Functional but abnormal adult erythropoiesis in the absence of the stem cell leukemia gene.

Previous studies have indicated that the stem cell leukemia gene (SCL) is essential for both embryonic and adult erythropoiesis. We have examined erythropoiesis in conditional SCL knockout mice for at least 6 months after loss of SCL function and report that SCL was important but not essential for the generation of mature red blood cells. Although SCL-deleted mice were mildly anemic with increased splenic erythropoiesis, they responded appropriately to endogenous erythropoietin and hemolytic stress, a measure of late erythroid progenitors.

SCL is required for normal function of short-term repopulating hematopoietic stem cells.

The stem cell leukemia (SCL) gene is essential for the development of hematopoietic stem cells in the embryo. Here, we used a conditional gene targeting approach to examine the function of SCL in adult hematopoietic stem cells (HSCs). Flow cytometry of bone marrow from SCL-deleted mice demonstrated a 4-fold increase in number of Lin(neg) c-kit(+) Sca-1(+) cells.

Stromal interaction molecule 1 (STIM1), a transmembrane protein with growth suppressor activity, contains an extracellular SAM domain modified by N-linked glycosylation.

Stromal interaction molecule 1 (STIM1) is a cell surface transmembrane glycoprotein implicated in tumour growth control and stromal-haematopoietic cell interactions. A single sterile alpha motif (SAM) protein-protein interaction domain is modelled within its extracellular region, a subcellular localisation not previously described for other SAM domain-containing proteins. We have defined the transmembrane topology of STIM1 by determining the sites of N-linked glycosylation.

Identification and characterization of the STIM (stromal interaction molecule) gene family: coding for a novel class of transmembrane proteins.

STIM1 (where STIM is stromal interaction molecule) is a candidate tumour suppressor gene that maps to human chromosome 11p15.5, a region implicated in a variety of cancers, particularly embryonal rhabdomyosarcoma. STIM1 codes for a transmembrane phosphoprotein whose structure is unrelated to that of any other known proteins.

STIM1: a novel phosphoprotein located at the cell surface.

STIM1 is a novel candidate growth suppressor gene mapping to the human chromosome region 11p15.5 that is associated with several malignancies. STIM1 overexpression studies in G401 rhabdoid tumour, rhabdomyosarcoma and rodent myoblast cell lines causes growth arrest, consistent with a potential role as a tumour growth suppressor.