Epithelial-mesenchymal transition occurs after epidermal development in mouse skin.
In the present study, we studied epithelial-mesenchymal transition (EMT) with fetal and postnatal serial skin sections. E-cadherin, occludin and zonula occludens 1 (ZO-1)-expressing cells appear in the dermal area from E18.5 to postnatal day 9 (P9), with highest expression from P2 to P5. The co-expression of mesenchymal marker alpha-smooth muscle (alpha-SMA), fibronectin and vimentin with E-cadherin in these dermal cells was further examined. Almost no dermal cells express alpha-SMA before P0. From P2 to P6, cells expressing both E-cadherin and alpha-SMA appear in the dermis. In contrast, fibronectin-releasing cells were detected in the dermis as early as on E15.5, although on P5, some dermal cells was found weakly expressing both fibronectin and E-cadherin, most cells strongly expressing fibronectin did not express E-cadherin. Vimentin was mainly expressed in both endothelial and blood-derived cells and did not show co-expression with E-cadherin. Confocal microscopy studies further found that during EMT, E-cadherin appears intracellularly, while the expression of alpha-SMA starts from the membrane area and moves to the cytosol of the cells. Our data are the first in vivo evidence that EMT occurs during mouse skin development. Dermal cells are derived from EMT and other origins, including blood, during skin development.
Kong
Wuyi
W
Children's Surgical Research Laboratory, Stanford University School of Medicine, 257 Campus Drive, Stanford, CA 94305-5148, USA. wkong@stanford.edu <wkong@stanford.edu>
Li
Shaowei
S
Liu
Cheng
C
Bari
Ali Sina
AS
Longaker
Michael T
MT
Lorenz
H Peter
HP
D000199:Actins / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D015415:Biomarkers / Q000378:metabolism; D015820:Cadherins / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000378:metabolism; D004817:Epidermis / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D004848:Epithelium / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D005260:Female; D005353:Fibronectins / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D008648:Mesoderm / Q000166:cytology / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D010750:Phosphoproteins / Q000378:metabolism; D011247:Pregnancy; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins; D012867:Skin / Q000196:embryology* / Q000254:growth & development* / Q000378:metabolism; D014746:Vimentin / Q000378:metabolism; D062826:Zonula Occludens-1 Protein
D000199:Actins; D015415:Biomarkers; D015820:Cadherins; D002135:Calcium-Binding Proteins; D005353:Fibronectins; D008565:Membrane Proteins; D010750:Phosphoproteins; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins; C470944:S100a4 protein, mouse; C569043:Tjp1 protein, mouse; D014746:Vimentin; D062826:Zonula Occludens-1 Protein