Kwong, E.M.L., Ho, J.C.H., Lau, M.C.C., You, M.S., Jiang, Y.J., Tse, W.K.F. (2017) Restoration of polr1c in early embryogenesis rescues the Type 3 Treacher Collins Syndrome facial malformation phenotype in zebrafish. The American journal of pathology. 188(2):336-342.
Treacher Collins Syndrome (TCS) is a rare congenital birth disorder (1 in 50,000 live births) characterized by severe craniofacial defects. Recently, our group unfolded the pathogenesis of polr1c Type 3 TCS by using the zebrafish model. Facial development depends on the neural crest cells, in which polr1c plays a role in regulating its expression. In this report, we aim to identify the functional time window of polr1c in TCS by the use of photo-morpholino to restore the polr1c expression at different time points. Results suggested that the restoration of polr1c at 8 hours post fertilization could rescue the TCS facial malformation phenotype by correcting the neural crest cell expression, reducing the cell death, and normalizing the p53 mRNA expression level in the rescued morphants. However, such recovery could not be reproduced if the polr1c is restored after 30 hours post fertilization.