Higher Expression of TRPM7 Channels in Murine Mature B Lymphocytes than Immature Cells
The Korean Journal of Physiology and Pharmacology
; : 69-75, 2005.
Article
в En
| WPRIM
| ID: wpr-727667
Ответственная библиотека:
WPRO
ABSTRACT
TRPM7, a cation channel protein permeable to various metal ions such as Mg2+, is ubiquitously expressed in variety of cells including lymphocytes. The activity of TRPM7 is tightly regulated by intracellular Mg2+, thus named Mg2+-inhibited cation (MIC) current, and its expression is known to be critical for the viability and proliferation of B lymphocytes. In this study, the level of MIC current was compared between immature (WEHI-231) and mature (Bal-17) B lymphocytes. In both cell types, an intracellular dialysis with Mg2+-free solution (140 mM CsCl) induced an outwardly-rectifying MIC current. The peak amplitude of MIC current and the permeability to divalent cation (Mn2+) were several fold higher in Bal-17 than WEHI-231. Also, the level of mRNAs for TRPM7, a molecular correspondence of the MIC channel, was significantly higher in Bal-17 cells. The amplitude of MIC was further increased, and the relation between current and voltage became linear under divalent cation-free conditions, demonstrating typical properties of the TRPM7. The stimulation of B cell receptors (BCR) by ligation with antibodies did not change the amplitude of MIC current. Also, increase of extracellular [Mg2+]c to enhance the Mg2+ influx did not affect the BCR ligation-induced death of WEHI-231 cells. Although the level of TRPM7 was not directly related with the cell death of immature B cells, the remarkable difference of TRPM7 might indicate a fundamental change in the permeability to divalent cations during the development of B cells.
Key words
Полный текст:
1
База данных:
WPRIM
Основная тема:
Permeability
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RNA, Messenger
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B-Lymphocytes
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Lymphocytes
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Cations, Divalent
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Cell Death
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Dialysis
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Precursor Cells, B-Lymphoid
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Ions
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Ligation
Язык:
En
Журнал:
The Korean Journal of Physiology and Pharmacology
Год:
2005
Тип:
Article