The DOI matches its Crossref record; 33 of the 33 references it cites were found in a registry or an index.
Functional stoichiometry of the unitary calcium-release-activated calcium channel
Open accessAbstract
Two proteins, STIM1 in the endoplasmic reticulum and Orai1 in the plasma membrane, are required for the activation of Ca 2+ release-activated Ca 2+ (CRAC) channels at the cell surface. How these proteins interact to assemble functional CRAC channels has remained uncertain. Here, we determine how many Orai1 and STIM1 molecules are required to form a functional CRAC channel. We engineered several genetically expressed fluorescent Orai1 tandem multimers and a fluorescent, constitutively active STIM1 mutant. The tandem multimers assembled into CRAC channels, as seen by rectifying inward currents and by cytoplasmic calcium elevations. CRAC channels were visualized as fluorescent puncta in total internal reflection microscopy. With single-molecule imaging techniques, it was possible to observe photo-bleaching of individual fluorophores and to count the steps of bleaching as a measure of the stoichiometry of each CRAC channel complex. We conclude that the subunit stoichiometry in an active CRAC channel is four Orai1 molecules and two STIM1 molecules. Fluorescence resonance energy transfer experiments also showed that four Orai1 subunits form the assembled channel. From the fluorescence intensity of single fluorophores, we could estimate that our transfected HEK293 cells had almost 400,000 CRAC channels and that, when intracellular Ca 2+ stores were depleted, the channels clustered in aggregates containing ≈1,300 channels, amplifying the local Ca 2+ entry.
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Cites
A mutation in Orai1 causes immune deficiency by abrogating CRAC channel function
Feske, S., Gwack, Y., Prakriya, M., Srikanth, S., Puppel, S.-H., Tanasa, B., Hogan, P. G., Lewis, R. S., Daly, M., & Rao, A. (2006) · Nature · doi:10.1038/nature04702 · Cited by 2,288
STIM Is a Ca2+ Sensor Essential for Ca2+-Store-Depletion-Triggered Ca2+ Influx
Liou, J., Kim, M. L., Do Heo, W., Jones, J. T., Myers, J. W., Ferrell, J. E., & Meyer, T. (2005) · Current Biology · doi:10.1016/j.cub.2005.05.055 · Cited by 2,136
STIM1, an essential and conserved component of store-operated Ca2 + channel function
Roos, J., DiGregorio, P. J., Yeromin, A. V., Ohlsen, K., Lioudyno, M., Zhang, S., Safrina, O., Kozak, J. A., Wagner, S. L., Cahalan, M. D., et al. (2005) · The Journal of Cell Biology · doi:10.1083/jcb.200502019 · Cited by 1,828
Depletion of intracellular calcium stores activates a calcium current in mast cells
Hoth, M., & Penner, R. (1992) · Nature · doi:10.1038/355353a0 · Cited by 1,751
CRACM1 Is a Plasma Membrane Protein Essential for Store-Operated Ca 2+ Entry
Vig, M., Peinelt, C., Beck, A., Koomoa, D. L., Rabah, D., Koblan-Huberson, M., Kraft, S., Turner, H., Fleig, A., Penner, R., et al. (2006) · Science · doi:10.1126/science.1127883 · Cited by 1,321
Subunit stoichiometry of a mammalian K+ channel determined by construction of multimeric cDNAs
Liman, E. R., Tytgat, J., & Hess, P. (1992) · Neuron · doi:10.1016/0896-6273(92)90239-a · Cited by 1,084
Zhang, S. L., Yeromin, A. V., Zhang, X. H.-F., Yu, Y., Safrina, O., Penna, A., Roos, J., Stauderman, K. A., & Cahalan, M. D. (2006) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.0603161103 · Cited by 866
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Subunit counting in membrane-bound proteins
Ulbrich, M. H., & Isacoff, E. Y. (2007) · Nature Methods · doi:10.1038/nmeth1024 · Cited by 690
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Cited by
Store-Operated Calcium Channels
Prakriya, M., & Lewis, R. S. (2015) · Physiological Reviews · doi:10.1152/physrev.00020.2014 · Cited by 1,239
Molecular Basis of Calcium Signaling in Lymphocytes: STIM and ORAI
Hogan, P. G., Lewis, R. S., & Rao, A. (2010) · Annual Review of Immunology · doi:10.1146/annurev.immunol.021908.132550 · Cited by 760
The functional network of ion channels in T lymphocytes
Cahalan, M. D., & Chandy, K. G. (2009) · Immunological Reviews · doi:10.1111/j.1600-065x.2009.00816.x · Cited by 599
Diseases caused by mutations in ORAI1 and STIM1
Lacruz, R. S., & Feske, S. (2015) · Annals of the New York Academy of Sciences · doi:10.1111/nyas.12938 · Cited by 443
Store-operated CRAC channels: function in health and disease
Parekh, A. B. (2010) · Nature Reviews Drug Discovery · doi:10.1038/nrd3136 · Cited by 317
Metadata
- Authors
- Ji, W., Xu, P., Li, Z., Lu, J., Liu, L., Zhan, Y., Chen, Y., Hille, B., Xu, T., & Chen, L.
- Venue
- Proceedings of the National Academy of Sciences
- Published
- 2008-09-09
- Volume
- 105
- Issue
- 36
- Pages
- 13668-13673
- ISSN
- 0027-8424 (ISSN-L)
- 1091-6490
- OpenAlex
- W2009707152
- Cited by
- 254
- References
- 33
- FWCI
- 13.22
- Type
- journal article
- Language
- en
- Open access
- green
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