Extracellular Engrailed participates in the topographic guidance of retinal axons in vivo.

Engrailed transcription factors regulate the expression of guidance cues that pattern retinal axon terminals in the dorsal midbrain. They also act directly to guide axon growth in vitro. We show here that an extracellular En gradient exists in the tectum along the anterior-posterior axis.

Progressive loss of dopaminergic neurons in the ventral midbrain of adult mice heterozygote for Engrailed1: a new genetic model for Parkinson's disease?

Engrailed1 is a developmental gene of the homeogene family that controls the survival of midbrain dopaminergic neurons throughout life. Since these neurons have been crucially implicated in Parkinson's disease (PD), transgenic mice lacking one En1 allele could be of particular interest for the development of an animal model for PD. We showed in En1+/- mice, some traits reminiscent of PD such as (1) a progressive loss of mesencephalic dopaminergic (DA) neurons, and (2) motor deficits, anhedonia, decreased social interactions and depression-like behaviours.

The topological role of homeoproteins in the developing central nervous system.

Homeogenes encode homeoprotein transcription factors that have fundamental roles in development. They are key players in genetic networks that lay out the body plan and also determine morphology and physiology at the cellular and multicellular level. However, homeoproteins share activities that extend beyond transcription, including translation regulation and signalling.

Progressive loss of dopaminergic neurons in the ventral midbrain of adult mice heterozygote for Engrailed1.

Engrailed1 and Engrailed2 (En1 and En2) are two developmental genes of the homeogene family expressed in the developing midbrain. En1 and, to a lesser degree, En2 also are expressed in the adult substantia nigra (SN) and ventral tegmental area (VTA), two dopaminergic (DA) nuclei of the ventral midbrain. In an effort to study En1/2 adult functions, we have analyzed the phenotype of mice lacking one En1 allele in an En2 wild-type context.