Marisa Otegui

Marisa Otegui
Associate Professor

Associate Professor of Botany and Genetics

Ph.D., University of La Plata, Argentina, 1996
Postdoctoral Research: University of Colorado-Boulder 

Lab website: http://www.botany.wisc.edu/otegui/welcome.html

Address: B119 Birge Hall

Telephone: 608-265-5703

E-mail:

Department: Botany and Genetics

Research Interests

Cellular trafficking and signaling

Research Fields

Cell Biology
Development
Plants

Research Description:

We are interested in structural and functional aspects of multivesicular bodies (MVBs) in plant cells. MVBs are endosomes that consist of a limiting membrane and internal vesicles. The internal vesicles arise from invaginations of the limiting membrane and carry membrane proteins targeted for degradation in the lysosome/vacuole. MVBs play a crucial role in both the endocytic and the secretory pathways of all eukaryotic cells, sorting proteins for degradation or recycling, downregulating receptors, and mediating the transport of proteins to the vacuole/lysosome. Thus, MVB functions are tightly related to cell signaling, differentiation, and transport of vacuolar cargoes. 

The endosomal invagination process is unique because, unlike most vesiculation processes characterized to date, the vesiculating membrane buds away from the cytoplasm. This invagination process requires the concentration of membrane proteins into specific membrane domains and the initiation of budding into the MVB lumen. Multisubunit protein complexes called endosomal sorting complexes required for transport I, II, and III (ESCRT-I, -II,-III) mediate membrane protein sorting into MVB internal vesicles. In plants, MVBs have been adapted to serve both the same functions as in yeast and mammalian cells as well as unique plant functions. In particular, plant MVBs appear to play a central role in the transport and processing of vacuolar storage proteins and recycling of membrane removed from the cell plate during cytokinesis. We are addressing questions such as: How many classes of endosomal compartments exist in plants? How do MVBs arise? What are their functions in different cell types? What is the molecular machinery responsible for MVB sorting and invagination? 

We are interested in structural and functional aspects of multivesicular bodies (MVBs) in plant cells. MVBs are endosomes that consist of a limiting membrane and internal vesicles. The internal vesicles arise from invaginations of the limiting membrane and carry membrane proteins targeted for degradation in the lysosome/vacuole. MVBs play a crucial role in both the endocytic and the secretory pathways of all eukaryotic cells, sorting proteins for degradation or recycling, downregulating receptors, and mediating the transport of proteins to the vacuole/lysosome. Thus, MVB functions are tightly related to cell signaling, differentiation, and transport of vacuolar cargoes. 

The endosomal invagination process is unique because, unlike most vesiculation processes characterized to date, the vesiculating membrane buds away from the cytoplasm. This invagination process requires the concentration of membrane proteins into specific membrane domains and the initiation of budding into the MVB lumen. Multisubunit protein complexes called endosomal sorting complexes required for transport I, II, and III (ESCRT-I, -II,-III) mediate membrane protein sorting into MVB internal vesicles. In plants, MVBs have been adapted to serve both the same functions as in yeast and mammalian cells as well as unique plant functions. In particular, plant MVBs appear to play a central role in the transport and processing of vacuolar storage proteins and recycling of membrane removed from the cell plate during cytokinesis. We are addressing questions such as: How many classes of endosomal compartments exist in plants? How do MVBs arise? What are their functions in different cell types? What is the molecular machinery responsible for MVB sorting and invagination? 

Representative Publications:

Search PubMed for more publications by Marisa Otegui

Reyes FC, Buono R, Otegui MS. 2011. Plant endosomal trafficking pathways. Current Opinion in Plant Biology 14: 666-73.

Capoen, W., Sun, J., Hirsch, S., Otegui, M.S., Venkateshwaran, M., Miwa, H., Downie, J.A., Ané, J.-M., Oldroyd, G.E.D. 2011. Nuclear membranes control symbiotic calcium signalling of legumes. Proc Natl Acad Sci U S A. 108:14348-53.

Otegui, M.S. 2011. Electron tomography and immunogold labeling as tools to analyze de novo assembly of plant cell walls. Methods Mol Biol. 715:123-40.

Reyes, F.C., Chung, T., Holding, D., Jung, R., Vierstra, R., Otegui, M.S. 2011. Delivery of prolamins to the protein storage vacuole in maize aleurone cells. The Plant Cell 23:769-84.

Wu, G., Wang, X, Li, X., Kasahara, H., Kamiya, Y., Otegui, M.S. and Chory, J. 2011. Methylation of a phosphatase specifies dephosphorylation and degradation of activated brassinosteroid receptors. Science Signaling 4:ra29.

Wu, G., Otegui, M.S., Spalding, E.P. 2010. Trafficking of ABCB19, a plant multidrug resistance-like transporter required for auxin-mediated root cell elongation, requires the ER-localized TWD1 immunophilin. The Plant Cell: 22: 3295-3304.

Reyes FC, Sun B, Guo H, Gruis D, Otegui MS. 2010. Agrobacterium tumefaciens-mediated transformation of maize endosperm as a tool to study endosperm cell biology. Plant Physiology 153: 624-631.

Haruta, M., Burch, H.L., Nelson, R.B., Barrett-Wilt G., Kline, K.G., Mohsin, S.B., Young, J.C., Otegui, M.S., Sussman, M. 2010. Molecular characterization of mutant Arabidopsis plants with reduced plasma membrane proton pump activity. Journal of Biological Chemistry 285:17918-29.

Peer, W.A., Hosein, F.N., Bandyopadhyay, A., Makam, S.N., Otegui, M.S., Lee, G.J., Blakeslee, J.J., Cheng, Y., Titapiwatanakun, B., Yakubov, B., Bangari, B., Murphy, A.S. 2009. Mutation of the membrane-associated M1 protease APM1 results in distinct embryonic and seedling developmental defects in Arabidopsis. The Plant Cell: 21:1693-721.

Spitzer, C., Reyes, F.C., Buono, R., Sliwinski, M.K., Haas, T.J., Otegui, M.S. 2009. The ESCRT-related CHMP1A and B proteins mediate multivesicular body sorting of auxin carriers and are required for plant development. The Plant Cell 21: 749-766.Ebine, K. Okatani, Y.,

Uemura, T., Goh, T., Shoda, K., Niihama, M., Terao Morita, M., Spitzer, C., Otegui, M.S., Nakano, A. and Ueda, T. 2008. A SNARE complex unique to seed plants is required for vacuole biogenesis and seed development of Arabidopsis thaliana. The Plant Cell 20: 3006-21