Expression Profiling of Sucrose Metabolizing Genes in Saccharum, Sorghum and Their Hybrids

Abstract

Sucrose phosphate synthase (SPS; EC 2.4.1.14), sucrose synthase (SuSy; EC 2.4.1.13) and soluble acid invertase (SAI; EC 3.2.1.26) are key enzymes that regulate sucrose fluxes in sink tissues for sucrose accumulation in sugarcane and sorghum. In this study, the expression profiling of sucrose-related genes, i.e. SPS, SuSy and SAI in two sets of hybrids viz., one from a Sorghum × Saccharum cross and the other from a Saccharum × Sorghum cross, high- and low-sucrose varieties, sweet and grain sorghum lines was carried out using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) at monthly intervals. The results indicated differential expression of the three genes in high- and low-sucrose forms. Expression of SPS and SuSy genes was high in high-sucrose varieties, Saccharum × Sorghum hybrids and sweet sorghum and lower in low-sucrose varieties, Sorghum × Saccharum hybrids and grain sorghum. SAI showed a lower expression in high-sucrose varieties, Saccharum × Sorghum hybrids and sweet sorghum and higher expression in low-sucrose varieties, Sorghum × Saccharum hybrids and the grain sorghum. This study describes the positive association of SPS and SuSy and negative association of SAI on sucrose accumulation. This is the first report of differential expression profiling of SPS, SuSy and SAI in intergeneric hybrids involving sugarcane and sorghum, which opens the possibility for production of novel hybrids with improved sucrose content and with early maturity.

Selection of reliable reference genes for RT-qPCR analysis during developmental stages and abiotic stress in Setaria viridis

“…SuSy expression is known to increase during the plant life cycle in C4 species such as sugarcane and sorghum373839. The increase of SuSy expression levels during the late stages of S. viridis development was confirmed using EXP / KIN , the best pair of reference genes for the developmental stages dataset (Fig.…”

“…Similarly, top ranked reference genes samples for developmental stages datasets were validated using SuSy gene, responsible for sucrose synthase production and involved in the sucrose metabolism in plants. SuSy expression is known to increase during the plant life cycle in C4 species such as sugarcane and sorghum 37 38 39 . The increase of SuSy expression levels during the late stages of S. viridis development was confirmed using EXP / KIN , the best pair of reference genes for the developmental stages dataset ( Fig.…”