Active Creb3L1 can upregulate secretory pathway genes in HeLa cells

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: Creb3L1 is the closest related human orthologue of Drosophila CrebA. CrebA is required to upregulate genes encoding the protein machinery and cargo in specialized secretory cells. To determine if the human orthologues of CrebA, Creb3L1 and Creb3L2, perform the same function, we expressed the truncated active form of Creb3L1 in non-secretory HeLa cells. We then performed microarray experiments and found that active Creb3L1 is sufficient to upregulate genes encoding the protein machinery of the secretory pathway, as observed with Drosophila CrebA. HeLa cells were transiently co-transfected with truncated Creb3L1 (Creb3L1 T) and GFP. Following 20 hours in culture, GFP positive cells were isolated by FACS and RNA was extracted using the Rneasy kit (Qiagen). As a control, mock transfected cells were also subjected to cell sorting and RNA was extracted using the same protocols. At least three replicates were obtained for each group.

ORGANISM(S): Homo sapiens

SUBMITTER: Deborah Andrew 

PROVIDER: E-GEOD-23334 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress