AUTHOR=Xu Jing , Li Zhigang , Yang Haorui , Yang Xiaohong , Chen Cuixia , Li Hui 

TITLE=Genetic Diversity and Molecular Evolution of a Violaxanthin De-epoxidase Gene in Maize

JOURNAL=Frontiers in Genetics

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2016.00131

DOI=10.3389/fgene.2016.00131

ISSN=1664-8021

ABSTRACT=<p>Violaxanthin de-epoxidase (VDE) has a critical role in the carotenoid biosynthesis pathway, which is involved in protecting the photosynthesis apparatus from damage caused by excessive light. Here, a <italic>VDE</italic> gene in maize, <italic>ZmVDE1</italic>, was cloned and shown to have functional domains in common with the gramineous VDE protein. Candidate gene association analysis indicated that no polymorphic sites in <italic>ZmVDE1</italic> were significant association with any of the examined carotenoid-related traits at <italic>P</italic> = 0.05 in an association panel containing 155 maize inbred lines. Nucleotide diversity analysis of <italic>VDE1</italic> in maize and teosinte indicated that its exon had less genetic variation, consistent with the conserved function of <italic>VDE1</italic> in plants. In addition, dramatically reduced nucleotide diversity, fewer haplotypes and a significantly negative parameter deviation for Tajima’s <italic>D</italic> test of <italic>ZmVDE1</italic> in maize and teosinte suggested that a potential selective force had acted across the <italic>ZmVDE1</italic> locus. We further identified a 4.2 Mb selective sweep with low recombination surrounding the <italic>ZmVDE1</italic> locus that resulted in severely reduced nucleotide diversity on chromosome 2. Collectively, natural selection and the conserved domains of <italic>ZmVDE1</italic> might show an important role in the xanthophyll cycle of the carotenoid biosynthesis pathway.</p>