Molecular Cross-Talk between Gravity- and Light-Sensing Mechanisms in Euglena gracilis.

Adeel Nasir,Julia Stoltze,Peter Rolf Richter,Binod Prasad,Viktor Daiker,Michael Lebert,Sebastian Michael Strauch,Aude Le Bail

doi:10.3390/ijms23052776

Abstract

Euglena gracilis is a photosynthetic flagellate. To acquire a suitable position in its surrounding aquatic environment, it exploits light and gravity primarily as environmental cues. Several physiological studies have indicated a fine-tuned relationship between gravity sensing (gravitaxis) and light sensing in E. gracilis. However, the underlying molecular mechanism is largely unknown. The photoreceptor photoactivated adenylyl cyclase (PAC) has been studied for over a decade. Nevertheless, no direct/indirect interaction partner (upstream/downstream) has been reported for PAC. It has been shown that a specific protein, kinase A (PKA), showed to be involved in phototaxis and gravitaxis. The current study reports the localization of the specific PKA and its relationship with PAC.

Highlights

Light and gravity are the most important environmental cues that many living organisms utilize to orient themselves in their surroundings [1–6]
The subcellular localization of PKA in E. gracilis was carried out using a genomic antibody
The anti-PKA antibody was generated using the genomic antibody (GAB) approach [27], which ensures the detection of an antigen in its native and denatured state

Summary

Introduction

Light and gravity are the most important environmental cues that many living organisms utilize to orient themselves in their surroundings [1–6]. Plants present a prominent example, as they perform directional movements in response to light (phototropism) and gravity (gravitropism) to orient themselves to a favorable niche for their development and growth. A growing body of evidence suggests that a synergistic effect of phototropism and gravitropism facilitates plant growth [1]. Free-swimming eukaryotic unicellulars are largely dependent on light and gravity for their growth and survival [4,8]. Dissimilar to plants, there is not much known about the plausible underlying molecular mechanism that controls both light- or gravity-sensing responses in unicellular organisms. This study aims to understand the underlying molecular mechanism of interdependent responses of Euglena gracilis to light and gravity stimuli

Objectives

Methods

Results

Conclusion