High impact information on SMAP1

• Intriguingly, SMAP1 binds directly to the clathrin heavy chain via its clathrin-box and mutation studies revealed that its GAP domain and clathrin-box both contribute to the role SMAP1 plays in clathrin-dependent endocytosis [1].
• SMAP1 gene localizes to 6q13 and is probably implicated in erythropoiesis, therefore it remains as an interesting candidate gene [2].
• Cloning, characterization and chromosome mapping of the human SMAP1 gene [2].
• The high sequence conservation between murine and human SMAP1, as well as its expression in bone marrow, strongly suggest conserved functions of this protein in both organisms [2].
• The expression of smap-1 in erythropoietic organs as well as the correlation with the erythropoietic activity of the haematopoietic organs suggest that smap-1 is induced in stromal cells by the contact with erythroid cells, defining smap-1 as a key molecule that induced an erythropoietic microenvironment in haematopoietic organs [2].

Biological context of SMAP1

• SMAP1 overexpression had no effect on clathrin-independent endocytosis, however [1].
• This gene is composed of 11 exons and encodes a 468-amino-acid protein, which shows an 86% of homology with the murine smap-1 protein [2].
• By transfection of the anti-sense smap-1 cDNA into the stromal cells, we showed that SMAP-1 may have a stimulatory effect on stroma-supported erythropoiesis [3].

Anatomical context of SMAP1

• Stromal membrane associated protein (smap-1) is a new murine cell surface molecule on the stromal cells [2].
• In this review, we summarize the process of intracellular membrane trafficking, highlighting the roles played by the SMAP gene [4].

Other interactions of SMAP1

• ELOVL5, SMAP1 and GLULD1 were selected on the basis of their location, tissue expression and/or function [5].
• We recently identified the SMAP gene that encodes an ArfGAP and is involved in the endocytosis of TfnR and possibly E-cadherin [4].
• SMAP1 (stromal membrane associated protein 1) was found to be located within RP25 locus and is expressed in retina [5].

References