The Opsin 3/Teleost multiple tissue opsin system: mRNA localization in the retina and brain of medaka ( Oryzias latipes )

Abstract

The photoreceptor protein, opsin, is one of the major components for vision and photoreceptive function in animals. Although many opsins have been discovered from animal genomes, only a few nonimage‐forming functions mediated by opsins have been identified. Understanding the mRNA distribution of photoreceptor proteins is one crucial step in uncovering their photoreceptive function in animals. Here, we focus on the medaka fish (Oryzias latipes) Opsin 3 (Opn3)/Teleost multiple opsin (Tmt) system, which constitutes a separate phylogenetic group, having putative blue light photoreceptors for nonimage‐forming functions. In medaka, there is one opn3 and five tmt‐opsin orthologs. The expression pattern of the opn3/tmt‐opsins in the retina and brain was investigated by in situ hybridization. mRNAs for opn3/tmt‐opsins were distributed in the retinal ganglion cells as well as interneurons and specific brain nuclei. Specifically, hybridization signals were observed in the glutamate decarboxylase 1 (gad1)‐expressing amacrine cells for opn3, tmt1a, tmt1b, and tmt2, in the caudal lobe of the cerebellum for tmt1b and tmt2, in the cranial nerve nuclei for opn3, tmt1a, tmt1b, tmt2, and in the rostral pars distalis (adenohypophysis) for opn3. These expression patterns suggest that blue light sensing in the fish retina and brain may be involved in the integration of visual inputs, vestibular function, somatosensation, motor outputs, and pituitary endocrine regulation.

Multi- and Transgenerational Developmental Impairments Are Induced by Decabromodiphenyl Ethane (DBDPE) in Zebrafish Larvae

“…A variety of genes including opn7d was decreased at the transcriptional level in F2 larvae. Opsin is one of the major components of vision and photoreceptive function in animals. , These changes may also explain the increased malformation rate of anophthalmia in F2 larvae.…”

“…Opsin is one of the major components of vision and photoreceptive function in animals. 67,68 These changes may also explain the increased malformation rate of anophthalmia in F2 larvae.…”

Conserved and diverged asymmetric gene expression in the brain of teleosts

“…In zebrafish, numerous genes have been described that are either expressed specifically or largely specifically in subnuclei of the dorsal habenulae (dHb), in all dHb neurons or in dHb neuronal precursor cells. Of these, we isolated the medaka orthologues for kctd12.1 ( Gamse et al, 2003 ; Sato et al, 2021 ) and nrp1 expressed predominantly in lateral neurons of the dorsal habenulae (dHbl) ( Kuan et al, 2007 ), cntn2 ( Carl et al, 2007 ) and slc18a3b/vachtb as markers for medial neurons of the dorsal habenulae (dHbm) ( Hong et al, 2013 ), slc17a6b/vglut2 expressed in all habenular neurons ( Thisse et al, 2005 ) and cxcr4b in dorsal habenular precursors ( Roussigné et al, 2009 ). In addition, we re-assessed the expression of medaka prox1a (formerly named prox1b ), which was reported to be right-dominantly asymmetric in the habenulae ( Deguchi et al, 2009 ).…”

Involvement of a Basic Helix-Loop-Helix Gene BHLHE40 in Specification of Chicken Retinal Pigment Epithelium

“…Whole-mount ISH (WISH) was performed according to Kawaue et al [ 19 ] by the use of a semiautomatic ISH machine (HS-5100; Aloka, Tokyo, Japan) ( Figure 1 A–D’, E). The ISH on sections was performed according to Sato et al [ 20 ]. Each RNA probe was used at a concentration of 0.67 μg/mL (WISH) or 0.17 μg/mL (sections) in hybridization buffer.…”