Coilin antibody [pdelta]

The description of specific intranuclear structures known today as Cajal bodies was first published in 1903 by the neuro-cytologist Ramon-y-Cajal. He observed that neurons stained with silver contained spherical structures of around 0.5 micron in diameter that were often associated with nucleoli and called them nucleolar accessory bodies. Later, the same bodies were called coiled bodies since when these structures were viewed by electron microscopy, they resembled a tangle of coiled threads. It was found that patients with autoantibodies against coiled bodies recognize a protein of 80 kDa termed p80-coilin. Using these antibodies, coiled bodies were identified in plants, flies, frogs, birds, and mammals. The gene encoding p80-coilin has been cloned and sequenced. It contains two nuclear localization sequences (NLS) (at amino acid 107-112 and 181-198) and several serine residues that are phosphorylated in vivo. Mutating Serine-202 to Aspartate causes the disappearance of coiled bodies and a redistribution of coilin to intranucleolar domains. Nuclear antigens shown to colocalize with p80 coilin in Cajal bodies include basal transcription factors, cell cycle factors (cdks), splicing snRNPs and nucleolar factors including snoRNPs.