▪ Abstract This review provides a synthesis that combines data from classical
experimentation and recent advances in our understanding of early eye development …

Cranial placodes are focal regions of thickened ectoderm in the head of vertebrate embryos
that give rise to a wide variety of cell types, including elements of the paired sense organs …

The members of the Six gene family were identified as homologues of Drosophila sine
oculis which is essential for compound‐eye formation. The Six proteins are characterized by …

The sine oculis homeobox (SIX) protein family is a group of evolutionarily conserved
transcription factors that are found in diverse organisms that range from flatworms to …

Patterning of the vertebrate eye appears to be controlled by the mutual regulation and the
progressive restriction of the expression domains of a number of genes initially co …

The homeobox gene sine oculis (so) is essential for visual system formation in Drosophila. A
vertebrate member of the so/Six gene family, Six3, is expressed in the developing eye and …

Studies on the genetic basis of rostral–caudal specification, neural induction, and head
development require knowledge of the relevant gene expression patterns. Gaps in our …

In vertebrates, midline-derived sonic hedgehog and nodal are crucial for the initial proximal-
distal patterning of the eye. The establishment of the distal optic stalk is in turn a prerequisite …

ABSTRACT optix is a new member of the Six/so gene family from Drosophila that contains
both a six domain and a homeodomain. Because of its high amino acid sequence similarity …

Background The heads of annelids (earthworms, polychaetes, and others) and arthropods
(insects, myriapods, spiders, and others) and the arthropod-related onychophorans (velvet …