Pyruvate transporter BnaBASS2 impacts seed oil accumulation in Brassica napus

Abstract

Bile acid: sodium symporter family protein 2 (BASS2) is a sodium-dependent pyruvate transporter, which transports pyruvate from cytosol into plastid in plants. In this study, we investigated the function of chloroplast envelope membrane-localized BnaBASS2 in seed metabolism and seed oil accumulation of Brassica napus (B. napus). Four BASS2 genes were identified in the genome of B. napus. BnaA05.BASS2 was overexpressed while BnaA05.BASS2 and BnaC04.BASS2-1 were mutated by CRISPR in B. napus. Metabolite analysis revealed that the manipulation of BnaBASS2 caused significant changes in glycolysis-, fatty acid synthesis-, and energy-related metabolites in the chloroplasts of 31 day-afterflowering (DAF) seeds. The analysis of fatty acids and lipids in developing seeds showed that BnaBASS2 could affect lipid metabolism and oil accumulation in developing seeds. Moreover, the overexpression (OE) of BnaA05.BASS2 could promote the expression level of multiple genes involved in the synthesis of oil and the formation of oil body during seed development. Disruption of BnaA05.BASS2 and BnaC04.BASS2-1 resulted in decreasing the seed oil content (SOC) by 2.8%-5.0%, while OE of BnaA05.BASS2 significantly promoted the SOC by 1.4%-3.4%. Together, our results suggest that BnaBASS2 is a potential target gene for breeding B. napus with high SOC.

Combined analysis of the metabolome and transcriptome provides insight into seed oil accumulation in soybean

“…In the parallel transcriptomic analysis, glycolytic pathway genes were significantly upregulated, including the GAPDH , PK , and BASS genes. It is reported that Bass2 can increase the oil content of Brassica napus [ 33 ]. Some researchers have revealed that GAPCs can regulate the accumulation of seed oil content [ 34 ].…”

“…Previous studies exhibited that glycolysis metabolites are closely related to seed oil content, such as fructose-6-phosphate (F6P), glucose-6-phosphate (G6P) and fructose-1,6-diphosphate (FBP), etc. [ 33 ]. In the TMHO vs. TMLO and MHO vs. MLO comparison groups, we also found that glycolysis metabolites were enriched.…”

“…A total of 212 subnetworks were identified in the FMHO vs. FMLO comparison group. Multiple studies have demonstrated that genes and metabolites related to the glycolysis pathway affect the accumulation of plant oil [ 33 , 35 ]. Glycolysis is core to the synthesis of oil, as it converts sugars into precursors for the synthesis of fatty acids [ 35 ].…”

Combined analysis of the metabolome and transcriptome provides insight into seed oil accumulation in soybean

“…In the parallel transcriptomic analysis, glycolytic pathway genes were signi cantly unregulated, including the GAPDH, PK, and BASS genes. It is reported that Bass2 can increase the oil content of Brassica napus [35]. Some researchers have revealed that GAPCs can regulate the accumulation of seed oil content [36].…”

“…A total of 212 subnetworks were identi ed in the FMHO vs. FMLO comparison group. Multiple studies have demonstrated that genes and metabolites related to the glycolysis pathway affect the accumulation of plant oil [35,41]. Glycolysis is core to the synthesis of oil, as it converts sugars into precursors for the synthesis of fatty acids [41].…”