Nucleotide interaction regulates the chloride channel, ClC-4.
Published: 2004
Language: eng
Number of pages: 78
Description: ClC-4 is a member of the ClC family of chloride channels and is localized to the apical brush border membrane of intestinal enterocytes and to endosomes. Currently little is known about its regulation. A nucleotide requirement has been documented although the underlying mechanism has not been identified. We tested the hypothesis that ClC-4 could be phosphorylated by PKA or PKC. As well, we tested the hypothesis that ClC-4 directly binds nucleotides. Using purified peptides incorporating the intracellular N- and C-terminal regions, as well as lysates from ClC-4 transfected cell lines we showed that both peptides could be phosphorylated in a PKA-dependent manner, though the full-length protein could not. However, precipitation of ClC-4 with ATP Sepharose beads revealed that ClC-4 could bind to ATP in a magnesium-dependent manner and that this binding could be competitively inhibited. Future studies will determine the impact of this interaction on ClC-4 function in the plasma membrane and in endosomes.
Notes: Adviser:  Christine Bear.

Thesis (M.Sc.)--University of Toronto, 2004.

Electronic version licensed for access by U. of T. users.

Source: Masters Abstracts International, Volume: 43-03, page: 0761.

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