GJB1

This gene encodes a member of the gap junction protein family. The gap junction proteins are membrane-spanning proteins that assemble to form gap junction channels that facilitate the transfer of ions and small molecules between cells. According to sequence similarities at the nucleotide and amino acid levels, the gap junction proteins are divided into two categories, alpha and beta. Mutations in this gene cause X-linked Charcot-Marie-Tooth disease, an inherited peripheral neuropathy. Alternatively spliced transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Oct 2008]

Gap Junction Protein Beta 1

One gap junction consists of a cluster of closely packed pairs of transmembrane channels, the connexons, through which materials of low MW diffuse from one cell to a neighboring cell.

Cell-cell signaling Source: GO_Central
Epididymis development Source: Ensembl
Gap junction assembly Source: Reactome
Nervous system development Source: ProtInc
Purine ribonucleotide transport Source: Ensembl

Cell membrane; Gap junction

Charcot-Marie-Tooth disease, X-linked dominant, 1 (CMTX1):
A form of Charcot-Marie-Tooth disease, a disorder of the peripheral nervous system, characterized by progressive weakness and atrophy, initially of the peroneal muscles and later of the distal muscles of the arms. Charcot-Marie-Tooth disease is classified in two main groups on the basis of electrophysiologic properties and histopathology: primary peripheral demyelinating neuropathies characterized by severely reduced motor nerve conduction velocities (NCVs) (less than 38m/s) and segmental demyelination and remyelination, and primary peripheral axonal neuropathies characterized by normal or mildly reduced NCVs and chronic axonal degeneration and regeneration on nerve biopsy. CMTX1 has both demyelinating and axonal features. Central nervous system involvement may occur.
Dejerine-Sottas syndrome (DSS):
A severe degenerating neuropathy of the demyelinating Charcot-Marie-Tooth disease category, with onset by age 2 years. Characterized by motor and sensory neuropathy with very slow nerve conduction velocities, increased cerebrospinal fluid protein concentrations, hypertrophic nerve changes, delayed age of walking as well as areflexia. There are both autosomal dominant and autosomal recessive forms of Dejerine-Sottas syndrome.

Cytoplasmic: 1-22
Helical: 23-45
Extracellular: 46-75
Helical: 76-95
Cytoplasmic: 96-130
Helical: 131-153
Extracellular: 154-191
Helical: 192-214
Cytoplasmic: 215-283