Structural and Functional Features of Melatonin Biosynthesis Genes SNAT1 and SNAT2 in Tomato and Garlic Plants

A comparative structural-phylogenetic and expression analysis of the SNAT1 and SNAT2 genes of tomato Solanum lycopersicum and garlic Allium sativum was performed. It was shown that the SNAT1 and SNAT2 are intron-rich and intronless genes, respectively, and may have different evolutionary origins. It was predicted that, unlike the chloroplast protein SNAT1, SNAT2 has features of chloroplast-mitochondrial localization. The highest expression level of SNAT1 and SNAT2 was detected (in silico and qRT-PCR) in leaves, while in roots and mature storage organs it was significantly lower; SNAT2 was not expressed in garlic roots and bulbs. It was found that the expression level of SNAT2 in tomato plant organs is higher than the expression level of SNAT1, while for garlic the opposite ratio was observed.