このエントリーをはてなブックマークに追加
ID 20
file
creator
Yamaguchi, Nobuo
Michibata, Hitoshi
subject
Ascidian
Blood Cells
Chloride Channel
CLC-type
Gene Expression
H+-ATPase
Metal Accumulation
Vanadium
NDC
Chemistry
abstract
Ascidians, so-called sea squirts, can accumulate high levels of vanadium in the vacuoles of signet ring cells, which are one type of ascidian blood cell and are also called vanadocytes. In addition to containing high concentrations of vanadium in the +3 oxidation state, the proton concentrations in vanadocyte vacuoles are extremely high. In order to elucidate the entire mechanism of the accumulation and reduction of vanadium by ascidian vanadocytes, it is necessary to clarify the participation of anions, which might be involved as counter ions in the active accumulation of both vanadium and protons. We examined the chloride channel, since chloride ions are necessary for the acidification of intracellular vesicles and coexist with H+ ATPase. We cloned cDNA encoding a chloride channel from blood cells of a vanadium-rich ascidian, Ascidia sydneiensis samea. It encoded a 787-amino-acid protein, which showed striking similarity to mammalian ClC3/4/5-type chloride channels. Using a whole-mount in situ hybridization method that we developed for ascidian blood cells, the chloride channel was revealed to be transcribed in vanadocytes, suggesting its participation in the process of vanadium accumulation.
journal title
Comparative biochemistry and physiology. B, Biochemistry
volume
Volume 136
start page
91
end page
98
date of issued
2003
publisher
Elsevier Science Inc
issn
1096-4959
publisher doi
language
eng
nii type
Journal Article
HU type
Journal Articles
DCMI type
text
format
application/pdf
text version
author
rights
Copyright (c) 2003 Elsevier Science Inc
relation is version of URL
http://dx.doi.org/10.1016/S1096-4959(03)00175-1
department
Graduate School of Science