Regulation of retinal cell fate specification by multiple transcription factors.
Retinal cell fate specification is strictly regulated by multiple transcription factors. Regarding regulation of cell proliferation and differentiation, basic helix-loop-helix (bHLH) type repressors and activators function in an antagonistic manner. Repressor-type bHLH factors maintain retinal progenitor cells, whereas activator-type bHLH factors promote neuronal cell fate determination. However, bHLH genes alone are not sufficient for acquiring proper neuronal subtype identity. Recent findings have shown that retinal cell fate specification is regulated by combinations of bHLH and homeobox genes. It is conceivable that homeobox genes confer positional identity whereas bHLH genes regulate neuronal determination and differentiation. Moreover, it has been shown that bHLH genes implicated in retinal cell fate determination regulate expression of other bHLH genes, implying that there is a complicated transcription network regulating retinal development.
Ohsawa
Ryosuke
R
Institute for Virus Research, Kyoto University, Shogoin-Kawahara, Sakyo-ku, Kyoto 606-8507, Japan.
Kageyama
Ryoichiro
R
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics*; D002454:Cell Differentiation / Q000235:genetics; D019070:Cell Lineage / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D005801:Genes, Homeobox / Q000235:genetics; D006801:Humans; D012097:Repressor Proteins / Q000235:genetics; D012160:Retina / Q000166:cytology / Q000196:embryology* / Q000378:metabolism*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*
D051792:Basic Helix-Loop-Helix Proteins; D012097:Repressor Proteins