Gene expression dynamics of human and mouse craniofacial development at the single-cell level

Area of Science:

• Developmental Biology
• Genetics
• Cell Biology

Background:

• Human craniofacial development involves complex cell-type specification, but detailed understanding remains limited.
• Existing knowledge gaps hinder comprehension of normal development and congenital conditions like orofacial clefts.

Purpose of the Study:

• To create a comprehensive cellular atlas of human craniofacial development.
• To identify cell subtypes, their functions, and their involvement in orofacial clefts.

Main Methods:

• Single-nucleus RNA sequencing (snRNA-seq) of human craniofacial tissues from 4 to 8 post-conception weeks.
• Comparative analysis with mouse developmental stages using snRNA-seq and spatial transcriptomics.
• Identification and characterization of distinct cellular and molecular signatures.

Main Results:

• Detailed catalog of diverse cell subtypes including mesenchyme, epithelium, and cranial neural crest.
• Demonstrated functional conservation between human and mouse craniofacial cell types.
• Identified specific cell subtypes contributing to facial morphology and orofacial cleft risk factors.
• Pinpointed ectodermal and epithelial subtypes affected by genetic variants in orofacial cleft patients.

Conclusions:

• This study provides an unprecedented cellular-level resource for human craniofacial development.
• Findings illuminate the cellular basis of normal facial formation and the etiology of orofacial clefts.
• The data facilitates future research into craniofacial anomalies and therapeutic strategies.