Sacral development in mice
Location
Philadelphia, PA
Start Date
17-4-2026 1:30 PM
End Date
17-4-2026 2:30 PM
Description
Background and Rationale
Shifts in sacral count and identity have occurred multiple times across mammalian evolution, facilitating different locomotor patterns. Understanding sacral development, a component of the spine and pelvis, is crucial for researching human bipedalism as it is facilitated by several changes to the spine and pelvis. Hox genes play a role in specifying vertebral count and identity during development. Hoxd11 specifically acts at the lumbosacral boundary.
Aim
This project aims to establish several time points across early mouse development at which to assess Hoxd11 expression in the sacrum and pelvis.
Methods
Modified Periodic Acid-Schiff (PAS) staining was used to visualize the ossification and development of the lumbar and sacral spine in FVB mice between postnatal day (p) 0-13. Age points were selected based on known key points of limb development and cleared full-body samples of mice. Prior to staining, samples were dissected below the ribcage, processed in 10% EDTA, and embedded in paraffin wax. Histological sections between 7-9 microns thick were taken on an automatic microtome. After Modified PAS staining, slides were visualized at 80X on a Motic Slide Scanner.
Results
Age points were chosen to represent several developmental stages of early vertebral formation. Based on the state of growth plate formation and organization in the first and third sacral vertebrae, time points of p0, p5, p9, and p13 were selected for future projects.
Significance
This project was conducted in order to determine developmentally relevant time points for vertebrae in the sacrum. It will be used as the foundation for future experimental studies.
Embargo Period
5-20-2026
Sacral development in mice
Philadelphia, PA
Background and Rationale
Shifts in sacral count and identity have occurred multiple times across mammalian evolution, facilitating different locomotor patterns. Understanding sacral development, a component of the spine and pelvis, is crucial for researching human bipedalism as it is facilitated by several changes to the spine and pelvis. Hox genes play a role in specifying vertebral count and identity during development. Hoxd11 specifically acts at the lumbosacral boundary.
Aim
This project aims to establish several time points across early mouse development at which to assess Hoxd11 expression in the sacrum and pelvis.
Methods
Modified Periodic Acid-Schiff (PAS) staining was used to visualize the ossification and development of the lumbar and sacral spine in FVB mice between postnatal day (p) 0-13. Age points were selected based on known key points of limb development and cleared full-body samples of mice. Prior to staining, samples were dissected below the ribcage, processed in 10% EDTA, and embedded in paraffin wax. Histological sections between 7-9 microns thick were taken on an automatic microtome. After Modified PAS staining, slides were visualized at 80X on a Motic Slide Scanner.
Results
Age points were chosen to represent several developmental stages of early vertebral formation. Based on the state of growth plate formation and organization in the first and third sacral vertebrae, time points of p0, p5, p9, and p13 were selected for future projects.
Significance
This project was conducted in order to determine developmentally relevant time points for vertebrae in the sacrum. It will be used as the foundation for future experimental studies.