The Expression Of NBC1 In The Development Of Rat Pancreas

We expected to use high-density microarray(Affymetrix)to analyze the expression profiles of pancreas development.We generated transcriptional profiles of pancreatic tissue isolated from five biologically significant stages of development:embryonic day(E)12.5,E15.5,E18.5, newborn and adult pancreas.These analyses implicate that many genes related to pancreatic function are enriched in the later gestation when islet architecture and function are gradually forming.The differential expression of NBC1 mRNA was verified by RT-PCR.Moreover,the differential expression of NBC1 protein was identified by western blotting.NBC1 localized both in islets and exocrine pancreas,which was detected by double-labeling immunofluorescence.Combined with RT-PCR and Western blot analysis,we found that the first peak of NBC1 expression occurred at embryonic day 18.5(E18.5) and the second peak at postnatal day 14(P14).In contrast,lowest NBC1 expression occurred at P7 and adult stage.Our results demonstrated the presence of NBC1 in the plasma membrane ofβandαcells as well as in the basolateral membrane of acinar cells in rat developing pancreas. Furthermore,we still found that the positive signals were strong in the plasma membrane ofβcells in the adult rat pancreas but became weak in the basolateral membrane of acinar cells.The data highly suggests that the NBC1 variants are diversely expressed in pancreas in different developmental stage,where they may display their functions in pancreatic development through HCO3~- transport and pH regulation.