Nucleolin

The human NCL gene is located on chromosome 2 and consists of 14 exons with 13 introns and spans approximately 11kb. Intron 11 of the NCL gene encodes a small nucleolar RNA, termed U20.^[7]

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.

Nucleolin is also able to act as a transcriptional coactivator with Chicken Ovalbumin Upstream Promoter Transcription Factor II (COUP-TFII).^[8]

Midkine and pleiotrophin bind to cell-surface nucleolin as a low affinity receptor. This binding can inhibit HIV infection.^[9][10]

Nucleolin at the cell surface is the receptor for the respiratory syncytial virus (RSV) fusion protein.^[11] Interference with the nucleolin–RSV fusion protein interaction has been shown to be therapeutic against RSV infection in cell cultures and animal models.^{[12][13][14][15]}

Nucleolin has been shown to interact with: