Multimodal factor evaluation system for organismal transparency by hyperspectral imaging

Area of Science:

• * Biophysics and Live Imaging
• * Developmental Biology and Organismal Physiology

Background:

• * Organismal transparency is crucial for whole-body live imaging but its foundations are poorly understood.
• * Multimodal factors (environmental and physiological) influence transparency, yet a comprehensive quantitative evaluation system is lacking.

Purpose of the Study:

• * To develop and validate a quantitative evaluation system for organismal transparency across a broad spectral range (380-1000 nm).
• * To assess the impact of environmental variables and drug treatments on the bio-transparency of the ascidian Ascidiella aspersa.

Main Methods:

• * Utilized hyperspectral microscopy to measure transmittance across a wide spectrum.
• * Quantified bio-transparency as the mean transmittance ratio in the visible light range (400-760 nm).
• * Applied Principal Component Analysis (PCA) to analyze transmittance data and factor groupings.

Main Results:

• * Bio-transparency positively correlated with temperature and inversely with salinity.
• * Reduced pH and six drug treatments significantly decreased bio-transparency (4.2%–58.6%).
• * PCA revealed distinct groupings of factors, suggesting diverse opacification pathways across spectral regions.

Conclusions:

• * The developed system provides a quantitative framework for assessing biological transparency changes.
• * Findings highlight the sensitivity of bio-transparency to environmental and physiological modulations.
• * The analytical framework aids in understanding the mechanisms of biological transparency across various organisms and scales.