Recognizes Nucleolin (NCL), the major nucleolar phosphoprotein of growing eukaryotic cells. NCL is located mainly in dense fibrillar regions of the nucleolus. It is found associated with intranucleolar chromatin and pre-ribosomal particles. Human NCL gene consists of 14 exons with 13 introns and spans approximately 11 kb. It has a predicted molecular weight of ~76 kDa with an apparent MW of 100-110 kDa, attributed to phosphorylation of its N-terminal domain. It induces chromatin decondensation by binding to histone H1. It is thought to play a role in pre-rRNA transcription and ribosome assembly.This MAb can be used to stain the nucleoli in cell or tissue preparations and can be used as a marker of the nucleoli in subcellular fractions. It produces a speckled pattern in the nuclei of cells of normal and malignant cells and may be used to stain the nucleoli of cells in fixed or frozen tissue sections. It can be used with paraformaldehyde fixed frozen tissue or cell preparations and formalin fixed, paraffin-embedded tissue sections. Primary antibodies are available purified, or with a selection of fluorescent CF® Dyes and other labels. CF® Dyes offer exceptional brightness and photostability. Note: Conjugates of blue fluorescent dyes like CF®405S and CF®405M are not recommended for detecting low abundance targets, because blue dyes have lower fluorescence and can give higher non-specific background than other dye colors.