Referenced in: none

Automatically associated channels: Kv1.3 , Slo1

Title: 7DHC-induced changes of Kv1.3 operation contributes to modified T cell function in Smith-Lemli-Opitz syndrome.

Authors: András Balajthy, Sándor Somodi, Zoltán Pethő, Mária Péter, Zoltan Varga, Gabriella P Szabó, György Paragh, Laszlo Vigh, Gyorgy Panyi, Péter Hajdu

Journal, date & volume: Pflugers Arch., 2016 Jun 17 , ,

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/27315086

Abstract
In vitro manipulation of membrane sterol level affects the regulation of ion channels and consequently certain cellular functions; however, a comprehensive study that confirms the pathophysiological significance of these results is missing. The malfunction of 7-dehydrocholesterol (7DHC) reductase in Smith-Lemli-Opitz syndrome (SLOS) leads to the elevation of the 7-dehydrocholesterol level in the plasma membrane. T lymphocytes were isolated from SLOS patients to assess the effect of the in vivo altered membrane sterol composition on the operation of the voltage-gated Kv1.3 channel and the ion channel-dependent mitogenic responses. We found that the kinetic and equilibrium parameters of Kv1.3 activation changed in SLOS cells. Identical changes in Kv1.3 operation were observed when control/healthy T cells were loaded with 7DHC. Removal of the putative sterol binding sites on Kv1.3 resulted in a phenotype that was not influenced by the elevation in membrane sterol level. Functional assays exhibited impaired activation and proliferation rate of T cells probably partially due to the modified Kv1.3 operation. We concluded that the altered membrane sterol composition hindered the operation of Kv1.3 as well as the ion channel-controlled T cell functions.