histidine triad nucleotide binding protein 1
The HINT1 gene provides instructions for making a protein called histidine triad nucleotide-binding protein 1 (HINT1). The function of this protein is not clear. Laboratory studies show that the HINT1 protein has the ability to attach (bind) to certain types of molecules called nucleotides. HINT1 breaks down particular nucleotides through a process called hydrolysis. However, it is not known if the HINT1 protein performs the same reaction in the body or what effects it has.
Although the mechanisms are not completely understood, the HINT1 protein is involved in the nervous system. In nerve cells (neurons), HINT1 binds to signaling proteins called receptors that relay signals affecting nervous system function. HINT1 appears to stabilize the interaction of different receptors and regulate the effects of their signaling.
The HINT1 protein is also involved in programmed cell death (apoptosis), which occurs when cells are no longer needed. In addition, by blocking the activity of certain genes, HINT1 acts as a tumor suppressor, which means that it keeps cells from growing and dividing too rapidly or in an uncontrolled way.
At least nine mutations in the HINT1 gene have been found to cause autosomal recessive axonal neuropathy with neuromyotonia. This neurological condition affects the peripheral nerves, which connect the brain and spinal cord to muscles and to sensory cells that detect sensations such as touch. People with this condition typically have muscle weakness in the feet, legs, and hands and delayed relaxation of muscles after tensing (neuromyotonia). Some affected individuals have mildly impaired sensations.
The HINT1 gene mutations that cause this condition change single protein building blocks (amino acids) in the HINT1 protein. These changes reduce or eliminate the protein's ability to perform the hydrolysis reaction. Sometimes the altered protein is broken down prematurely. It is not clear how loss of functional HINT1 protein affects the peripheral nerves or leads to the signs and symptoms of this condition.
- adenosine 5'-monophosphoramidase
- histidine triad nucleotide-binding protein 1
- protein kinase C inhibitor 1
- protein kinase C-interacting protein 1