Matrix assembly and function of a C. elegans ZP domain protein

2020-04-20T22:54:03Z (GMT) by Jennifer D Cohen Meera V Sundaram

Apical extracellular matrices (aECMs) shape and protect apical surfaces, like tube lumens and the epidermis. aECMs are rich in Zona Pellucida domain (ZP) proteins, whose dysfunction is associated with human diseases. How ZP proteins assemble in the aECM is unclear.

We are using C. elegans to study how one ZP protein, LET-653, incorporates in the aECM. LET-653 shapes a narrow, single-celled tube and a much larger, multicellular tube, the vulva. Endogenous, tagged LET-653 is visible alongside other aECM components in distinct aECM layers of the vulva lumen. Surprisingly, LET-653 localizes and functions via the ZPc subdomain of the ZP domain. LET-653(ZPc) aECM incorporation is driven by C-terminal cleavage that relieves ZPn-mediated inhibition. Finally, we show that LET-653(ZPc) incorporated into aggregates in vitro. Together, these data offer a novel model for ZP protein aECM assembly.