Abstract
This chapter focuses on molecular changes in subunits of potassium channels, which are relevant to various disorders. Numerous studies on the diversity of amino acid sequences of potassium channels have been conducted. Since over 50 mammalian genes encode the chief subunits of potassium channels, it is difficult to carry out the research. Each of these genes can undergo a lot of multiple mutations which significantly influence potassium channel function. If we take into consideration all the changes, the functional diversity of the channels extends radically. In addition, these genes undergo RNA processing, such as alternative splicing, which leads to multiplication of protein products for each gene. As a result, the number of different mammalian principal subunits increases to over a few hundred. Considering other changes arising in the processes of gene transcription, RNA processing, post-translational modification and protein degradation, the total number of different functional potassium channel subtypes is probably much higher.
In the first part of this chapter we would like to present the diversity of mutations in genes coding for potassium channels as well as their influence related to the most important defects, diseases and functional impairments (from the clinical point of view). We will rather focus on novel information in this field, published during the last few years. In the following sections, we will describe other modifications that influence potassium channels, such as alternative splicing, RNA editing and posttranslational modifications.
Keywords: Potassium chanels mutations, Alternative splicing, Gene transcription, RNA editing, posttranslational modifications, Romano-Ward Syndrome (RWS), Lange-Nielsen Syndrome (JLNS), Missense mutation, Benign Familial Neonatal Convulsions (BFNC), Hypokalemic Periodic Paralysis (TPP)
