Distinct and overlapping functions of ptpn11 genes in Zebrafish development.

The PTPN11 (protein-tyrosine phosphatase, non-receptor type 11) gene encodes SHP2, a cytoplasmic PTP that is essential for vertebrate development. Mutations in PTPN11 are associated with Noonan and LEOPARD syndrome. Human patients with these autosomal dominant disorders display various symptoms, including short stature, craniofacial defects and heart abnormalities.

Pair-wise regulation of convergence and extension cell movements by four phosphatases via RhoA.

Various signaling pathways regulate shaping of the main body axis during early vertebrate development. Here, we focused on the role of protein-tyrosine phosphatase signaling in convergence and extension cell movements. We identified Ptpn20 as a structural paralogue of PTP-BL and both phosphatases were required for normal gastrulation cell movements.

Noonan syndrome gain-of-function mutations in NRAS cause zebrafish gastrulation defects.

Noonan syndrome is a relatively common developmental disorder that is characterized by reduced growth, wide-set eyes and congenital heart defects. Noonan syndrome is associated with dysregulation of the Ras-mitogen-activated-protein-kinase (MAPK) signaling pathway. Recently, two mutations in NRAS were reported to be associated with Noonan syndrome, T50I and G60E.

Identification and expression of the family of classical protein-tyrosine phosphatases in zebrafish.

Protein-tyrosine phosphatases (PTPs) have an important role in cell survival, differentiation, proliferation, migration and other cellular processes in conjunction with protein-tyrosine kinases. Still relatively little is known about the function of PTPs in vivo. We set out to systematically identify all classical PTPs in the zebrafish genome and characterize their expression patterns during zebrafish development.

RPTPalpha and PTPepsilon signaling via Fyn/Yes and RhoA is essential for zebrafish convergence and extension cell movements during gastrulation.

Convergence and extension (C&E) cell movements are essential to shape the body axis during vertebrate gastrulation. We have used the zebrafish to assess the role of the receptor protein-tyrosine phosphatases, RPTPalpha and PTPepsilon, in gastrulation cell movements. Both RPTPalpha and PTPepsilon knockdown and ptpra(-/-) embryos show defects in C&E movements.