High impact information on Six3

• Six3 functions in anterior neural plate specification by promoting cell proliferation and inhibiting Bmp4 expression [1].
• On its own, Six3 is unable to induce neural tissue in animal caps, but it can do so in combination with Otx2 [1].
• In this study, we show that exogenous Six3 can expand the anterior neural plate in both Xenopus and zebrafish, and that this occurs in part through Six3-dependent transcriptional regulation of the cell cycle regulators cyclinD1 and p27Xic1, as well as the anti-neurogenic genes Zic2 and Xhairy2 [1].
• In cell cycle, Six3 is also reported as pro-proliferation gene by binding to geminin. The interaction is reported to be a stronger than Cdt1-Geminin itself. [2]
• However, Six3 can still expand the neural plate in the presence of cell cycle inhibitors and we show that this is likely to be due to its ability to repress the expression of Bmp4 in ectoderm adjacent to the anterior neural plate [1].
• The vertebrate Six3 gene a homeobox gene of the Six-family, plays a crucial role in early eye and forebrain development [3].
• Along with other eye transcription factors (ET, Rx1, Pax6, Lhx2, tll), Six3 can induce ectopic eye formation. [4]

Biological context of Six3

• These results suggest a very early role for Six3 in specification of the anterior neural plate, through the regulation of cell proliferation and the inhibition of BMP signalling [1].

References