CNBP Human

CNBP is composed of seven zinc finger motifs of the CCHC type and a region abundant in arginine and glycine (RG/RGG) . These zinc finger domains enable CNBP to bind to specific sites on DNA and RNA, acting as a nucleic acid chaperone . This binding capability allows CNBP to regulate the transcription of various genes, including c-myc, wnt, and skeletal muscle chloride channel 1 (clc1) .

CNBP is involved in several critical biological functions:

1. Transcription Regulation: CNBP acts as a transcription regulator, essential for activating the innate immune response . It binds to specific motifs in the promoter regions of inflammatory cytokines, inducing their expression .
2. Development: CNBP is necessary for normal development before birth, particularly of muscles . It regulates cell proliferation and apoptosis during vertebrate organogenesis .
3. Disease Association: CNBP has been implicated in various human diseases, including myotonic dystrophy type 2 (DM2) and sporadic inclusion body myositis (sIBM) . The hyperactivation of the innate immune response associated with CNBP-mediated DM2 pathogenesis may confer susceptibility to immune-related diseases .

The CNBP gene contains a segment of four DNA building blocks (nucleotides) repeated multiple times, known as a tetranucleotide repeat . In most individuals, this sequence is repeated fewer than 26 times. However, in people with myotonic dystrophy type 2, the CCTG sequence can be repeated from 75 to more than 11,000 times . This mutation leads to the production of an altered version of messenger RNA, which traps proteins to form clumps within the cell, interfering with the production of many other proteins .

CNBP is a highly conserved protein, sharing more than 95% sequence identity among humans, chickens, rats, and mice . It is mainly localized to both the nuclei and cytoplasm of cells in mammals, amphibians, chickens, and fish .