Congenital asplenia in mice and humans with mutations in a Pbx/Nkx2-5/p15 module.
Journal:
Dev. Cell 2012 MayAuthors:
Koss M, Bolze A, Brendolan A, Saggese M, Capellini TD, Bojilova E, Boisson B, Prall OW, Elliott DA, Solloway M, Lenti E, Hidaka C, Chang CP, Mahlaoui N, Harvey RP, Casanova JL, Selleri L
Abstract
The molecular determinants of spleen organogenesis and the etiology of isolated congenital asplenia (ICA), a life-threatening human condition, are unknown. We previously reported that Pbx1 deficiency causes organ growth defects including asplenia. Here, we show that mice with splenic mesenchyme-specific Pbx1 inactivation exhibit hyposplenia. Moreover, the loss of Pbx causes downregulation of Nkx2-5 and derepression of p15Ink4b in spleen mesenchymal progenitors, perturbing the cell cycle. Removal
...[more] of p15Ink4b in Pbx1 spleen-specific mutants partially rescues spleen growth. By whole-exome sequencing of a multiplex kindred with ICA, we identify a heterozygous missense mutation (P236H) in NKX2-5 showing reduced transactivation in vitro. This study establishes that a Pbx/Nkx2-5/p15 regulatory module is essential for spleen development.[less]
Mesh Headings:
Adolescent, Amino Acid Sequence, Animals, Cells, Cultured, Cyclin-Dependent Kinase Inhibitor p15, DNA-Binding Proteins, Exome, Female, Gene Expression Profiling, Gene Expression Regulation, Developmental, Homeodomain Proteins, Humans, Infant, Male, Mice, Mice, Transgenic, Molecular Sequence Data, Mutation, Missense, Pedigree, Proto-Oncogene Proteins, Spleen, Splenic Diseases, Transcription Factors