The role of Zebrafish AHR repressor1 (AHRR1) in forebrain and retina development

• Main Authors: Ying-Lin Tsai, 蔡瑩霖
• Other Authors: Chin-Hwa Hu
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/07363633590751332755

碩士 === 國立臺灣海洋大學 === 生物科技研究所 === 96 === The aryl hydrocarbon receptor repressor(AHRR) is a new member of the bHLH-PAS superfamily. In mammalian and several teleost species, AHRR acted as a repressor of AH receptor (AHR) which competed with AHR for binding to ARNT, and made it unavailable to AHR. The AHRR-ARNT complex also bound to the xenobiotic response elements (XREs) but did not activate the target genes. In zebrafish, the two AHRR orthologs, AHRR1 and AHRR2, have also been suggested to work in a negative autoregulatory loop of AHRsignaling pathway, but it still remains to be confirmed. During developing stage, zebrafish ahrr1 and ahrr2 is mainly expressed in brain and retina region at 24h~120h postfertilization. In addition, knockdown of AHRR1 function resulted in severe pericardial edema, small head and small eyes, It appears that AHRR1 has important role in embryo development. Here, two ahrr1-specific antisenese morpholino oligonucleotide, ahrr1-MO1 and ahrr1-MO2, were designed to block AHRR1 protein translation and the expression patterns of the forebrain and retina-related genes were analyzed by whole mount RNA in situ hybridization. The results showed that blockage of ahrr1 translation interfered the hypothalamus endocrine cells and late-stage retina development. It suggests that AHRR1 may have an important role in neuroendocrine system development and retina neural cells differentiation. It is the first time to reveal the function of AHRR in vertebrate hypothalamus and retina development.