenced from several other species (Mouse, accession P35550, Xenopus accession P22232, C. elegans accession Q22053, and S. pombe accession P35551). The N terminal ~80 amino acids contain multiple copies based on the peptide RGG, and the remaining ~240 amino acids consist of the fibrillarin domain. A fibrillarin homolog has also been identified in the genome of the archean Methanococcus (accession NC_000909). This protein lacks the RGG rich N-terminal extension but is clearly homologous to the other sequences throughout all of the fibrillarin domain. The structure of this molecule has been determined and shown to consist of 2 extended b-sheets flanked by 4 a-helixes. Patients with the autoimmune disease scleroderma often have circulating autoantibodies to a 34kD protein which was subsequently found to be fibrillarin. For Nop1p/fibrillarin visualization in vertebrates, Drosophila and C. elegans and other species we recommend 031359.

Suitable for use in Immunofluorescence, Immunoprecipitation and Western Blot. Other applications not tested.

Recommended Dilution:
Immunofluorescence: 1:2000-1:20,000
Immunoprecipitation: 2-4ul for an amount of lysate derived from 5 OD600 units of yeast culture.
Western Blot: For yeast protein samples, use diluted 1:10,000 (cell lysates) to 1:25,000 (nuclear fractions), followed by chemiluminescent detection (ECL). For other (non-ECL) Western detection methods, try diluted 1:1000-1:5000.
Optimal dilutions to be determined by the researcher.

Storage and Stability:
May be stored at 4C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20C. Aliquots are stable for 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
500ul4C Do Not FreezeBlue IceMouse
Not determined
Yeast nuclear preparations
Sterile-filtered cell culture fluid
Supplied as a liquid in 10mM sodium azide.
Recognizes Nop1p. Does not crossreact with fibrillarin in other species, but is an excellent marker of the nucleolus of yeast cells.
Intended for research use only. Not for use in human, therapeutic, or diagnostic applications.
1. Ochs RL, Lischwe MA, Spohn WH, Busch H. Fibrillarin: a new protein of the nucleolus identified by autoimmune sera. Biol Cell 54:123-133 (1985).

2. Aris JP and Blobel G. Identification and characterization of a yeast nucleolar protein that is similar to a rat liver nucleolar protein. J. Cell Biol. 107:17-31 (1988).

3. Tsang CK, Bertram PG, Ai W, Drenan R, Zheng XF. Chromatin-mediated regulation of nucleolar structure and RNA Pol I localization by TOR. EMBO J. 22:6045-56 (2003).

4. Porter SE, Penheiter KL, Jaehning JA. Separation of the Saccharomyces cerevisiae Paf1 Complex from RNA Polymerase II Results in Changes in Its Subnuclear Localization. Eukaryotic Cell 4:209-220 (2004).

5. Hochwagen A, Tham W, Brar G, Amon, A. The FK506 Binding Protein Fpr3 Counteracts Protein Phosphatase 1 to Maintain Meiotic Recombination Checkpoint Activity Cell 122:861873 (2005).