Assistant Professor of Biology, University of Massachusetts
Ph.D.: University of Wisconsin, Madison, 1992
Molecular and cellular mechanisms of vertebrate retinal development and retinal disease.
Our efforts at understanding retinal development address two fundamental questions: (1) How are different retinal cell types generated? (2) How are those cells organized into a functional tissue? Early in development, the retina consists of a seemingly homogenous population of multipotential progenitor cells. Later, this population generates many different cell types that are organized into specific cell layers and finally functional connections are made. We use zebrafish, which is a good model system for human retinal development; they have the same cell types and cells are organized in the same way. We are using genetics in zebrafish to identify genes that regulate the proliferation, differentiation, survival, and organization of retinal cells. The current focus of our lab is to understand the role of cell polarity in organization of the retina during development, and how loss of polarity can lead to degenerative retinal disease. We are examining the role of a novel gene we identified, called mosaic eyes (moe) , which plays a role in polarity. When this gene is mutated in zebrafish, the layers in the retina fail to form even though all the cell types that normally comprise the retina are present. We are using biochemistry and molecular and cell biological approaches to understand how moe and other molecules involved in establishing cell polarity regulate layer formation and cell polarity during development. We are also examining the role of moe in photoreceptor morphogenesis and photoreceptor degeneration.
Jensen, A.M. (2005) Potential roles for BMP and Pax genes in the development of iris smooth muscle. Developmental Dynamics 232:385-92.
Jensen, A.M . and Westerfield, M. (2004) Zebrafish Mosaic eyes is a novel FERM protein required for retinal lamination and retinal pigmented epithelial tight junction formation. Current Biology 14:711-717.
Jensen, A.M. , Walker, C., and Westerfield, M. 2001. Mosaic eyes : a zebrafish gene required in pigmented epithelium for apical localization of retinal cell divisions and lamination. Development 128: 95-105.
Wallace, V.A. and A.M. Jensen . 1998. IBMX, taurine, and 9-cis retinoic acid act on postmitotic cells to accelerate rod photoreceptor differentiation. Experimental Eye Research 69: 617-27.
Jensen, A.M. and Raff, M.C. 1997. Continuous observation of multipotential retinal progenitor cells in clonal density culture. Developmental Biology 188: 267-279.
Jensen, A.M. and Wallace, V. A. 1997. Expression of Sonic Hedgehog and its putative role as a precursor cell mitogen in the developing mouse retina. Development 124: 363-371.