Calcium Signaling Commands Phagosome Maturation Process

Abstract

Phagosome–lysosome (P–L) fusion is one of the central immune-effector responses of host. It is known that phagosome maturation process is associated with numerous signaling cascades and among these, important role of calcium (Ca²⁺) signaling has been realized recently. Ca²⁺ plays key roles in actin rearrangement, activation of NADPH oxidase and protein kinase C (PKC). Involvement of Ca²⁺ in these cellular processes directs phagosomal maturation process. Some of the intracellular pathogens have acquired the strategies to modulate Ca²⁺ associated pathways to block P–L fusion process. In this review we have described the mechanism of Ca²⁺ signals that influence P–L fusion by controlling ROS, actin and PKC signaling cascades. We have also discussed the strategies implemented by the intracellular pathogens to manipulate Ca²⁺ signaling to consequently subvert P–L fusion. A detail study of factors associated in manipulating Ca²⁺ signaling may provide new insights for the development of therapeutic tools for more effective treatment options against infectious diseases.

Keywords:

• Calcium signaling
• phogosomal maturation
• reactive oxygen species
• actin kinetics and PKC signaling
• intracellular pathogens

Additional information

Funding

G.P. was supported by a fellowship from Indian Council of Medical Research (ICMR), Govt. of India. P.R.A was supported by the Research Associateship from the Indian Council of Medical Research, Govt. of India (80/796/2013-ECD). R.S. was supported by a fellowship from Council of Scientific and Industrial Research, Govt. of India. The laboratory of S.M. is supported by the grants from Department of Biotechnology (DBT), Govt. of India (BT/PR20669/MED/29/1072/2016; BT/PR12817/COE/34/23/2015 and Tata Innovation Fellowship (BT/HRD/35/01/03/2018), Department of Science and Technology (DST), Govt. of India (EMR/2016/000644) and core grant from CDFD by DBT.