Centrin controls the activity of the ciliary reversal-coupled voltage-gated Ca channels Ca-dependently

نویسندگان

  • Kohsuke Gonda
  • Kazunori Oami
  • Mihoko Takahashi
چکیده

In Paramecium, ciliary reversal is coupled with voltage-gated Ca 2+ channels on the ciliary membrane. We previously isolated a P. caudatum mutant, cnrC, with a malfunction of the Ca 2+ channels and discovered that the channel activity of cnrC was restored by transfection of the P. caudatum centrin (Pccentrin1p) gene, which encodes a member of the Ca 2+-binding EF-hand protein family. In this study, we injected various mutated Pccentrin1p genes into cnrC and investigated whether these genes restore the Ca 2+ channel activity of cnrC. A Pccentrin1p mutant gene lacking Ca 2+ sensitivity of the third and fourth EF-hands lost the ability to restore the channel function of cnrC, and mutation of the fourth EF-hand caused more serious impairment than mutation of the third EF-hand. Moreover, a Pccentrin1p gene lacking the N-terminal 34-amino acid sequence also lost the ability to restore the channel activity. Native-PAGE analysis demonstrated that the N-terminal sequence is important for the Ca 2+-dependent structural change of Pccentrin1p. These results demonstrate that Pccentrin1p Ca 2+-dependently regulates the Ca 2+ channel activity in vivo.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Centrin controls the activity of the ciliary reversal-coupled voltage-gated Ca2+ channels Ca2+-dependently.

In Paramecium, ciliary reversal is coupled with voltage-gated Ca(2+) channels on the ciliary membrane. We previously isolated a P. caudatum mutant, cnrC, with a malfunction of the Ca(2+) channels and discovered that the channel activity of cnrC was restored by transfection of the P. caudatum centrin (Pccentrin1p) gene, which encodes a member of the Ca(2+)-binding EF-hand protein family. In this...

متن کامل

Cloning, localization, and axonemal function of Tetrahymena centrin.

Centrin, an EF hand Ca(2+) binding protein, has been cloned in Tetrahymena thermophila. It is a 167 amino acid protein of 19.4 kDa with a unique N-terminal region, coded by a single gene containing an 85-base pair intron. It has > 80% homology to other centrins and high homology to Tetrahymena EF hand proteins calmodulin, TCBP23, and TCBP25. Specific cellular localizations of the closely relate...

متن کامل

Functional dependence of Ca(2+)-activated K+ current on L- and N-type Ca2+ channels: differences between chicken sympathetic and parasympathetic neurons suggest different regulatory mechanisms.

The influx of Ca2+ ions controls many important processes in excitable cells, including the regulation of the gating of Ca(2+)-activated K+ channels (the current IK[Ca]). Various IK[Ca] channels contribute to the regulation of the action-potential waveform, the repetitive discharge of spikes, and the secretion of neurotransmitters. It is thought that large-conductance IK[Ca] channels must be cl...

متن کامل

Visualization of calcium transients controlling orientation of ciliary beat

To image changes in intraciliary Ca controlling ciliary motility, we microinjected Ca Green dextran, a visible wavelength fluorescent Ca indicator, into eggs or two cell stages of the ctenophore Mnemiopsis leidyi. The embryos developed normally into free-swimming, approximately 0.5 mm cydippid larvae with cells and ciliary comb plates (approximately 100 microns long) loaded with the dye. Comb p...

متن کامل

G-proteins modulate cumulative inactivation of N-type (Cav2.2) calcium channels.

Precise regulation of N-type (Ca(V)2.2) voltage-gated calcium channels (Ca-channels) controls many cellular functions including neurotransmitter and hormone release. One important mechanism that inhibits Ca2+ entry involves binding of G-protein betagamma subunits (Gbetagamma) to the Ca-channels. This shifts the Ca-channels from "willing" to "reluctant" gating states and slows activation. Voltag...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2007