Making maxillary barbels with a proximal-distal gradient of Wnt signals in matrix-bound mesenchymal cells.

ABSTRACT: The evolution of specific appendages is made possible by the ontogenetic deployment of general cell signaling pathways. Many fishes, amphibians and reptiles have unique skin appendages known as barbels, which are poorly understood at the cellular and molecular level. In this study, we examine the cell arrangements, cell division patterns, and gene expression profiles associated with the zebrafish maxillary barbel, or ZMB. The earliest cellular organization of the ZMB is an internal whorl of mesenchymal cells in the dermis of the maxilla; there is no epithelial placode, nor any axially-elongated epithelial cells as expected of an apical ectodermal ridge (AER). As the ZMB develops, cells in S-phase are at first distributed randomly throughout the appendage, gradually transitioning to a proli

SUBMITTER: Figueroa F 

PROVIDER: S-EPMC4620582 | biostudies-literature | 2015 Nov-Dec

REPOSITORIES: biostudies-literature