Title
A temperature-responsive gene in sorghum encodes a glycine-rich protein that interacts with calmodulin
Author
Supreet Singh, Amardeep Singh Virdi, Rajdeep Jaswal, Mrinalini Chawla, Sanjay Kapoor, Samar B. Mohapatra, Narayanan Manoj, Ashwani Pareek, Sanjay Kumar, Prabhjeet Singh
Year
2017
Journal
Biochimie
Abstract
Imposition of different biotic and abiotic stress conditions results in an increase in intracellular levels of Ca2+ which is sensed by various sensor proteins. Calmodulin (CaM) is one of the best studied transducers of Ca2+ signals. CaM undergoes conformational changes upon binding to Ca2+ and interacts with different types of proteins, thereby, regulating their activities. The present study reports the cloning and characterization of a sorghum cDNA encoding a protein (SbGRBP) that shows homology to glycine-rich RNA-binding proteins. The expression of SbGRBP in the sorghum seedlings is modulated by heat stress. The SbGRBP protein is localized in the nucleus as well as in cytosol, and shows interaction with CaM that requires the presence of Ca2+. SbGRBP depicts binding to single and also double stranded DNA. Fluorescence spectroscopic analyses suggest that interaction of SbGRBP with nucleic acids may be modulated after binding with CaM. To our knowledge, this is the first study to provide evidence for interaction of a stress regulated glycine-rich RNA-binding protein with CaM.
Instrument
J-815
Keywords
Circular dichroism, Secondary structure, Ligand binding, Biochemistry