Compartment‐specific Ca2+ imaging in the green alga Chlamydomonas reinhardtii reveals high light‐induced chloroplast Ca2+ signatures
Articolo
Data di Pubblicazione:
2023
Citazione:
Compartment‐specific Ca2+ imaging in the green alga Chlamydomonas reinhardtii reveals high light‐induced chloroplast Ca2+ signatures / M. Pivato, M. Grenzi, A. Costa, M. Ballottari. - In: NEW PHYTOLOGIST. - ISSN 0028-646X. - (2023), pp. 1-14. [Epub ahead of print] [10.1111/nph.19142]
Abstract:
To investigate the role of intracellular Ca2+ signaling in the perception and response mechanisms to light in unicellular microalgae, the genetically encoded ratiometric Ca2+ indicator Yellow Cameleon (YC3.6) was expressed in the model organism for green algae Chlamydomonas reinhardtii, targeted to cytosol, chloroplast, and mitochondria. Through in vivo single-cell confocal microscopy imaging, light-induced Ca2+ signaling was investigated in different conditions and different genotypes, including the photoreceptors mutants phot and acry. A genetically encoded H2 O2 sensor was also adopted to investigate the possible role of H2 O2 formation in light-dependent Ca2+ signaling. Light-dependent Ca2+ response was observed in Chlamydomonas reinhardtii cells only in the chloroplast as an organelle-autonomous response, influenced by light intensity and photosynthetic electron transport. The absence of blue and red-light photoreceptor aCRY strongly reduced the light-dependent chloroplast Ca2+ response, while the absence of the blue photoreceptor PHOT had no significant effects. A correlation between high light-induced chloroplast H2 O2 gradients and Ca2+ transients was drawn, supported by H2 O2 -induced chloroplast Ca2+ transients in the dark. In conclusion, different triggers are involved in the light-induced chloroplast Ca2+ signaling as saturation of the photosynthetic electron transport, H2 O2 formation, and aCRY-dependent light perception.
Tipologia IRIS:
01 - Articolo su periodico
Keywords:
Chlamydomonas; calcium; cell signaling; chloroplast; photoreceptor; photosynthesis; reactive oxygen species; single-cell imaging
Elenco autori:
M. Pivato, M. Grenzi, A. Costa, M. Ballottari
Link alla scheda completa: