Atlas of Genetics and Cytogenetics in Oncology and Haematology OPEN ACCESS JOURNAL AT INIST-CNRS

Gene Section Mini Review

SMAP1 (stromal membrane-associated 1) Kenji Tanabe, Shunsuke Kon, Masanobu Satake Department of Molecular Immunology, Institute of Development, Aging, and Cancer, Tohoku University, Sendai, Japan (KT, SK, MS)

Published in Atlas Database: March 2008 Online updated version: http://AtlasGeneticsOncology.org/Genes/SMAP1ID42974ch6q13.html DOI: 10.4267/2042/44388 This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 2.0 France Licence. © 2009 Atlas of Genetics and Cytogenetics in Oncology and Haematology

isoform A transcript is constituted by 467, and the other Identity from an isoform B is by 440 aa residues. A protein Other names: FLJ13159; FLJ42245; SMAP-1 diagram shown above represents an isoform B type. HGNC (Hugo): SMAP1 Expression Location: 6q13 Both isoform transcripts are detected in various human Local order: Between D6S455 and D6S1673. tissues. Expression appears to be almost ubiquitous. DNA/RNA Localisation SMAP1 protein is detected in the cytoplasm of cells, Description and appears to be highly concentrated near the plasma The spans an approximately 190 kb region, and is membrane. composed of 11 exons. Function Transcription SMAP1 functions as a GTPase-activating protein for an There is only one transcription initiation site. However, Arf6 GTPase. Arf6 is a Ras-related, small GTPase, and due to , generated are two types of regulates clathrin-dependent and -independent transcripts, isoforms A and B. The length of each endocytosis as well as actin dynamics. SMAP1 is transcript is either 3344 (isoform A) or 3263 nt specifically involved in the Arf6-regulated, clathrin- (isoform B). The isoform A retains, and the isoform B dependent endocytosis. This is achieved by direct lacks in-flame exon 5, respectively. interaction of SMAP1 with clathrin heavy chain. Protein Homology As a highly homologous gene to SMAP1, SMAP2 is Note identified on 1p34.1-35.3. SMAP1 and SMAP2 SMAP1 is a member in the ArfGAP protein family. constitute a small subfamily in the ArfGAP family. SMAP2 protein is specifically involved in the early endosomes to trans-Golgi network transport. Implicated in GAP, an ArfGAP domain; K-rich, a lysine-rich region; CHC, a clathrin heavy chain-binding motif; CALM, a clathrin assembly protein (CALM)-binding domain. t(6;11)(q13;q23) in acute leukemia Description Note Two cases have been reported so far. There are two isoform . One translated from an

Atlas Genet Cytogenet Oncol Haematol. 2009; 13(1) 68 SMAP1 (stromal membrane-associated protein 1) Tanabe K, et al.

Schematic illustration of chimeric MLL-SMAP1 protein. The authentic MLL and SMAP1 proteins are also shown. AT hook, an AT-hook domain; NLS, a nuclear localization signal; MT, a methyltransferase domain; PHD, a plant homeodomain zinc finger; BROMO, a bromo domain; SET, a su(var)3-9, enhancer-of-zeste, trithorax domain. GAP, an ArfGAP domain; K-rich, a lysine-rich region; CHC, a clathrin heavy chain-binding motif; CALM, a clathrin assembly protein (CALM)-binding domain.

Disease Meyer C, Schneider B, Reichel M, Angermueller S, Strehl S, Schnittger S, Schoch C, Jansen MW, van Dongen JJ, Pieters One case is from an M4 subtype of acute myeloid R, Haas OA, Dingermann T, Klingebiel T, Marschalek R. leukemia. A type of leukemia is not described for the Diagnostic tool for the identification of MLL rearrangements other case. including unknown partner . Proc Natl Acad Sci U S A. Hybrid/Mutated gene 2005 Jan 11;102(2):449-54 One leukemia patient possessed the 46, XX, Tanabe K, Torii T, Natsume W, Braesch-Andersen S, t(6;11)(q13;q23) karyotype. In this patient, reciprocal Watanabe T, Satake M. A novel GTPase-activating protein for translocation occured between intron 11 of MLL gene ARF6 directly interacts with clathrin and regulates clathrin- dependent endocytosis. Mol Biol Cell. 2005 Apr;16(4):1617-28 and intron 6 of SMAP1 gene. The chimeric 5'-MLL- SMAP1-3' transcript encodes a chimeric MLL-SMAP1 Natsume W, Tanabe K, Kon S, Yoshida N, Watanabe T, Torii T, Satake M. SMAP2, a novel ARF GTPase-activating protein, protein. interacts with clathrin and clathrin assembly protein and Abnormal protein functions on the AP-1-positive early endosome/trans-Golgi MLL-SMAP1 network. Mol Biol Cell. 2006 Jun;17(6):2592-603 Tanabe K, Kon S, Natsume W, Torii T, Watanabe T, Satake M. References Involvement of a novel ADP-ribosylation factor GTPase- activating protein, SMAP, in membrane trafficking: implications Harrison CJ, Cuneo A, Clark R, Johansson B, Lafage- in cancer cell biology. Cancer Sci. 2006 Sep;97(9):801-6 Pochitaloff M, Mugneret F, Moorman AV, Secker-Walker LM. Ten novel 11q23 chromosomal partner sites. European 11q23 This article should be referenced as such: Workshop participants. Leukemia. 1998 May;12(5):811-22 Tanabe K, Kon S, Satake M. SMAP1 (stromal membrane- Marcos I, Borrego S, Rodríguez de Córdoba S, Galán JJ, associated protein 1). Atlas Genet Cytogenet Oncol Haematol. Antiñolo G. Cloning, characterization and 2009; 13(1):68-69. mapping of the human SMAP1 gene. Gene. 2002 Jun 12;292(1-2):167-71

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