A role for bHLH transcription factors in retinal degeneration and dysfunction.

Department of Ophthalmology, Baylor College of Medicine, Houston, Texas 77030, USA.
Advances in Experimental Medicine and Biology (Impact Factor: 2.01). 02/2006; 572:155-61. DOI: 10.1007/0-387-32442-9_23
Source: PubMed

ABSTRACT The basic helix loop helix (bHLH) transcription factors collectively mediate cellular differentiation in almost every type
of tissue including the retina (Murre et al. 1989; Jan and Jan 1993; Cepko 1999). Class A factors are ubiquitously expressed throughout mammalian tissue, while the expression
of class B factors are cell type specific. These factors have both a DNA binding domain and helix loop helix domain (HLH)
protein dimerization domain. Class B factors usually heterodimerize with the ubiquitously expressed, bHLH factors, such as
E12/E47. Because of their importance during photoreceptor development, bHLH factors are candidate genes for photoreceptor
degeneration. We have examined the roles of two bHLH factors, both which are expressed during retinal development, but also
share the property of continued expression in the adult retina.

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