| Popis: |
The vertebrate endocrine pancreas has the crucial function of maintaining blood sugar homeostasis. This role is dependent upon the development and maintenance of pancreatic islets comprising appropriate ratios of hormone-producing cells. Pax6 is a well-conserved transcription factor that contains two DNA-binding domains, and plays a key role in the development of eye, brain and pancreas in vertebrates. Within the endocrine progenitor pool, a variety of transcription factors influence cell fate decisions. Here we show that in zebrafish, in absence of pax6b, there is a loss of insulin-producing cells, a decrease of somatostatin-expressing cells, a decrease of glucagon-expressing cells and a strong increase of ghrelin-expressing cells. We propose a model where, in absence of pax6b, cells that should become insulin-positive become ghrelin-expressing cells. In the second part of the work we describe the generation and characterization of zebrafish transgenic lines responsive to CREB signaling. These lines could represent useful tools for studying specific human pathologies |
