Purchase this article with an account.
Diane C Slusarski, Lisa Baye, Trudi Westfall, Gunhee Kim, Val C Sheffield; Functional Characterization of the Bardet-Biedl Syndrome1 M390R Mutation in Zebrafish. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):2598.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Bardet-Biedl syndrome (BBS) is a genetically heterogeneous autosomal recessive disorder affecting multiple tissues including the retina. The M390R mutation in the BBS1 gene is the most common disease causing mutation accounting for ~25% of all known BBS cases. The purpose of the current study is to characterize the cellular mechanism by which the mutant BBS1 protein causes disease across and within several tissue types as well as the functional properties of BBS1 M390R in the zebrafish.
To evaluate the functional role of BBS1, protein localization and rescue experiments were performed in the zebrafish by sequential injection of bbs1 antisense oligonucleotides (morpholinos) and either BBS1 or BBS1 M390R RNA. Analysis of embryonic phenotypes include the ciliated Kupffer’s Vesicle (KV), intracellular transport, sensory organs and cardiovascular development and function. Genome editing technologies were used to verify knockdown defects.
We find that BBS1 plays vital roles in cilia formation within the Kupffer’s Vesicle and subsequent left-right asymmetry of visceral organs as well as the formation of sensory systems including the retina and the lateral line neuromasts. We also describe phenotypes not shared with other BBS mutations in cardiovascular function. BBS1 RNA is sufficient to rescue all defects, while BBS1M390R mRNA had differing abilities depending on the tissue type. We show that tagged expressed BBS1 protein is found in the centrioles while BBS1M390R protein is found within the cytoplasm.
These data indicate that the BBS1M390R mutation disrupts normal localization of the protein. Differential activity of the wild type and mutant products to suppress knockdown defects strongly suggests that the location of BBS1 is vital for its proper function in the context of BBS phenotypes. Additionally BBS1 has roles in eye development, cardiovascular function, and neuromast formation.
This PDF is available to Subscribers Only