Project description:Terminal differentiation in parotid acini relies on sustained changes in gene expression during the first few postnatal weeks. Little is known about what drives these changes. Expression measurements along with knowledgebased network analysis was used to develop a prospective gene regulatory network that drives differentiation. We used both microRNA and mRNA expression measurements along with knowledgebased network analysis was used to develop a prospective gene regulatory network that drives differentiation. laser capture microdissection was used to isolate acinar cells from the parotid at four timepoints in triplicate (E20, P5, P15, and P25). RNA was isolated, and used to measure microRNA expression.
Project description:Terminal differentiation in parotid acini relies on sustained changes in gene expression during the first few postnatal weeks. Little is known about what drives these changes. Expression measurements along with knowledgebased network analysis was used to develop a prospective gene regulatory network that drives differentiation. We used expression measurements along with knowledgebased network analysis was used to develop a prospective gene regulatory network that drives differentiation. laser capture microdissection was used to isolate acinar cells from the parotid at nine timepoints in triplicate (E18, E20, P0, P2, P5, P9, P15, P20, and P25). RNA was isolated, and applied to the affymetrix rat genome array 230.
Project description:Terminal differentiation in parotid acini relies on sustained changes in gene expression during the first few postnatal weeks. Little is known about what drives these changes. Expression measurements along with knowledgebased network analysis was used to develop a prospective gene regulatory network that drives differentiation. We used both microRNA and mRNA expression measurements along with knowledgebased network analysis was used to develop a prospective gene regulatory network that drives differentiation.
Project description:Although mesenchyme is essential for inducing the epithelium of ectodermal organs, its precise role in organ-specific epithelial fate determination remains poorly understood. To elucidate roles of tissue interactions in cellular differentiation, we performed single cell RNA sequencing and imaging analyses of recombined tissues in which embryonic mouse salivary gland mesenchyme and epithelium were switched ex vivo. We found partial induction of molecules that define gland-specific acinar and myoepithelial cells in recombined salivary epithelium. Parotid epithelium (serous gland) recombined with submandibular mesenchyme (mixed serous-mucous, but predominantly mucous gland) began to express mucous acinar genes not intrinsic to the parotid gland. While myoepithelial cells do not normally line parotid acini, newly induced myoepithelial cells densely populated recombined parotid acini. However, mucous acinar and myoepithelial markers continued to be expressed in submandibular epithelial cells recombined with parotid mesenchyme. Consequently, some epithelial cells appeared to be plastic, such that their fate could still be altered in response to mesenchymal signaling, whereas other epithelial cells appeared to be already committed to a specific fate. We also discovered evidence for bidirectional induction: transcriptional changes were observed not only in the epithelium but also in the mesenchyme after heterotypic tissue recombination. For example, parotid epithelium induced the expression of muscle-related genes in submandibular fibroblasts that began to mimic parotid fibroblast gene expression. These studies provide the first comprehensive unbiased molecular characterization of tissue recombination approaches exploring the regulation of cell fate.
Project description:Although mesenchyme is essential for inducing the epithelium of ectodermal organs, its precise role in organ-specific epithelial fate determination remains poorly understood. To elucidate roles of tissue interactions in cellular differentiation, we performed single cell RNA sequencing and imaging analyses of recombined tissues in which embryonic mouse salivary gland mesenchyme and epithelium were switched ex vivo. We found partial induction of molecules that define gland-specific acinar and myoepithelial cells in recombined salivary epithelium. Parotid epithelium (serous gland) recombined with submandibular mesenchyme (mixed serous-mucous, but predominantly mucous gland) began to express mucous acinar genes not intrinsic to the parotid gland. While myoepithelial cells do not normally line parotid acini, newly induced myoepithelial cells densely populated recombined parotid acini. However, mucous acinar and myoepithelial markers continued to be expressed in submandibular epithelial cells recombined with parotid mesenchyme. Consequently, some epithelial cells appeared to be plastic, such that their fate could still be altered in response to mesenchymal signaling, whereas other epithelial cells appeared to be already committed to a specific fate. We also discovered evidence for bidirectional induction: transcriptional changes were observed not only in the epithelium but also in the mesenchyme after heterotypic tissue recombination. For example, parotid epithelium induced the expression of muscle-related genes in submandibular fibroblasts that began to mimic parotid fibroblast gene expression. These studies provide the first comprehensive unbiased molecular characterization of tissue recombination approaches exploring the regulation of cell fate.