Research Area

The main interest of the lab is the cellular and molecular basis of biomineralization of the endoskeletal spicule of sea urchin embryos. The developing sea urchin embryo generates four micromeres at its vegetal pole during the fourth cell division. These cells form primary mesenchyme, which in turn forms the endoskeletal spicule of the larva. We have developed methods to isolate and purify the spicules, and characterized the organic matrix of the spicules. It is composed of several glycoproteins. We have isolated cDNA clones from an expression vector library that encodes the principal (glyco)protein of the spicule matrix. We are studying the regulation of the expression of this and related genes and are trying to learn more about how the spicule is differentiated and constructed. Recent work utilizes fluorescent labeling and immunoelectron microscopy to follow the import, precipitation, and secretion of calcium and matrix proteins, which form the spicule. The calcium carbonate is precipitated in the cell as amorphous calcium carbonate, then undergoes exocytosis into a privileged extracellular space where it associates with matrix proteins and undergoes a gradual conversion to crystalline calcite. The molecular mechanisms and genes that undergird these processes are being studied.

Current Members

Wilt, Fred H (Principal Investigator/Director)

Contact

Institution: University of California - Berkeley

Address:
Wilt Lab
University of California - Berkeley
Berkeley, CA
94720-3200, USA

Web Page: http://mcb.berkeley.edu/faculty/CDB/wiltf.html

General/Lab Fax: (510) 642-2927