Ensconsin Explained

Ensconsin is a protein that in humans is encoded by the MAP7 gene.^{[1] [2]}

Function

The product of this gene is a microtubule-associated protein that is predominantly expressed in cells of epithelial origin. Microtubule-associated proteins are thought to be involved in microtubule dynamics, which is essential for cell polarization and differentiation. This protein has been shown to be able to stabilize microtubules, and may serve to modulate microtubule functions. Studies of the related mouse protein also suggested an essential role in microtubule function required for spermatogenesis.

In addition, MAPs also play a role in regulating cellular transport. MAP7 is a necessary cofactor to activate and subsequently transport cargos by Kinesin-1. ^{[3] [4]}

MAP7's effect on Dynein is still debated.^{[5] [6]}

Interactions

MAP7 has been shown to interact with TRPV4.^[7]

Further reading

• Masson D, Kreis TE . Binding of E-MAP-115 to microtubules is regulated by cell cycle-dependent phosphorylation . The Journal of Cell Biology . 131 . 4 . 1015–1024 . November 1995 . 7490279 . 2200015 . 10.1083/jcb.131.4.1015 .
• Fabre-Jonca N, Viard I, French LE, Masson D . Upregulation and redistribution of E-MAP-115 (epithelial microtubule-associated protein of 115 kDa) in terminally differentiating keratinocytes is coincident with the formation of intercellular contacts . The Journal of Investigative Dermatology . 112 . 2 . 216–225 . February 1999 . 9989799 . 10.1046/j.1523-1747.1999.00500.x . free .
• Bulinski JC, Odde DJ, Howell BJ, Salmon TD, Waterman-Storer CM . Rapid dynamics of the microtubule binding of ensconsin in vivo . Journal of Cell Science . 114 . Pt 21 . 3885–3897 . November 2001 . 11719555 . 10.1242/jcs.114.21.3885 .
• Penttilä TL, Parvinen M, Paranko J . Microtubule-associated epithelial protein E-MAP-115 is localized in the spermatid manchette . International Journal of Andrology . 26 . 3 . 166–174 . June 2003 . 12755995 . 10.1046/j.1365-2605.2003.00406.x . free .
• Vanier MT, Deck P, Stutzmann J, Gendry P, Arnold C, Dirrig-Grosch S, Kedinger M, Launay JF . 6 . Expression and distribution of distinct variants of E-MAP-115 during proliferation and differentiation of human intestinal epithelial cells . Cell Motility and the Cytoskeleton . 55 . 4 . 221–231 . August 2003 . 12845596 . 10.1002/cm.10124 .
• Suzuki M, Hirao A, Mizuno A . Microtubule-associated [corrected] protein 7 increases the membrane expression of transient receptor potential vanilloid 4 (TRPV4) . The Journal of Biological Chemistry . 278 . 51 . 51448–51453 . December 2003 . 14517216 . 10.1074/jbc.M308212200 . free .
• Sood R, Bader PI, Speer MC, Edwards YH, Eddings EM, Blair RT, Hu P, Faruque MU, Robbins CM, Zhang H, Leuders J, Morrison K, Thompson D, Schwartzberg PL, Meltzer PS, Trent JM . 6 . Cloning and characterization of an inversion breakpoint at 6q23.3 suggests a role for Map7 in sacral dysgenesis . Cytogenetic and Genome Research . 106 . 1 . 61–67 . 2004 . 15218243 . 10.1159/000078563 . 39067023 .
• Nousiainen M, Silljé HH, Sauer G, Nigg EA, Körner R . Phosphoproteome analysis of the human mitotic spindle . Proceedings of the National Academy of Sciences of the United States of America . 103 . 14 . 5391–5396 . April 2006 . 16565220 . 1459365 . 10.1073/pnas.0507066103 . free . 2006PNAS..103.5391N .
• Beausoleil SA, Villén J, Gerber SA, Rush J, Gygi SP . A probability-based approach for high-throughput protein phosphorylation analysis and site localization . Nature Biotechnology . 24 . 10 . 1285–1292 . October 2006 . 16964243 . 10.1038/nbt1240 . 14294292 .
• Olsen JV, Blagoev B, Gnad F, Macek B, Kumar C, Mortensen P, Mann M . Global, in vivo, and site-specific phosphorylation dynamics in signaling networks . Cell . 127 . 3 . 635–648 . November 2006 . 17081983 . 10.1016/j.cell.2006.09.026 . 7827573 . free .

Notes and References

1. Masson D, Kreis TE . Identification and molecular characterization of E-MAP-115, a novel microtubule-associated protein predominantly expressed in epithelial cells . The Journal of Cell Biology . 123 . 2 . 357–371 . October 1993 . 8408219 . 2119845 . 10.1083/jcb.123.2.357 .
2. Web site: Entrez Gene: MAP7 microtubule-associated protein 7.
3. Hooikaas PJ, Martin M, Mühlethaler T, Kuijntjes GJ, Peeters CA, Katrukha EA, Ferrari L, Stucchi R, Verhagen DG, van Riel WE, Grigoriev I, Altelaar AF, Hoogenraad CC, Rüdiger SG, Steinmetz MO, Kapitein LC, Akhmanova A . 6 . MAP7 family proteins regulate kinesin-1 recruitment and activation . The Journal of Cell Biology . 218 . 4 . 1298–1318 . April 2019 . 30770434 . 10.1083/jcb.201808065 . 6446838 .
4. Monroy BY, Tan TC, Oclaman JM, Han JS, Simó S, Niwa S, Nowakowski DW, McKenney RJ, Ori-McKenney KM . 6 . A Combinatorial MAP Code Dictates Polarized Microtubule Transport . Developmental Cell . 53 . 1 . 60–72.e4 . April 2020 . 32109385 . 10.1016/j.devcel.2020.01.029 . 7181406 .
5. Monroy BY, Sawyer DL, Ackermann BE, Borden MM, Tan TC, Ori-McKenney KM . Competition between microtubule-associated proteins directs motor transport . Nature Communications . 9 . 1 . 1487 . April 2018 . 29662074 . 5902456 . 10.1038/s41467-018-03909-2 . 2018NatCo...9.1487M .
6. Ferro LS, Fang Q, Eshun-Wilson L, Fernandes J, Jack A, Farrell DP, Golcuk M, Huijben T, Costa K, Gur M, DiMaio F, Nogales E, Yildiz A . 6 . Structural and functional insight into regulation of kinesin-1 by microtubule-associated protein MAP7 . Science . 375 . 6578 . 326–331 . January 2022 . 35050657 . 10.1126/science.abf6154 . 8985661 . 2022Sci...375..326F .
7. Suzuki M, Hirao A, Mizuno A . Microtubule-associated [corrected] protein 7 increases the membrane expression of transient receptor potential vanilloid 4 (TRPV4) . The Journal of Biological Chemistry . 278 . 51 . 51448–51453 . December 2003 . 14517216 . 10.1074/jbc.M308212200 . free .