Guanine nucleotide-binding proteins (G proteins) are involved as a modulator or transducer in various transmembrane signaling systems. The beta and gamma chains are required for the GTPase activity, for replacement of GDP by GTP, and for G protein-effector interaction

Charcot-Marie-Tooth disease, dominant intermediate F

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. CMTDIF is characterized by onset around adolescence of slowly progressive distal muscle atrophy and weakness affecting the upper and lower limbs and resulting in steppage gait. There is distal sensory impairment with decreased reflexes. Nerve conduction velocities are variable, ranging from the demyelinating to the axonal range.