NALINI SINGH, KARAN SINGH RAJPUT AND SHWETA SARAN
School of Life Sciences, Jawaharlal Nehru University, New Delhi-110 067, India
*(e-mail : ssaran@mail.jnu.ac.in; Mobile : 011-26704157)
(Received : May 12, 2019; Accepted : July 18, 2019)
ABSTRACT
Calpains are ubiquitously present Ca2+-dependent cysteine proteases. They are involved in many important cellular processes like autophagy, apoptosis, cell proliferation, cell migration, etc. In this study, we have shown the expression pattern of cplA mRNA and effect of cplA overexpression in growth and development of Dictyostelium discoideum. Maximum mRNA expression level was observed in the mounds though vegetative and fruiting bodies also showed high levels of expression. Overexpression of DdcplA reduced cell proliferation and showed defects in development. Development was asynchronous forming stalky fruiting bodies when compared to wild type Ax2 cells. Stalky fruiting body showed that large number of cells participated in stalk cell differentiation that undergo autophagic cell death suggesting that calpain may have a role to play in autophagy. mRNA levels of autophagic genes were also elevated in cplA overexpressing cells showing its possible involvement in autophagy. There are number of studies indicating that calpain can both induce and inhibit autophagy. Our study suggests that overexpression of calpain upregulates autophagy in D. discoideum.
Key words :Calpain, D. discoideum, autophagy