title: Dopamine signaling regulates the projection patterns in the mouse chiasm.
abstract: Ocular albinism (OA) is characterized by inadequate L-3, 4-dihydroxyphenylalanine (L-DOPA) and dopamine (DA) in the eyes. This study investigated DA-related signaling pathways in mouse chiasm projection patterns and the potential role of ocular albinism type 1 (OA1) and dopamine 1A (D1A) receptors in the optic pathway. In embryonic day (E) E13-E15 retina, most L-DOPA and OA1-positive cells were distributed among Müller glial cells on E13 and retinal ganglion cells (RGC) on E14. In the ventral diencephalon, OA1 and L-DOPA were strongly expressed on the optic chiasm (OC) and optic tract (OT), respectively, but weak on the optic stalk (OS). At E13-E15, DA and D1A staining was predominately expressed in radially arranged cells with a neuronal expression pattern. In the ventral diencephalon, DA and D1A were strongly expressed on the OC, OT and OS. Furthermore, L-DOPA significantly inhibited retinal axon outgrowth in both the dorsal nasal (DN) and ventral temporal (VT) groups. DA inhibited retinal axon outgrowth, which was abolished by the D1A antagonist SCH23390. Brain slice cultures indicated that L-DOPA inhibited axons that crossed at the OC of E13 embryos, which was not abolished by DA. L-DOPA also inhibited axons that crossed at the OC of albino mice. Albino mice exhibited reduced ipsilateral retinal projections compared with C57 pigmented mice. No significant difference was identified in the uncrossed projections of albino mice following L-DOPA and DA expression. Furthermore, transcription factor Zic family member 2 (Zic2) upregulated OA1 mRNA expression. Our findings provide critical insights into DA-related signaling in retinal development.
authors.affiliation: Cancer Research Center, Shenzhen University School of Medicine, PR China; Wuhan University School of Basic Medical Sciences, PR China. Electronic address: jkf_ctt@163.com.
authors.forename: Tingting
authors.initials: T
authors.lastname: Chen
authors.affiliation: Cancer Research Center, Shenzhen University School of Medicine, PR China; Wuhan University School of Basic Medical Sciences, PR China. Electronic address: jackyhu@126.com.
authors.forename: Yunlong
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Shenzhen People's Hospital, PR China. Electronic address: lxt99@126.com.
authors.forename: Xiaotan
authors.initials: X
authors.lastname: Lin
authors.affiliation: Cancer Research Center, Shenzhen University School of Medicine, PR China. Electronic address: 451336657@qq.com.
authors.forename: Xinping
authors.initials: X
authors.lastname: Huang
authors.affiliation: Cancer Research Center, Shenzhen University School of Medicine, PR China. Electronic address: 1518822790@qq.com.
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
authors.affiliation: School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, PR China.. Electronic address: peggleung@cuhk.edu.hk.
authors.forename: Peggy
authors.initials: P
authors.lastname: Leung
authors.affiliation: School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, PR China.. Electronic address: sunonchan@cuhk.edu.hk.
authors.forename: Sun-On
authors.initials: SO
authors.lastname: Chan
authors.affiliation: Wuhan University School of Basic Medical Sciences, PR China.
authors.forename: Deyin
authors.initials: D
authors.lastname: Guo
authors.affiliation: Cancer Research Center, Shenzhen University School of Medicine, PR China. Electronic address: gyjin@szu.edu.cn.
authors.forename: Guangyi
authors.initials: G
authors.lastname: Jin
mesh_terms: D000818:Animals; D004298:Dopamine / Q000378:metabolism*; D004622:Embryo, Mammalian; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D066298:In Vitro Techniques; D007980:Levodopa / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008813:Mice, Inbred ICR; D009474:Neurons / Q000378:metabolism; D009897:Optic Chiasm / Q000196:embryology / Q000378:metabolism*; D009924:Organ Culture Techniques; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism; D017447:Receptors, Dopamine D1 / Q000378:metabolism; D012160:Retina / Q000166:cytology / Q000378:metabolism*; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000378:metabolism; D014795:Visual Pathways / Q000196:embryology / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D017447:Receptors, Dopamine D1; D014157:Transcription Factors; C491811:Zic2 protein, mouse; D007980:Levodopa; D004298:Dopamine
keywords: D1A; Dopamine; L-DOPA; OA1; Zic2