Matrix Gla protein maintains normal and malignant hematopoietic progenitor cells by interacting with bone morphogenetic protein-4.

Matrix Gla protein (MGP), a modulator of the BMP-SMAD signals, inhibits arterial calcification in a Glu γ-carboxylation dependent manner but the role of MGP highly expressed in a subset of bone marrow (BM) mesenchymal stem/stromal cells is unknown. Here we provide evidence that MGP might be a niche factor for both normal and malignant myelopoiesis. When mouse BM hematopoietic cells were cocultured with mitomycin C-treated BM stromal cells in the presence of anti-MGP antibody, growth of hematopoietic cells was reduced by half, and maintenance of long-term culture-initiating cells (LTC-ICs) was profoundly attenuated.

Translin restricts the growth of pubertal mammary epithelial cells estrogen-independently in mice.

Translin, a ubiquitous RNA/DNA-binding protein that forms a hetero-octamer together with Translin-associated factor X (TRAX), possesses endoribonuclease activity and plays a physiological role in restricting the size and differentiation of mesenchymal precursor cells. However, the precise role of Translin in epithelial cells remains unclear. Here, we show evidence that Translin restricts the growth of pubertal mammary epithelial cells.

Translin modulates mesenchymal cell proliferation and differentiation in mice.

Translin, a highly conserved DNA/RNA binding protein that forms a hetero-octamer together with Translin-associated factor X (TRAX), possesses a broad variety of functions, including RNA processing and DNA repair. Recent studies have reported that Translin is involved in mesenchymal cell physiology. Thus, here we analyzed the intrinsic role of Translin in mesenchymal cell proliferation and differentiation.