Nucleolin is the major nucleolar protein of growing eukaryotic cells. It is found associated with intranucleolar chromatin and pre-ribosomal particles. It induces chromatin decondensation by binding to histone H1. It is thought to play a role in pre-rRNA transcription and ribosome assembly. May play a role in the process of transcriptional elongation. Binds RNA oligonucleotides with 5'-UUAGGG-3' repeats more tightly than the telomeric single-stranded DNA 5'-TTAGGG-3' repeats. Identified in a IGF2BP1-dependent mRNP granule complex containing untranslated mRNAs (PubMed:17289661). Component of the SWAP complex that consists of NPM1, NCL/nucleolin, PARP1 and SWAP70 (By similarity). Component of a complex which is at least composed of HTATSF1/Tat-SF1, the P-TEFb complex components CDK9 and CCNT1, RNA polymerase II, SUPT5H, and NCL/nucleolin (PubMed:10393184). Interacts with AICDA (By similarity). Interacts with APTX (PubMed:15044383). Interacts with C1QBP (PubMed:21536856). Interacts with ERBB4 (PubMed:20858735). Interacts (via C-terminus) with FMR1 isoform 6 (via N-terminus) (PubMed:24658146). Interacts with GZF1; this interaction is important for nucleolar localization of GZF1 (PubMed:17674968). Interacts with NSUN2 (PubMed:17215513). Interacts with NVL (PubMed:21474449). Interacts (via N-terminus domain) with SETX (PubMed:21700224). Interacts (via RRM1 and C-terminal RRM4/Arg/Gly-rich domains) with TERT; the interaction is important for nucleolar localization of TERT (PubMed:15371412). Interacts with WDR46 (PubMed:23848194). Interacts with ZFP36 (PubMed:20221403). Interacts with LRRC34 (By similarity). Interacts with RRP1B (PubMed:19710015). Interacts with HNRNPU; this interaction occurs during mitosis (PubMed:21242313). Interacts with RIOK1; RIOK1 recruits NCL to PRMT5 for symmetrically methylation (PubMed:21081503). Interacts with ZBTB7B (By similarity). Interacts with MDK; this interaction promotes NCL clustering and lateral movements of this complex into lipid rafts leading to MDK internalization (PubMed:12147681). Interacts with HDGF (isoform 1) (PubMed:26845719). Interacts with ALKBH2. Localized in cytoplasmic mRNP granules containing untranslated mRNAs. Some glutamate residues are glycylated by TTLL8. This modification occurs exclusively on glutamate residues and results in a glycine chain on the gamma-carboxyl group (By similarity). Symmetrically methylated by PRMT5. Unlikely isoform. Aberrant splice sites.