CrebA is a major and direct regulator of secretory pathway gene expression

ABSTRACT: Abstract: Secretion occurs in all cells, with relatively low levels in most cells and extremely high levels in specialized secretory cells, such as those of the pancreas, salivary and mammary glands. Here, we report that the CrebA/Creb3-like family of bZip transcription factors functions to upregulate expression of both the general protein machinery required in all cells for secretion and of cell-type specific secreted proteins. Drosophila CrebA directly binds the enhancers of secretory pathway genes and is both necessary and sufficient to activate expression of every secretory pathway component gene examined thus far. Microarray profiling reveals that CrebA also upregulates expression of genes encoding cell type specific secreted components. Finally, we find that the human CrebA orthologues, Creb3L1 and Creb3L2, have the ability to upregulate the secretory pathway in non-secretory cell types. Goals: The goals of the microarray experiments were to identify additional targets of the CrebA transcription factor to learn the range of genes regulated by this transcription factor during embryogenesis. Previous work had indicated that CrebA upregulates the protein machinery of the early secretory pathway. Our new data now shows that in addition to the protein machinery, CrebA also upregulates genes encoding the protein cargo that is secreted from specialized secretory organs. RNA was isolated from stage 11-15 wild type Drosophila embryos and compared to RNA from CrebA null mutant embryos of the same age; all samples were hybridized to the Drosophila Genome 2.0 Affymetrix array. Three individual replicates were obtained for each sample.

ORGANISM(S): Drosophila melanogaster

SUBMITTER: Deborah Andrew 

PROVIDER: E-GEOD-23346 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress