Limits...
Investigation of the multifunctional gene AOP3 expands the regulatory network fine-tuning glucosinolate production in Arabidopsis.

Jensen LM, Kliebenstein DJ, Burow M - Front Plant Sci (2015)

Bottom Line: In this study, we use transgenic plants in combination with natural variation to investigate the regulatory role of the AOP3 gene found in GS-AOP locus previously suggested to contribute to the regulation of glucosinolate defense compounds.Phenotypic analysis and QTL mapping in F2 populations with different AOP3 transgenes support that the enzymatic function and the AOP3 RNA both play a significant role in controlling glucosinolate accumulation.Furthermore, we find different loci interacting with either the enzymatic activity or the RNA of AOP3 and thereby extend the regulatory network controlling glucosinolate accumulation.

View Article: PubMed Central - PubMed

Affiliation: DNRF Center DynaMo, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen Frederiksberg, Denmark ; Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen Frederiksberg, Denmark.

ABSTRACT
Quantitative trait loci (QTL) mapping studies enable identification of loci that are part of regulatory networks controlling various phenotypes. Detailed investigations of genes within these loci are required to ultimately understand the function of individual genes and how they interact with other players in the network. In this study, we use transgenic plants in combination with natural variation to investigate the regulatory role of the AOP3 gene found in GS-AOP locus previously suggested to contribute to the regulation of glucosinolate defense compounds. Phenotypic analysis and QTL mapping in F2 populations with different AOP3 transgenes support that the enzymatic function and the AOP3 RNA both play a significant role in controlling glucosinolate accumulation. Furthermore, we find different loci interacting with either the enzymatic activity or the RNA of AOP3 and thereby extend the regulatory network controlling glucosinolate accumulation.

No MeSH data available.


The enzymatic activity of AOP3 causes a shift in the production of C3–C4 glucosinolates. The distribution of plants for different C3/(C3 + C4) ratios in the four different AOP3 populations. Red = AOP3 FL6 population, green = AOP3 FL9 population, purple = AOP3 UT2 population, and blue = AOP3 UT10 population.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4585220&req=5

Figure 4: The enzymatic activity of AOP3 causes a shift in the production of C3–C4 glucosinolates. The distribution of plants for different C3/(C3 + C4) ratios in the four different AOP3 populations. Red = AOP3 FL6 population, green = AOP3 FL9 population, purple = AOP3 UT2 population, and blue = AOP3 UT10 population.

Mentions: We analyzed the glucosinolate content of 200–300 plants from each F2 population segregating from the four different parents and the expression of AOP3 in the offspring F3 population (Figure S1, Tables S5–S8). Glucosinolate analysis revealed that in contrast to the FL6 population, none of the plants in the FL9 population contained the product of the AOP3 enzyme, 3ohp, although both the FL6 and FL9 population segregated with the construct encoding the active AOP3 enzyme and expression of the transcript (Figure S1). The absence of 3ohp product shows that the FL9 construct has been functionally silenced by an unknown mechanism. Thus, the FL6 and FL9 population contain the same construct, however, the functional silencing lead to different phenotypic consequences. A survey of the ratio of C3/(C3 + C4) showed that the FL6 population had a shifted ratio in comparison to the FL9 population. Plants with ratios between 0.5 and 0.9 [50–90% C3/(C3 + C4)] were seen to a large extent in the FL6 population containing the enzymatically active AOP3. In contrast, no plants with these ratios were found in the FL9, UT2, and UT10 populations (Figure 4). The plants with high C3/(C3 + C4) ratios from the FL6 population had on average higher levels of 3ohp than the plants with lower relative amounts of C3. Thus, a high level of conversion of 3msp to 3ohp by the active AOP3 mediates a shift from C4 to C3 glucosinolate production showing that the enzymatic activity contributes to regulation of glucosinolate profiles. However, this capacity may depend on other genetic loci specific to Gie-0, as no plants in the Col-0 × Ler-0 population displayed this unusual C3/(C3 + C4) ratio.


Investigation of the multifunctional gene AOP3 expands the regulatory network fine-tuning glucosinolate production in Arabidopsis.

Jensen LM, Kliebenstein DJ, Burow M - Front Plant Sci (2015)

The enzymatic activity of AOP3 causes a shift in the production of C3–C4 glucosinolates. The distribution of plants for different C3/(C3 + C4) ratios in the four different AOP3 populations. Red = AOP3 FL6 population, green = AOP3 FL9 population, purple = AOP3 UT2 population, and blue = AOP3 UT10 population.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4585220&req=5

Figure 4: The enzymatic activity of AOP3 causes a shift in the production of C3–C4 glucosinolates. The distribution of plants for different C3/(C3 + C4) ratios in the four different AOP3 populations. Red = AOP3 FL6 population, green = AOP3 FL9 population, purple = AOP3 UT2 population, and blue = AOP3 UT10 population.
Mentions: We analyzed the glucosinolate content of 200–300 plants from each F2 population segregating from the four different parents and the expression of AOP3 in the offspring F3 population (Figure S1, Tables S5–S8). Glucosinolate analysis revealed that in contrast to the FL6 population, none of the plants in the FL9 population contained the product of the AOP3 enzyme, 3ohp, although both the FL6 and FL9 population segregated with the construct encoding the active AOP3 enzyme and expression of the transcript (Figure S1). The absence of 3ohp product shows that the FL9 construct has been functionally silenced by an unknown mechanism. Thus, the FL6 and FL9 population contain the same construct, however, the functional silencing lead to different phenotypic consequences. A survey of the ratio of C3/(C3 + C4) showed that the FL6 population had a shifted ratio in comparison to the FL9 population. Plants with ratios between 0.5 and 0.9 [50–90% C3/(C3 + C4)] were seen to a large extent in the FL6 population containing the enzymatically active AOP3. In contrast, no plants with these ratios were found in the FL9, UT2, and UT10 populations (Figure 4). The plants with high C3/(C3 + C4) ratios from the FL6 population had on average higher levels of 3ohp than the plants with lower relative amounts of C3. Thus, a high level of conversion of 3msp to 3ohp by the active AOP3 mediates a shift from C4 to C3 glucosinolate production showing that the enzymatic activity contributes to regulation of glucosinolate profiles. However, this capacity may depend on other genetic loci specific to Gie-0, as no plants in the Col-0 × Ler-0 population displayed this unusual C3/(C3 + C4) ratio.

Bottom Line: In this study, we use transgenic plants in combination with natural variation to investigate the regulatory role of the AOP3 gene found in GS-AOP locus previously suggested to contribute to the regulation of glucosinolate defense compounds.Phenotypic analysis and QTL mapping in F2 populations with different AOP3 transgenes support that the enzymatic function and the AOP3 RNA both play a significant role in controlling glucosinolate accumulation.Furthermore, we find different loci interacting with either the enzymatic activity or the RNA of AOP3 and thereby extend the regulatory network controlling glucosinolate accumulation.

View Article: PubMed Central - PubMed

Affiliation: DNRF Center DynaMo, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen Frederiksberg, Denmark ; Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen Frederiksberg, Denmark.

ABSTRACT
Quantitative trait loci (QTL) mapping studies enable identification of loci that are part of regulatory networks controlling various phenotypes. Detailed investigations of genes within these loci are required to ultimately understand the function of individual genes and how they interact with other players in the network. In this study, we use transgenic plants in combination with natural variation to investigate the regulatory role of the AOP3 gene found in GS-AOP locus previously suggested to contribute to the regulation of glucosinolate defense compounds. Phenotypic analysis and QTL mapping in F2 populations with different AOP3 transgenes support that the enzymatic function and the AOP3 RNA both play a significant role in controlling glucosinolate accumulation. Furthermore, we find different loci interacting with either the enzymatic activity or the RNA of AOP3 and thereby extend the regulatory network controlling glucosinolate accumulation.

No MeSH data available.