A quantitative method for staging mouse embryos based on limb morphometry

Area of Science:

• Developmental Biology
• Morphometrics
• Bioinformatics

Background:

• Accurate staging of embryonic development is crucial for understanding morphogenesis.
• Traditional methods for staging mouse embryos can be time-consuming and subjective.
• Limb bud development exhibits distinct morphological changes throughout embryogenesis.

Purpose of the Study:

• To develop a quantitative method for determining embryonic mouse developmental stages.
• To create a standardized ontogenetic trajectory for mouse limb bud development.
• To introduce a freely available online tool for staging mouse embryos.

Main Methods:

• Application of geometric morphometrics to analyze shape changes in mouse limb buds from embryonic day 10 to 15.
• Creation of a standard ontogenetic trajectory representing limb bud shape evolution.
• Development of the embryonic mouse ontogenetic staging system (eMOSS) based on limb bud morphology.

Main Results:

• A quantitative characterization of limb bud shape change during morphogenesis was established.
• The developed trajectory allows inference of developmental stage from limb bud shape with a typical uncertainty of 2 hours.
• The eMOSS tool was created as a fast, reliable, and accessible online resource for embryo staging.

Conclusions:

• The eMOSS system provides a precise and efficient method for staging embryonic mice.
• This tool facilitates the phenotyping of early limb abnormalities.
• The quantitative approach advances the understanding of limb bud morphogenesis and developmental timing.