Ca2+-Binding Motif of {beta}{gamma}-Crystallins [Molecular Biophysics]

February 24th, 2014 by Srivastava, S. S., Mishra, A., Krishnan, B., Sharma, Y.

βγ-Crystallin-type double clamp N/D-N/D-X-X-S/T-S motif is an established but sparsely investigated motif for Ca2+-binding. A βγ-crystallin domain is formed of two Greek key motifs, accommodating two Ca2+-binding sites. βγ-Crystallins make a separate class of Ca2+-binding proteins (CaBP), apparently a major group of CaBP in bacteria. Paralleling the diversity in βγ-crystallin domains, these motifs too show great diversity, both in structure and function. Though the expression of some of them has been associated with stress, virulency and adhesion, the functional implications of Ca2+-binding to βγ-crystallins in mediating biological processes are yet to be elucidated.