TY - JOUR T1 - Krüppel-like factor 4 (KLF4) is not required for retinal cell differentiation JF - eneuro JO - eneuro DO - 10.1523/ENEURO.0117-15.2016 SP - ENEURO.0117-15.2016 AU - Jiahua Fang AU - Peter X. Shaw AU - Yan Wang AU - Jeffrey L. Goldberg Y1 - 2016/01/13 UR - http://www.eneuro.org/content/early/2016/01/13/ENEURO.0117-15.2016.abstract N2 - During early vertebrate eye development, a regulatory network of transcription factors regulates retinal cell differentiation and survival into adulthood. Among those factors, Krüppel-like factor 4 (KLF4) plays a dual roles of maintaining the stem cell status of retinal progenitors cells and represses intrinsic axon regeneration ability in retinal ganglion cells (RGCs) after injury. This study further investigated whether KLF4 plays a role in early retinal cell differentiation or survival into adulthood. We examined different types of retinal neurons, including RGCs, amacrine cells, bipolar cells, Müller cells, and photoreceptor cells in adult mice in which KLF4 was conditionally deleted in early retinal development using Chx10-promoted Cre by immunohistochemistry. We compared the numbers of retinal neurons and the thickness of photoreceptor and nerve fiber layers between Chx10-Cre driven KLF4-deletion and wild type mice. There was no significant difference in cell number among any of the retinal cell types or in photoreceptor layer thickness with KLF4 deletion during early development. The thickness of axon bundles in the nerve fiber layer in the Chx10 conditional KLF4 knockout was greater than that in wild type mice. These results suggest that KLF4 is not required for retinal cell differentiation or survival, but does normally limit retinal ganglion cell axon bundle thickness. These data support a hypothesis that KLF4 suppresses axon growth during development.Significance Statement: Although it has been well studied for its role in reprogramming somatic cells into induced pluripotent stem cells (iPSCs) and the repression of axon regeneration of optic nerve injury, whether KLF4 play any role in retinal neuronal differentiation and survival into the adulthood is still poorly understood. This study provides a line of evidence that the absence of KLF4 in early development does not affect retinal neuron differentiation to designated cell types. ER -