Membrane Proteins in Trypanosomatids Involved in Ca2+ Homeostasis and Signaling

Srinivasan Ramakrishnan; Roberto Docampo

doi:10.3390/genes9060304

Membrane Proteins in Trypanosomatids Involved in Ca²⁺ Homeostasis and Signaling

Genes (Basel). 2018 Jun 19;9(6):304. doi: 10.3390/genes9060304.

Authors

Srinivasan Ramakrishnan¹, Roberto Docampo^{2

3}

Affiliations

¹ Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA. sri@uga.edu.
² Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA. rdocampo@uga.edu.
³ Department of Cellular Biology and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA. rdocampo@uga.edu.

Abstract

Calcium ion (Ca²⁺) serves as a second messenger for a variety of cell functions in trypanosomes. Several proteins in the plasma membrane, acidocalcisomes, endoplasmic reticulum, and mitochondria are involved in its homeostasis and in cell signaling roles. The plasma membrane has a Ca²⁺ channel for its uptake and a plasma membrane-type Ca²⁺-ATPase (PMCA) for its efflux. A similar PMCA is also located in acidocalcisomes, acidic organelles that are the primary Ca²⁺ store and that possess an inositol 1,4,5-trisphosphate receptor (IP₃R) for Ca²⁺ efflux. Their mitochondria possess a mitochondrial calcium uniporter complex (MCUC) for Ca²⁺ uptake and a Ca²⁺/H⁺ exchanger for Ca²⁺ release. The endoplasmic reticulum has a sarcoplasmic-endoplasmic reticulum-type Ca²⁺-ATPase (SERCA) for Ca²⁺ uptake but no Ca²⁺ release mechanism has been identified. Additionally, the trypanosomatid genomes contain other membrane proteins that could potentially bind calcium and await further characterization.

Keywords: Leishmania; Trypanosoma; acidocalcisome; calcium; mitochondria.

Publication types

Review

Abstract

Publication types

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