Sucrose transporter2 contributes to maize growth, development, and crop yield

Abstract

During daylight, plants produce excess photosynthates, including sucrose, which is temporarily stored in the vacuole. At night, plants remobilize sucrose to sustain metabolism and growth. Based on homology to other sucrose transporter (SUT) proteins, we hypothesized the maize (Zea mays) SUCROSE TRANSPORTER2 (ZmSUT2) protein functions as a sucrose/H þ symporter on the vacuolar membrane to export transiently stored sucrose.To understand the biological role of ZmSut2, we examined its spatial and temporal gene expression, determined the protein subcellular localization, and characterized loss-offunction mutations. ZmSut2 mRNA was ubiquitously expressed and exhibited diurnal cycling in transcript abundance. Expressing a translational fusion of ZmSUT2 fused to a red fluorescent protein in maize mesophyll cell protoplasts revealed that the protein localized to the tonoplast. Under field conditions, zmsut2 mutant plants grew slower, possessed smaller tassels and ears, and produced fewer kernels when compared to wild-type siblings. zmsut2 mutants also accumulated two-fold more sucrose, glucose, and fructose as well as starch in source leaves compared to wild type. These findings suggest (i) ZmSUT2 functions to remobilize sucrose out of the vacuole for subsequent use in growing tissues; and (ii) its function provides an important contribution to maize development and agronomic yield.

Transcriptome and metabolome reveal distinct carbon allocation patterns during internode sugar accumulation in different sorghum genotypes

“…Three gene families encoding sucrose transporters have been implicated in sugar accumulation in sorghum, including H + /sucrose antiporters located on tonoplast TSTs (Bihmidine et al ., ), H + /sucrose symporters SUTs (Bihmidine et al ., ; Leach et al ., ; Milne et al ., ), and the clade III of SWEET (Eom et al ., ; Mizuno et al ., ). We compared expression patterns of these gene families between the three genotypes (Figure S20).…”

Transcriptome and metabolome reveal redirection of flavonoids in a white testa peanut mutant

“…Sugars supply plants with energy and functioned in flavonoids accumulation [26,27]. Three gene families encoding sucrose transporters have been implicated in plant sugar accumulation, including TSTs [28], SUTs [29][30][31], and clade III of SWEET [32][33][34]. We compared the expression patterns of these gene families between wsc and WT (Additional file 12) and found seven SUTs to occur at significantly higher levels within wsc than WT even though expression patterns were different; Aradu.M7BX0, Aradu.QA3D9, and Aradu.SQ8X7 were all owned highest levels at the early developmental stage and adjusted to a moderate level; in contrast, Araip.53MMF exhibited a higher expression level within wsc at DAF60 while the other three SUTs were characterized by consistently higher expression levels in mutants at the all three stages (Additional file 12).…”

Interaction between induced and natural variation atoil yellow1delays reproductive maturity in maize

“…Leaf samples were ground into a fine powder and ~100 275 mg of the powder was used to extract sucrose, glucose, fructose, and starch using a previously 276 described method (Leach and Braun 2016). The quantification of these NSC was done using a 277 previously described method (Leach et al 2017). Briefly, high-performance anion exchange 278 (HPAE) chromatography (ICS-5000, Thermo-Fisher Scientific) was used to analyze the neutral 279 fraction of the extract.…”