In vivo light-sheet microscopy resolves localisation patterns of FSD1, a superoxide dismutase with function in root...

Area of Science:

• Plant Biology
• Molecular Biology
• Biochemistry

Background:

• Superoxide dismutases (SODs) detoxify superoxide radicals, crucial for cellular function.
• Temporal and spatial expression patterns of SODs are linked to their specific roles.
• Understanding iron superoxide dismutase 1 (FSD1) localization and function is key to plant stress responses.

Purpose of the Study:

• To investigate the in vivo developmental expression and subcellular localization of FSD1 in Arabidopsis.
• To elucidate the functional roles of FSD1 in plant development and stress tolerance.

Main Methods:

• Utilized light-sheet and Airyscan confocal microscopy to visualize FSD1-GFP localization.
• Generated and analyzed fsd1 knockout mutants to assess phenotypic consequences.
• Performed genetic complementation to validate mutant phenotypes.

Main Results:

• FSD1-GFP accumulated during seed germination and in specific root cell types (lateral root cap, columella, endodermis/cortex initials).
• Major FSD1-GFP pools were found in plastid stroma, nucleus, and cytosol, with nuclear FSD1-GFP being largely immobile.
• fsd1 mutants showed reduced lateral root numbers and impaired seed germination under salt stress, phenotypes rescued by complementation.

Conclusions:

• FSD1 plays significant roles in Arabidopsis seed germination, lateral root development, and salt stress tolerance.
• Plastidic FSD1 is likely essential for oxidative stress tolerance.
• This study reveals novel developmental and osmoprotective functions for SODs in plants.