Comparative Transcriptome Analysis Reveals Mechanisms of Folate Accumulation in Maize Grains

Abstract

Previously, the complexity of folate accumulation in the early stages of maize kernel development has been reported, but the mechanisms of folate accumulation are unclear. Two maize inbred lines, DAN3130 and JI63, with different patterns of folate accumulation and different total folate contents in mature kernels were used to investigate the transcriptional regulation of folate metabolism during late stages of kernel formation by comparative transcriptome analysis. The folate accumulation during DAP 24 to mature kernels could be controlled by circumjacent pathways of folate biosynthesis, such as pyruvate metabolism, glutamate metabolism, and serine/glycine metabolism. In addition, the folate variation between these two inbred lines was related to those genes among folate metabolism, such as genes in the pteridine branch, para-aminobenzoate branch, serine/tetrahydrofolate (THF)/5-methyltetrahydrofolate cycle, and the conversion of THF monoglutamate to THF polyglutamate. The findings provided insight into folate accumulation mechanisms during maize kernel formation to promote folate biofortification.

Effect of Amino Acids on Folates Accumulation in Wheat Seedlings during Germination under Red Light Radiation

“… Schematic representation of the folate biosynthesis pathway in plants. Chemical compounds: ADC: Aminodeoxychorismate; DHF: Dihydrofolate; DHM: Dihydromyricetin; DHN: Dihydroneopterin; DHP: Dihydropteroate; Glu: Glutamine; GTP: Guanosine−5′-triphosphate; HMDHP: 6-Hydroxymethyldihydropterin; -P/-PP/-PPP: mono/di/triphosphate; ρ -ABA: Para-aminobenzoate; THF: Tetrahydrofolate; THF-Glu n : Tetrahydrofolate polyglutamate; Enzymes: ADCL: aminodeoxychorismate lyase; ADCS: aminodeoxychorismate synthase; DHFS: Dihydrofolate synthase; DHFR: Dihydrofolate synthase reductase; DHNA: Dihydroneopterin aldolase FPGS: Folylpolyglutamate synthetase; GCH1: GTP cyclohydrolase I; HPPK/DHPS: Pyrophosphokinase/dihydropteroate synthase [ 16 ]. …”

Transcriptome Analysis Reveals the Mechanisms of Accumulation and Conversion of Folate Derivatives during Germination of Quinoa (Chenopodium quinoa Willd.) Seeds

“…A similar negative feedback inhibition was found during the development of the maize kernel. Two genes involved in the pterin branch, GCHI and DHNA , were subjected to negative feedback inhibition by 5-CH 3 -THF content . Therefore, it could be hypothesized that the one carbon pool by the folate pathway appropriately controlled the de novo biosynthesis of folate through the regulative synthesis of pterin during quinoa seed germination.…”

“…Two genes involved in the pterin branch, GCHI and DHNA, were subjected to negative feedback inhibition by 5-CH 3 -THF content. 38 Therefore, it could be hypothesized that the one carbon pool by the folate pathway appropriately controlled the de novo biosynthesis of folate through the regulative synthesis of pterin during quinoa seed germination. Moreover, Storozhenko et al found that the coexpression of genes GCHI and ADCS in rice significantly increased the p-ABA level to 38.3 nmol/g, whereas the pterin level was only 0.23 nmol/g.…”

Identification of SbWRKY Transcription Factors in Scutellaria baicalensis Georgi under Drought Stress and Their Relationship with Baicalin

“…Transcriptomics, as a discipline that studies gene function and gene expression at a holistic level and explains the molecular mechanisms of specific biological processes, is an important element of functional genomic research [13,14]. So far, there have been more transcriptomics studies on plants, mainly focusing on economic crops and model crops, such as Oryza sativa L. [15], Zea mays L. [16], Hordeum vulgare L. [17], and Arabidopsis thaliana [18], and relatively few transcriptomics studies on medicinal plants to investigate the effects of abiotic stress on the content of secondary metabolites in medicinal plants. Secondary metabolites are the main components of medicinal plants that exert clinical effects, and the content of secondary metabolites is related to the quality of the medicinal plants [19].…”