Analysis of structure-function relationships of rod monochromacy-associated missense mutations in the CNGA3 subunit of the cone photoreceptor cGMP-gated channel.

2015 Fiscal Year Final Research Report

• Project/Area Number: 25462712
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Ophthalmology
• Research Institution: Shiga University of Medical Science
• Principal Investigator: Muraki Sanae 滋賀医科大学, 医学部, 講師 (90335175)
• Co-Investigator(Kenkyū-buntansha): 上山 久雄 滋賀医科大学, 医学部, 准教授 (30127013)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 杆体１色覚 / cGMP依存性カチオンチャネル / CNGA3 / CNGB3 / パッチクランプ法

Outline of Final Research Achievements

Mutations in the α subunit of cone cyclic nucleotide-gated channel cause rod monochromacy. About 90 missense mutations are known in the α subunit, and they are thought to be useful for elucidation of structure-function relationships in the subunit. HEK293 cells that constitutively express α subunit with a missense mutation were established, and function of the mutant channel was assessed by using a Ca2+-sensor. With regard to function (+) channels, their function was studied in detail by using the patch-clamp technique. With regard to function (-) channels, it was examined whether culture of the cells at low temperature (28℃) could rescue channel function. Some mutant channels showed function by the culture. It was found from the analysis using labeling of cell surface proteins and mutant channels by biotin and HaloTag ligand, respectively, that such a rescue is a consequence of improvement of intracellular trafficking.

Free Research Field

眼科学