TY - JOUR
T1 - Endodermal expression of Nkx6 genes depends differentially on Pdx1
AU - Pedersen, Jesper K
AU - Nelson, Shelley B
AU - Jørgensen, Mette Christine
AU - Henseleit, Korinna D
AU - Fujitani, Yoshio
AU - Wright, Chris V E
AU - Sander, Maike
AU - Serup, Palle
AU - Beta Cell Biology Consortium
PY - 2005/12/15
Y1 - 2005/12/15
N2 - Nkx family members are essential for normal development of many different tissues such as the heart, lungs, thyroid, prostate, and CNS. Here, we describe the endodermal expression pattern of three Nkx6 family genes of which two shows conserved expression in the early pancreatic epithelium. In chicken, Nkx6.1 expression is not restricted to the presumptive pancreatic area but is more broadly expressed in the endoderm. In mice, expression of Nkx6.1 is restricted to the pancreatic epithelium. In both mice and chicken, Nkx6.2 and Pdx1 are expressed in very similar domains, identifying Nkx6.2 as a novel marker of pancreas endoderm. Additionally, our results show that Nkx6.3 is expressed transiently in pancreatic endoderm in chicken but not mouse embryos. At later stages, Nkx6.3 is found in the caudal stomach and rostral duodenum in both species. Finally, we demonstrate that Pdx1 is required for Nkx6.1 but not Nkx6.2 expression in mice and that ectopic Pdx1 can induce Nkx6.1 but not Nkx6.2 or Nkx6.3 expression in anterior chicken endoderm. These results demonstrate that Nkx6.1 lies downstream of Pdx1 in a genetic pathway and that Pdx1 is required and sufficient for Nkx6.1 expression in the early foregut endoderm.
AB - Nkx family members are essential for normal development of many different tissues such as the heart, lungs, thyroid, prostate, and CNS. Here, we describe the endodermal expression pattern of three Nkx6 family genes of which two shows conserved expression in the early pancreatic epithelium. In chicken, Nkx6.1 expression is not restricted to the presumptive pancreatic area but is more broadly expressed in the endoderm. In mice, expression of Nkx6.1 is restricted to the pancreatic epithelium. In both mice and chicken, Nkx6.2 and Pdx1 are expressed in very similar domains, identifying Nkx6.2 as a novel marker of pancreas endoderm. Additionally, our results show that Nkx6.3 is expressed transiently in pancreatic endoderm in chicken but not mouse embryos. At later stages, Nkx6.3 is found in the caudal stomach and rostral duodenum in both species. Finally, we demonstrate that Pdx1 is required for Nkx6.1 but not Nkx6.2 expression in mice and that ectopic Pdx1 can induce Nkx6.1 but not Nkx6.2 or Nkx6.3 expression in anterior chicken endoderm. These results demonstrate that Nkx6.1 lies downstream of Pdx1 in a genetic pathway and that Pdx1 is required and sufficient for Nkx6.1 expression in the early foregut endoderm.
KW - Amino Acid Sequence
KW - Animals
KW - Chick Embryo
KW - Endoderm
KW - Gene Expression Regulation, Developmental
KW - Homeodomain Proteins
KW - Mice
KW - Mice, Mutant Strains
KW - Molecular Sequence Data
KW - Pancreas
KW - Phylogeny
KW - Sequence Homology, Amino Acid
KW - Trans-Activators
KW - Transcription Factors
U2 - 10.1016/j.ydbio.2005.10.001
DO - 10.1016/j.ydbio.2005.10.001
M3 - Journal article
C2 - 16297379
SN - 0012-1606
VL - 288
SP - 487
EP - 501
JO - Developmental Biology
JF - Developmental Biology
IS - 2
ER -