Calcium levels inside human cells play a crucial role in normal functioning of cells and even in cell death. The mechanism and factors determining calcium movement across cell membrane has remained elusive to researchers for a long time. Now a group of Indian researchers have reported that a membrane protein in the inside part of human cell is critical in maintaining calcium equilibrium in cells.
The membrane-bound protein is named LRRC8B and it is found inside a cell’s subunit called endoplasmic reticulum (ER).
“ER serves as a reservoir of calcium ions dictating multiple cellular functions. We have found that the protein LRRC8B acts as a calcium leak channel in the ER, thereby causing perturbations in calcium flux across the cell,” explained Dr Amal Kanti Bera, a senior researcher involved in the study. The work has been published in Journal of Cell Science.
The researchers have built upon recent discovery of ER-targeted calcium-sensitive fluorescent protein (CEPIA) constructs reported in 2014. This enabled them to record calcium changes in ER more effectively, explained Arijita Ghosh, another member of the research team. The study was conducted on cultured human cells under laboratory conditions.
Alteration in calcium movement across the cell membrane is has been shown to be liked with several diseases like diabetes, Parkinson’s and Alzheimer’s. Dr. Bera hopes the newfound role of LRRC8B in maintaining cellular calcium levels would open up avenues to probe these diseases which are linked to calcium level dysfunction.
The research team from Indian Institute of Technology Madras and CSIR-Centre for Cellular and Molecular Biology, Hyderabad, included Arijita Ghosh, Nitin Khandelwal, Arvind Kumar and Amal Kanti Bera. The research was supported by the Board of Research in Nuclear Science (BRNS).
India Science Wire