Stromal membrane-associated protein 1 (SMAP1)

Stromal membrane-associated protein 1 (SMAP1) is a highly conserved intracellular protein that acts as a GTPase-activating protein (GAP) for ARF6, a member of the ADP-ribosylation factor family of small GTPases. SMAP1 regulates the formation and trafficking of clathrin-coated vesicles, processes essential for endocytosis, membrane recycling, and protein sorting between subcellular compartments including the trans-Golgi network. SMAP1 is also involved in the interaction between stromal and erythroid cells, contributing to the hematopoietic microenvironment, and is expressed in hematopoietic organs such as bone marrow. Its deficiency in animal models leads to abnormal receptor trafficking, enhanced transferrin endocytosis, impaired lysosomal sorting of c-KIT, and predisposition to hematological conditions reminiscent of myelodysplastic syndrome and acute myeloid leukemia. Chromosomal translocations involving SMAP1 have been linked with aplastic anemia and certain leukemias. In non-mammalian systems, SMAP1 homologs function in polarized membrane trafficking, further underscoring their role in directed protein sorting in multicellular organisms. Acting as both a regulator of membrane dynamics and a tumor suppressor, SMAP1 is crucial for normal cellular homeostasis and tissue function.

Other names

SMAP1SMAP-1FLJ13159stromal membrane-associated protein 1stromal membrane-associated GTPase-activating protein 1