SH3GLB1 explained

Endophilin-B1 is a protein that in humans is encoded by the SH3GLB1 gene.^{[1] [2] [3]} Endophilin-B1 belongs to the Bin/Amphiphysin/Rvs167 (BAR) family of proteins and plays a critical role in mitochondrial fission and fusion, as well as in autophagy and apoptosis.^{[4] [5] [6]} Loss of functional endophilin-B1 is seen in many different forms of cancer.^{[7] [8] [9]} The link between carcinogenesis and dysregulation of cell death pathways suggests that endophilin-B1 serves a critical tumor suppressor role in the cell, although the underlying mechanisms are not known.

Structure

In the presence of model biological membranes, endophilin-B1 dimers assemble into helical scaffolds around the membrane and drive its tubulation.

Interactions

In addition to the membrane binding and remodeling properties endophilin-B1 shares with many other BAR proteins, endophilin-B1 interacts with the pro-apoptotic factor Bcl-2-associated X protein (Bax) and SH3GLB2. It has also been shown to interact with a wide variety of proteins through a canonical SH3 domain that enables PxxP motif-containing protein interactions, including Beclin-1, amphiphysin-1, amphiphysin-2, and huntingtin.^{[10] [11]}

References

Further reading

• Maruyama K, Sugano S . Oligo-capping: a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides . Gene . 138 . 1–2 . 171–174 . January 1994 . 8125298 . 10.1016/0378-1119(94)90802-8 .
• Suzuki Y, Yoshitomo-Nakagawa K, Maruyama K, Suyama A, Sugano S . Construction and characterization of a full length-enriched and a 5'-end-enriched cDNA library . Gene . 200 . 1–2 . 149–156 . October 1997 . 9373149 . 10.1016/S0378-1119(97)00411-3 .
• Seki N, Ohira M, Nagase T, Ishikawa K, Miyajima N, Nakajima D, Nomura N, Ohara O . 6 . Characterization of cDNA clones in size-fractionated cDNA libraries from human brain . DNA Research . 4 . 5 . 345–349 . October 1997 . 9455484 . 10.1093/dnares/4.5.345 . free .
• Howard L, Nelson KK, Maciewicz RA, Blobel CP . Interaction of the metalloprotease disintegrins MDC9 and MDC15 with two SH3 domain-containing proteins, endophilin I and SH3PX1 . The Journal of Biological Chemistry . 274 . 44 . 31693–31699 . October 1999 . 10531379 . 10.1074/jbc.274.44.31693 . free .
• Lai CH, Chou CY, Ch'ang LY, Liu CS, Lin W . Identification of novel human genes evolutionarily conserved in Caenorhabditis elegans by comparative proteomics . Genome Research . 10 . 5 . 703–713 . May 2000 . 10810093 . 310876 . 10.1101/gr.10.5.703 .
• Modregger J, Schmidt AA, Ritter B, Huttner WB, Plomann M . Characterization of Endophilin B1b, a brain-specific membrane-associated lysophosphatidic acid acyl transferase with properties distinct from endophilin A1 . The Journal of Biological Chemistry . 278 . 6 . 4160–4167 . February 2003 . 12456676 . 10.1074/jbc.M208568200 . free .
• Lee SY, Wenk MR, Kim Y, Nairn AC, De Camilli P . Regulation of synaptojanin 1 by cyclin-dependent kinase 5 at synapses . Proceedings of the National Academy of Sciences of the United States of America . 101 . 2 . 546–551 . January 2004 . 14704270 . 327184 . 10.1073/pnas.0307813100 . free . 2004PNAS..101..546L .
• Karbowski M, Jeong SY, Youle RJ . Endophilin B1 is required for the maintenance of mitochondrial morphology . The Journal of Cell Biology . 166 . 7 . 1027–1039 . September 2004 . 15452144 . 2172012 . 10.1083/jcb.200407046 .
• Rual JF, Venkatesan K, Hao T, Hirozane-Kishikawa T, Dricot A, Li N, Berriz GF, Gibbons FD, Dreze M, Ayivi-Guedehoussou N, Klitgord N, Simon C, Boxem M, Milstein S, Rosenberg J, Goldberg DS, Zhang LV, Wong SL, Franklin G, Li S, Albala JS, Lim J, Fraughton C, Llamosas E, Cevik S, Bex C, Lamesch P, Sikorski RS, Vandenhaute J, Zoghbi HY, Smolyar A, Bosak S, Sequerra R, Doucette-Stamm L, Cusick ME, Hill DE, Roth FP, Vidal M . 6 . Towards a proteome-scale map of the human protein-protein interaction network . Nature . 437 . 7062 . 1173–1178 . October 2005 . 16189514 . 10.1038/nature04209 . 4427026 . 2005Natur.437.1173R .
• Takahashi Y, Karbowski M, Yamaguchi H, Kazi A, Wu J, Sebti SM, Youle RJ, Wang HG . 6 . Loss of Bif-1 suppresses Bax/Bak conformational change and mitochondrial apoptosis . Molecular and Cellular Biology . 25 . 21 . 9369–9382 . November 2005 . 16227588 . 1265816 . 10.1128/MCB.25.21.9369-9382.2005 .
• Masuda M, Takeda S, Sone M, Ohki T, Mori H, Kamioka Y, Mochizuki N . Endophilin BAR domain drives membrane curvature by two newly identified structure-based mechanisms . The EMBO Journal . 25 . 12 . 2889–2897 . June 2006 . 16763557 . 1500852 . 10.1038/sj.emboj.7601176 .
• Lee JW, Jeong EG, Soung YH, Nam SW, Lee JY, Yoo NJ, Lee SH . Decreased expression of tumour suppressor Bax-interacting factor-1 (Bif-1), a Bax activator, in gastric carcinomas . Pathology . 38 . 4 . 312–315 . August 2006 . 16916719 . 10.1080/00313020600820880 . 25210386 .

Notes and References

1. Pierrat B, Simonen M, Cueto M, Mestan J, Ferrigno P, Heim J . SH3GLB, a new endophilin-related protein family featuring an SH3 domain . Genomics . 71 . 2 . 222–234 . January 2001 . 11161816 . 10.1006/geno.2000.6378 .
2. Cuddeback SM, Yamaguchi H, Komatsu K, Miyashita T, Yamada M, Wu C, Singh S, Wang HG . 6 . Molecular cloning and characterization of Bif-1. A novel Src homology 3 domain-containing protein that associates with Bax . The Journal of Biological Chemistry . 276 . 23 . 20559–20565 . June 2001 . 11259440 . 10.1074/jbc.M101527200 . free .
3. Web site: Entrez Gene: SH3GLB1 SH3-domain GRB2-like endophilin B1.
4. Takahashi Y, Coppola D, Matsushita N, Cualing HD, Sun M, Sato Y, Liang C, Jung JU, Cheng JQ, Mulé JJ, Pledger WJ, Wang HG . 6 . Bif-1 interacts with Beclin 1 through UVRAG and regulates autophagy and tumorigenesis . Nature Cell Biology . 9 . 10 . 1142–1151 . October 2007 . 17891140 . 2254521 . 10.1038/ncb1634 .
5. Karbowski M, Jeong SY, Youle RJ . Endophilin B1 is required for the maintenance of mitochondrial morphology . The Journal of Cell Biology . 166 . 7 . 1027–1039 . September 2004 . 15452144 . 2172012 . 10.1083/jcb.200407046 .
6. Takahashi Y, Karbowski M, Yamaguchi H, Kazi A, Wu J, Sebti SM, Youle RJ, Wang HG . 6 . Loss of Bif-1 suppresses Bax/Bak conformational change and mitochondrial apoptosis . Molecular and Cellular Biology . 25 . 21 . 9369–9382 . November 2005 . 16227588 . 1265816 . 10.1128/MCB.25.21.9369-9382.2005 .
7. Coppola D, Khalil F, Eschrich SA, Boulware D, Yeatman T, Wang HG . Down-regulation of Bax-interacting factor-1 in colorectal adenocarcinoma . Cancer . 113 . 10 . 2665–2670 . November 2008 . 18833585 . 2614910 . 10.1002/cncr.23892 .
8. Coppola D, Oliveri C, Sayegh Z, Boulware D, Takahashi Y, Pow-Sang J, Djeu JY, Wang HG . 6 . Bax-interacting factor-1 expression in prostate cancer . Clinical Genitourinary Cancer . 6 . 2 . 117–121 . September 2008 . 18824435 . 2626142 . 10.3816/CGC.2008.n.018 .
9. Coppola D, Helm J, Ghayouri M, Malafa MP, Wang HG . Down-regulation of Bax-interacting factor 1 in human pancreatic ductal adenocarcinoma . Pancreas . 40 . 3 . 433–437 . April 2011 . 21283040 . 3063470 . 10.1097/MPA.0b013e318205eb03 .
10. Toton E, Lisiak N, Sawicka P, Rybczynska M . Beclin-1 and its role as a target for anticancer therapy . Journal of Physiology and Pharmacology . 65 . 4 . 459–467 . August 2014 . 25179078 .
11. Modregger J, Schmidt AA, Ritter B, Huttner WB, Plomann M . Characterization of Endophilin B1b, a brain-specific membrane-associated lysophosphatidic acid acyl transferase with properties distinct from endophilin A1 . The Journal of Biological Chemistry . 278 . 6 . 4160–4167 . February 2003 . 12456676 . 10.1074/jbc.M208568200 . free .