it is well known that glycoconjugate components of the cell surface and extracellular matrix, play an essential role(s) in many developmental phenomena such as cell differentiation, migration, and cellular interactions. the purpose of this study was to investigate distribution of this macromolecules during differentiation of the notochord and paraxial mesoderm. formalin fixed paraffin sections ...

Limb, somite, and neural crest mesenchyme from quail embryos were implanted orthotopically and heterotopically into chick hosts to ascertain the relative importance of the local environment on mesenchyme migration. It was found that mesenchyme behavior is strongly influenced by the environment. Normally non-migratory, limb mesenchyme is capable of spreading like sclerotome when placed in the so...

Mouse submaxillary epithelium undergoes branching morphogenesis with increase in the curvature of its surface in vivo. Recombination experiments in vitro of the epithelium and mesenchyme between 13- and 14-day rudiments showed (1) that the 14-day mesenchyme more actively induced the epithelium to branch than the 13-day mesenchyme, (2) that the 14-day mesenchyme could produce clefts on smaller e...

The TGFbeta superfamily plays diverse and essential roles in kidney development. Gdf11 and Bmp4 are essential for outgrowth and positioning of the ureteric bud, the inducer of metanephric mesenchyme. During nephrogenesis, Bmp7 is required for renewal of the mesenchyme progenitor population. Additionally, in vitro studies demonstrate inhibitory effects of BMPs and TGFbetas on collecting duct bra...

SUMMARY The ability of foetal rat salivary epithelium, particularly from the parotid gland, to develop morphogenetically and functionally (amylase activity) in various mesenchymes, and the quantitative effects of altering mesenchymal mass on the development of the parotid epithelium, have been studied in vitro. Both parotid and submandibular epithelial rudiments were able to undergo morphogenes...

We have produced a spectrum of limb defects in developing mouse embryos by exposing the mother to smoke from cigarettes with different nicotine concentrations, ethanol, and a combination of ethanol and cigarette smoke. The critical time of exposure was determined to be during day 10 of gestation (vaginal plug=day 0). This time is prior to the critical events which occur between the apical e...