Study And Analysis Of Superfolder Venus Yellow Fluorescent Protein And Its Expression In Chlamydomonas Reinhardtii

Fluorescent proteins(FP)have been an indispensable tool in biological research.Likewise,they have been gradually adopted into the studies of micro algae such as Chlamydomonas reinhardtii.Several FPs,for instance mCherry,tdTomato,Venus or CrYFP,CrGFP,mTagBFP and PtCrCFP have been successfully employed as gene reporters in the nuclear transformation of C.reinhardtii mutant strains UVM4 and UVM11.However,it is still difficult to use FP as a reporter gene in wide-type algae,although we can efficiently transform and integrate foreign genes into the nuclear genome of C.reinhardtii,the expression efficiencies of exogenous genes are very low.Here,we developed a variant version of FP that can achieve an efficient and stable expression in C.reinhardtii.Our construct,named superfolder Venus yellow fluorescent protein(sfVenus),was based on both Venus and superfolder GFP.Our results demonstrated that the sfVenus reporter accumulated more efficiently in C.reinhardtii cells,roughly 1.5-fold of Venus.In addition,our experiment also explored the expression of two and three tandem sfVenuses and it is proved that the expression of them in C.reinhardtii is very difficult,especially gene2 sfVenuses only expressed one sfVenus and the fluorescence intensity was not as good as the protein expressed by gene sfVenus.