In vivo expression of Nurr1/Nr4a2a in developing retinal amacrine subtypes in zebrafish Tg(nr4a2a:eGFP) transgenics

Abstract

The Nuclear receptor subfamily 4 group A member 2 (Nr4a2) is crucial for the formation or maintenance of dopaminergic neurons in the central nervous system including the retina, where dopaminergic amacrine cells contribute to visual function. Little is known about which cells express Nr4a2 at which developmental stage. Furthermore, whether Nr4a2 functions in combination with other genes is poorly understood. Thus, we generated a novel transgenic to visualize Nr4a2 expression in vivo during zebrafish retinogenesis. A 4.1 kb fragment of the nr4a2a promoter was used to drive green fluorescent protein expression in this Tg(nr4a2a:eGFP) line. In situ hybridization showed that transgene expression follows endogenous RNA expression at a cellular level. Temporal expression and lineages were quantified using in vivo time-lapse imaging in embryos. Nr4a2 expressing retinal subtypes were characterized immunohistochemically. Nr4a2a:eGFP labeled multiple neuron subtypes including 24.5% of all amacrine interneurons. Nr4a2a:eGFP labels all tyrosine hydroxylase labeled dopaminergic amacrine cells, and other nondopaminergic GABAergic amacrine populations. Nr4a2a:eGFP is confined to a specific progenitor lineage identified by sequential expression of the bhlh transcription factor Atonal7 (Atoh7) and Pancreas transcription factor 1a (Ptf1a), and labels postmitotic postmigratory amacrine cells. Thus, developmental Nr4a2a expression indicates a role during late differentiation of specific amacrine interneurons. Tg(nr4a2a:eGFP) is an early marker of distinct neurons including dopaminergic amacrine cells. It can be utilized to assess consequences of gene manipulations and understand whether Nr4a2 only carries out its role in the presence of specific coexpressed genes. This will allow Nr4a2 use to be refined for regenerative approaches.

Differential microRNA expression in the prefrontal cortex of mouse offspring induced by glyphosate exposure during pregnancy and lactation

“…The results of the PCR array indicated that several genes were affected by glyphosate exposure. Nr4a2 is a transcription factor that is highly expressed in the brain and is crucial for the formation or maintenance of dopaminergic neurons in the central nervous system (CNS) ( 55 ). Wnt7b , known to be involved in Wnt signaling, may affect early neural progenitor differentiation by regulating the expression of pro-neural transcription factors, including the T-domain transcription factors Tbr1 and Tbr2 ( 56 ).…”

Microglial peri‐somatic abutments classify two novel types of GABAergic neuron in the inferior colliculus

“…Rabbit anti‐ calretinin (1:1,000; polyclonal; AB5054; lot# 2903043; Millipore; )—according to the manufacturer, this antibody recognizes the 29‐kDa protein in mouse and rat tissues (Su et al., 2010; Yanpallewar et al., 2010). This highly conserved epitope has also been labeled in hamster (Lee et al., 2004), zebrafish (Goodings et al., 2017) and turtle (Parks et al., 2017). We observed labeling consistent with these previous reports.…”

Lmx1a-Dependent Activation of miR-204/211 Controls the Timing of Nurr1-Mediated Dopaminergic Differentiation

“…These include Gdnf [65], Elavl2 [66], Itpr1, Elavl4, Khdrbs1 [67], Rasgef1b [67], and Tcf12 [68]. Some of them are also involved in the differentiation of retinal progenitor cells and in the development of the eye (Nurr1, Elavl2, Plxna2, Rasgef1b, Wnt4, Sox11), tissues in which miR-204/211 shows a relevant role [42,44,66,[69][70][71][72][73] In a precise time window during embryonic development, miR-204/211 holds Nurr1 and its downstream targets repressed, preventing an early DA maturation. Later, during mDAn development, once the precursors are at the right differentiative stage, miR-204/211 expression becomes no longer necessary, Nurr1 expression is "released", and the DA maturation can progress.…”