AUTHOR=Feng Xingxing , Yang Suxin , Tang Kuanqiang , Zhang Yaohua , Leng Jiantian , Ma Jingjing , Wang Quan , Feng Xianzhong 

TITLE=GmPGL1, a Thiamine Thiazole Synthase, Is Required for the Biosynthesis of Thiamine in Soybean

JOURNAL=Frontiers in Plant Science

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2019.01546

DOI=10.3389/fpls.2019.01546

ISSN=1664-462X

ABSTRACT=<p>Thiamine is an essential cofactor in several enzymatic reactions for all living organisms. Animals cannot synthesize thiamine and depend on their diet. Enhancing the content of thiamine is one of the most important goals of plant breeding to solve the thiamine deficiency associated with the low-thiamin staple crops. In this study, a <italic>Glycine</italic><italic>max</italic><italic>pale</italic><italic>green</italic><italic>leaf 1</italic> (<italic>Gmpgl1</italic>) mutant was isolated from the EMS mutagenized population of soybean cultivar, Williams 82. Map-based cloning of the <italic>GmPGL1</italic> locus revealed a single nucleotide deletion at the 292th nucleotide residue of the first exon of <italic>Glyma.10g251500</italic> gene in <italic>Gmpgl1</italic> mutant plant, encoding a thiamine thiazole synthase. Total thiamine contents decreased in both seedlings and seeds of the <italic>Gmpgl1</italic> mutant. Exogenous application of thiazole restored the pale green leaf phenotype of the mutant. The deficiency of thiamine in <italic>Gmpgl1</italic> mutant led to reduced activities of the pyruvate dehydrogenase (PDH) and pyruvate decarboxylase (PDC), and decreased contents of six amino acids as compared to that in the wild type plants. These results revealed that <italic>GmPGL1</italic> played an essential role in thiamine thiazole biosynthesis.</p>