Notch inhibits Ptf1 function and acinar cell differentiation in developing mouse and zebrafish pancreas.

Notch signaling regulates cell fate decisions in a variety of adult and embryonic tissues, and represents a characteristic feature of exocrine pancreatic cancer. In developing mouse pancreas, targeted inactivation of Notch pathway components has defined a role for Notch in regulating early endocrine differentiation, but has been less informative with respect to a possible role for Notch in regulating subsequent exocrine differentiation events. Here, we show that activated Notch and Notch target genes actively repress completion of an acinar cell differentiation program in developing mouse and zebrafish pancreas.

Fold recognition, homology modeling, docking simulations, kinetics analysis and mutagenesis of ATP/CTP:tRNA nucleotidyltransferase from Methanococcus jannaschii.

ATP/CTP:tRNA nucleotidyltransferases (NTases) and poly(A) polymerases (PAPs) belong to the same superfamily and their catalytic domains are remotely related. Based on the results of fold-recognition analysis and comparison of secondary structure patterns, we predicted that these two NTase families share three domains, corresponding to "palm," "fingers," and "fingernails" in the PAP crystal structure. A homology model of tRNA NTase from Methanococcus jannaschii was constructed.